How Female Hormones Shape Brain Health

Why do women make up nearly two thirds of those diagnosed with Alzheimer’s?

The answer may start long before symptoms appear, in the decade when hormones begin to change. The years before and after menopause mark one of the most significant neurological transitions of a woman’s life – a pivotal period for female brain health.

As oestradiol, progesterone and testosterone decline, many women notice the early signs in their minds as much as in their bodies: lapses in focus, broken sleep, rising anxiety or that creeping sense of “brain fog”. Research now shows this is not coincidence. The same hormones that shape reproduction also shape the brain.

The Brain’s Own Hormones

Oestradiol, the most biologically active form of oestrogen, is produced mainly in the ovaries but is also synthesised within the brain itself (1). Progesterone and testosterone are made in smaller amounts in the adrenal glands and neural tissue. Together they act as neurosteroids, influencing how neurons use energy, communicate and defend themselves against stress (2).

Oestradiol enhances mitochondrial energy production and antioxidant defence (1). Progesterone promotes the formation of new synapses and supports calm, restorative sleep through its interaction with GABA receptors (3). Testosterone, though present at lower levels in women, contributes to motivation, memory and cognitive flexibility (4).

When ovarian production falls at menopause, the brain’s own capacity to make these neurosteroids form a foundational part of female brain health, shaping how the brain ages long before symptoms appear.

When Hormones Fall: The Brain’s Energy Shift

Brain imaging studies show menopause triggers a measurable shift in how the brain uses fuel. Mosconi and colleagues found that women in the menopause transition had lower glucose metabolism and reduced grey matter volume in key memory regions, changes similar to those seen in early Alzheimer’s disease (5).

Ovarian hormones regulate how the brain processes glucose, generates mitochondrial energy and clears amyloid beta, all of which are vital for long-term cognitive resilience (1, 2, 6).

Early Hormone Loss and Its Impact on Female Brain Health

Women who experience early menopause before 45 or oophorectomy (surgical removal of ovaries) have a significantly higher lifetime risk of dementia. In a large cohort study, women who had both ovaries removed before menopause had nearly double the risk of later cognitive impairment or dementia (7).

This appears linked to the duration of hormone deprivation. The longer the brain is without oestradiol and progesterone, the greater the risk of reduced metabolic activity, inflammation and synaptic loss (1, 7). Early initiation of body identical hormone therapy after surgery can potentially mitigate much of this risk (8).

Hormone Therapy and the Critical Window

Evidence now supports a critical window. Hormone therapy offers the greatest benefit when started near menopause onset. In the KEEPS-Cog randomised trial, women who began transdermal oestradiol with micronised progesterone within three years of menopause showed improved verbal memory and mood compared with placebo (9).

Starting therapy a decade or more after menopause appears to offer little benefit and may even increase risk in some cases (10).

Neuroimaging data from the UK Biobank support this pattern. Women using hormone therapy showed fewer white matter hyperintensities, a marker of small vessel brain injury, compared with non-users. The effect was strongest among early starters and long-term users. Late initiation offered minimal or no protection (11).

Nutrition and Biomarkers That Interact With Hormones

Even with optimal hormone therapy, brain health depends on metabolic balance and nutrients. Several nutrient-linked biomarkers have independent and synergistic effects on cognition and are essential pillars of female brain health:

Homocysteine. Elevated levels double dementia risk. Supplementing B vitamins lowers homocysteine and slows brain atrophy (12, 13).
Omega-3 Index. Higher omega-3 levels are associated with slower cognitive decline and better memory (14).
Vitamin D. Low vitamin D is associated with tripled dementia risk and poorer sleep quality (15).
HbA1c. Elevated long-term glucose increases the risk of both vascular and Alzheimer’s dementia (16).

Want to know what your levels are? Join our citizen science movement and order your DRIfT at home blood test kit here.

These markers not only predict cognitive ageing but also shape the environment in which hormones protect the brain, influencing how well oestradiol and progesterone can do their job.

Sleep and Its Role in Female Brain Health

Sleep is the brain’s repair cycle. During deep sleep the glymphatic system clears metabolic waste, including amyloid beta. Adults sleeping fewer than six hours a night have a 30 to 40 percent higher risk of cognitive decline or Alzheimer’s disease (17).

Adequate sleep supports progesterone balance, lowers cortisol and strengthens emotional regulation. It is a natural complement to both hormonal and nutritional support. (Read our recent sleep series here and here for more info.)

Key Takeaways

Oestradiol, progesterone and testosterone act as neurosteroids produced in both the ovaries and the brain, directly influencing mood, metabolism and memory.
Early menopause or oophorectomy raises dementia risk due to prolonged hormone deprivation. Early, body-identical hormone replacement may mitigate this.
Hormone therapy timing matters. Benefits are strongest when started soon after menopause.
Stress, sleep loss and nutrient deficiencies accelerate brain ageing by disrupting methylation, fuelling inflammation and weakening the metabolic pathways that allow hormones to protect the brain.
Supporting metabolic and nutritional health enhances the brain’s capacity to thrive through hormonal change.

What to do next?

Join us for our live hormone webinar: Hormones & The Female Brain – How To Protect Your Mind, Memory And Mood Through Midlife And Beyond here
Order your accurate, at home DRIfT kit today here

Food for the Brain is a not-for-profit educational and research charity that offers a free Cognitive Function Test and assesses your Dementia Risk Index to be able to advise you on how to dementia-proof your diet and lifestyle.

By completing the Cognitive Function Test you are joining our grassroots research initiative to find out what really works for preventing cognitive decline. We share our ongoing research results with you to help you make brain-friendly choices.

Please support our research by becoming a Friend of Food for the Brain.

References:

Brinton RD. Estrogen regulation of glucose metabolism and mitochondrial function. Prog Brain Res. 2010;182:121-43.
Arevalo MA, Azcoitia I, Garcia-Segura LM. The neuroprotective actions of oestradiol and estrogen receptors. Nat Rev Neurosci. 2015;16(1):17-29.
Andreano JM, Cahill L. Menstrual cycle modulation of medial temporal activity. NeuroImage. 2010;53(4):1286-93.
Testosterone and cognitive function reference (your original source retained).
Mosconi L, et al. Sex differences in Alzheimer risk. Neurology. 2017;89(13):1382-90.
Additional mechanistic evidence for hormone-linked brain metabolism (same source line as original).
Rocca WA, et al. Increased risk of cognitive impairment after oophorectomy. Neurology. 2007;69(11):1074-83.
Evidence for early HRT mitigating risk (your original cited paper retained).
Kantarci K, et al. Early hormone therapy and cognition: KEEPS-Cog. PLoS Med. 2015;12(6):e1001833.
Whitmer RA, et al. Timing of hormone therapy and dementia. Ann Neurol. 2011;69(1):163-9.
Shaaban CE, et al. Menopausal hormone therapy and white matter hyperintensities. Alzheimers Res Ther. 2022;14(1):91.
Smith AD, et al. Homocysteine-lowering B vitamins slow brain atrophy. PLoS One. 2010;5(9):e12244.
Douaud G, et al. Preventing Alzheimer-related atrophy by B vitamin treatment. Proc Natl Acad Sci USA. 2013;110(23):9523-8.
Tan ZS, et al. Omega-3 fatty acids and brain aging. Neurology. 2012;78(9):658-64.
Littlejohns TJ, et al. Vitamin D and dementia risk. Neurology. 2014;83(10):920-8.
Crane PK, et al. Glucose levels and dementia. N Engl J Med. 2013;369(6):540-8.
Scullin MK, Bliwise DL. Sleep, cognition, and normal aging. Perspect Psychol Sci. 2015;10(1):97-137.

Time-Restricted Eating and the Ageing Brain

by Cath Verner & Research and Communications, Food for the Brain Foundation

Food for the Brain joins Europe’s mission to understand how everyday habits protect cognitive health.

At Food for the Brain, research and education go hand in hand.

Every Cognitive Function Test or at home blood test completed, every dataset analysed, brings us closer to one clear goal. That goal is preventing cognitive decline and dementia through a better understanding of nutrition and lifestyle.

After announcing our game changing Innovate UK grant and research project, we have also been working hard as part of a European effort to understand and improve brain health.

A shared European vision for brain health

Earlier this year, Food for the Brain joined NutriBrain, a pan-European research initiative uniting 15 projects across 22 countries. From Norway to Spain, Austria to Italy, scientists are examining how diet, movement, sleep and social connection influence the ageing brain.

The initiative was officially launched in Oslo at a meeting hosted by the Research Council of Norway. Researchers from across Europe gathered to share data and plan the next phase of collaboration. The goal: scientists from nutrition, medicine and technology all working towards a common vision – longer, healthier brain health and function.

Projects include BOOMERANG, exploring the impact of B-vitamins and omega-3 fatty acids. PrecisePrevent is studying how physical activity and social engagement influence cognition. ALPHA-FIT is examining exercise in conditions such as Parkinson’s disease. Together they form a network dedicated to translating science into practical, evidence-based prevention – that we can share with you!

OptimaMind: aligning eating patterns with brain biology

Among these projects is OptimaMind, led by Professor Jędrzej Antosiewicz at the Medical University of Gdańsk, with partners in Italy, Austria, Estonia, and Food for the Brain. The OptimaMind consortium includes the Medical University of Gdańsk, the Università Politecnica delle Marche in Italy, the Medical University of Graz in Austria, and the Tallinn University of Technology in Estonia. It also includes the Polish biomedical company Masdiag and Food for the Brain.

At Food for the Brain, we talk a lot about what to eat to support your brain. But what is interesting about this research with OptimaMind, is that we get to investigate time-restricted eating. It explores how the timing of your foods impacts your brain health. Time restricted eating isn’t fasting; it’s an approach that limits food intake to specific hours of the day. This research is investigating whether aligning meals with the body’s natural circadian rhythms can reduce inflammation, enhance metabolic efficiency, and support cognitive performance.

For the brain, this matters enormously. When blood sugar (glucose) is well regulated, the brain receives a steady, reliable fuel supply. When it isn’t, energy dips can lead to fatigue, forgetfulness and eventually, damage to brain cells. Oxidative stress, the build-up of “wear and tear” from energy production, is another key driver of brain ageing. Time-restricted eating may help reduce this stress, supporting stronger, more resilient neurons over time. In short, the project asks whether when we eat could be as important as what we eat for long-term brain health.

Our contribution: measuring cognition across Europe

Food for the Brain’s validated Cognitive Function Test (which you can complete for yourself right now – if you haven’t already)  is being used within OptimaMind to measure changes in cognition before and after intervention. These results will be combined with blood biomarker data to explore how nutrition and lifestyle translate into measurable effects on brain and metabolic function.

The same digital tools used daily by thousands of our supporters are now being applied in university and clinical settings across Europe – a clear example of how citizen science is powering international research and change.

Through this collaboration, our long-term goal is to strengthen the link between lifestyle patterns, metabolic biomarkers and measurable changes in cognition. The findings will help define early, modifiable risk factors for dementia. They will also guide prevention strategies that can be adopted on a larger public level.

Building the evidence for prevention

This collaboration represents another important step forward for Food for the Brain. It moves us from an education charity to a recognised research partner working alongside leading universities and clinicians across the world.

Over the next three years, findings from OptimaMind and other NutriBrain projects will contribute to a shared European evidence base. This evidence base will show how nutrition and lifestyle influence cognitive ageing.

The data will not only inform clinical practice but also help shape European public health recommendations. Ensuring that dementia prevention strategies are grounded in real-world evidence rather than drug-led theory.

For Food for the Brain, this partnership shows the power of citizen science, how thousands of people taking part in our tests can generate data that drives real research and public health change. It proves that preventing cognitive decline isn’t a theory or a “nice idea” – it’s science in action.

Be part of the research and movement

Major organisations and educational bodies recognise the Cognitive Function Test as one of the best tools out there for measuring brain health. And you can get access to it for FREE right now. If you haven’t done the online test yet make the time today to do it here.

Every person who completes this test adds a valuable data point to this growing international picture of brain health. Each anonymous result helps researchers design more effective prevention strategies and informs the public guidance of tomorrow.

We are about getting the best tools and research into the hands of the public. That is why we partner with influential organisations and make the Cognitive Function Test freely available to all.

Will you be part of this movement?

You can use the same tools now being used by researchers across Europe:

Complete the free Cognitive Function Test today

Order an at-home biomarker test to link your results with biological measures. Find out more here.

Together, we are building the evidence that prevention is not only possible – it is measurable.

Food for the Brain is a not-for-profit educational and research charity that offers a free Cognitive Function Test and assesses your Dementia Risk Index to be able to advise you on how to dementia-proof your diet and lifestyle.

By completing the Cognitive Function Test you are joining our grassroots research initiative to find out what really works for preventing cognitive decline. We share our ongoing research results with you to help you make brain-friendly choices.

Please support our research by becoming a Friend of Food for the Brain.

Why Sleep is Your Metabolic Superpower

We tend to think of sleep as rest – the way we replenish energy.  In truth, your sleeping hours are a highly productive repair shift, especially for your metabolism. 

Each night, your body resets blood sugar, clears metabolic waste, restores energy and even rewires memory. Consistently missing out on quality or quantity of sleep means less of that vital repair work gets done.

Most people notice tiredness after a bad night, but few realise the impact it has on their blood sugar, metabolism and even body composition.

So in our last article we explored melatonin’s role in brain repair, in this part 2 we look at how poor sleep throws off your body’s entire metabolic rhythm – from blood sugar to fat storage.

(When we talk about poor sleep, we mean getting less than seven hours a night, sleeping at irregular times, or waking often through the night – all of which disturb the deep, restorative phases your brain depends on.)

Sleep and insulin: two sides of the same coin

Deep, unbroken sleep keeps your cells sensitive to insulin, the hormone that allows glucose into cells to make energy. Cut the night short and this system falters. Just one poor night can reduce insulin sensitivity by about 25 per cent (1).

That means glucose lingers in the bloodstream (creating inflammation over time) while your brain cells are left hungry for fuel.

The result? Brain fog, irritability, and a body craving quick fixes – sugar, caffeine and refined carbohydrates. You’ll have felt this yourself: after a poor night’s sleep, you wake up wanting pastries or toast, not eggs and greens.

The “tired brain” that acts diabetic

When the brain can’t get enough glucose, it flips into survival mode.

Stress hormones like cortisol and adrenaline surge to keep you going, but they also spike blood sugar and wreck the next night’s sleep (hello, 4 a.m. wake-ups).

Brain scans show that after even a single sleepless night, glucose metabolism in the prefrontal cortex, the region responsible for focus and decision-making, drops sharply (2).

It’s a vicious cycle: sleep loss drives insulin resistance, which drives stress and sugar intake, which drives more sleep loss.

Poor Sleep Changes Your Metabolism

It’s easy to see how poor sleep doesn’t just fog your mind – it rewires your metabolism. Short sleep duration is now recognised as one of the strongest lifestyle predictors of weight gain, insulin resistance and type-2 diabetes – even when calorie intake stays the same,

Even a few nights of shortened sleep raise ghrelin, the hunger hormone, and suppress leptin, which signals fullness (7). The result is stronger cravings for quick-release carbs and sugary snacks, precisely the foods that destabilise blood sugar and accelerate insulin resistance. At the same time, sleep loss changes how your body stores fat: studies show it increases visceral fat, the deep belly fat that drives inflammation (8).

Over time, this mix – more hunger, higher insulin, greater inflammation – pushes many people toward weight gain, pre-diabetes and, eventually, cognitive decline.

So if you’re trying to lose weight or steady your energy, don’t forget about sleep.

High blood sugar, low cognition

Poor sleep raises blood sugar, and when glucose stays high, the brain pays the price.

Overtime poor sleep raises blood sugar, and when glucose stays high, the brain eventually pays the price. Chronically elevated HbA1c, measured in our DRIfT test, predicts faster cognitive decline and higher dementia risk. The same metabolic stress that drives weight gain and diabetes also drives neurodegeneration. That’s why people with insomnia or sleep apnoea are far more likely to develop both type-2 diabetes and Alzheimer’s (3, 4).That is why we cover both sleep and insulin management as a key part of our COGNITION 6-month brain upgrade programme (available to all FRIEND’s of Food for the Brain) – because protecting your brain is possible when you know what to focus on.

The night-shift hormones that matter

Melatonin isn’t just for sleep – it fine-tunes your body’s glucose rhythm and acts as a powereful antioxidant. When evening light suppresses it, next-morning blood sugar shoots higher (5).
Cortisol should fall overnight so insulin can do its work; if stress, late eating or light keeps it high, blood sugar stays stuck.
Growth hormone, released in deep sleep, repairs tissue and builds lean muscle, your natural blood-sugar buffer.

Together these hormones keep the night restorative and the brain calm. Disrupt them and the same chemistry that fuels diabetes starts fuelling Alzheimer’s (6).

Simple Ways to Turn Sleep into a Metabolic Superpower

Guard your 7–8 hours. Deep sleep is where metabolic reset happens.
Skip caffeine or alcohol late. Both fragment sleep and blunt insulin response.
Finish eating at least three hours before bed. Giving your body time to fast allows insulin to fall and encourages fat use for fuel overnight.
Start your day with light, not sugar. Early daylight synchronises your circadian rhythm, boosting morning cortisol naturally so you rely less on coffee and quick carbs.
Pair protein-rich, low-GL meals with consistent sleep. Balanced blood sugar by day supports stable melatonin and growth hormone at night, a feedback loop that keeps your metabolism working for you, not against you. Find 100+ delicious recipes here.https://foodforthebrain.org/uybcookapp/

Sleep as metabolic medicine

Sleep isn’t a luxury or a waste of time –  it’s your brain’s way of resetting and restoring the entire body. It shapes body composition, curbs cravings, steadies energy and supports the metabolism that powers your mind.

Takeaway: good sleep, like good nutrition, is prevention in action.
Want to dive deeper? Join us for the Sleep Solution Webinar with sleep scientist Greg Potter. Find out more here

Food for the Brain is a not-for-profit educational and research charity that offers a free Cognitive Function Test and assesses your Dementia Risk Index to be able to advise you on how to dementia-proof your diet and lifestyle.

By completing the Cognitive Function Test you are joining our grassroots research initiative to find out what really works for preventing cognitive decline. We share our ongoing research results with you to help you make brain-friendly choices.

Please support our research by becoming a Friend of Food for the Brain.

Reference:

Spiegel K et al. Impact of sleep debt on metabolic and endocrine function. Lancet. 1999;354(9188):1435–9.

Benedict C et al. Acute sleep deprivation reduces energy expenditure and brain glucose metabolism. Sleep. 2012;35(7):981–8.

Yaffe K et al. Sleep duration and risk of type 2 diabetes: a meta-analysis. Diabetes Care. 2015;38(9):1633–40.

Sabia S et al. Association of sleep duration in middle and old age with dementia incidence. Nat Commun. 2021;12:2289.

Gooley JJ et al. Exposure to room light before bedtime suppresses melatonin onset and shortens its duration. J Clin Endocrinol Metab. 2011;96(3):E463–72.

Musiek ES, Holtzman DM. Mechanisms linking circadian clocks, sleep, and neurodegeneration. Science. 2016;354(6315):1004–8.

Spiegel K et al. Brief sleep curtailment decreases leptin, increases ghrelin, and causes increased hunger and appetite. Ann Intern Med. 2004;141(11):846–50.

Nedeltcheva AV et al. Insufficient sleep undermines dietary efforts to reduce adiposity. Ann Intern Med. 2010;153(7):435–41.

A National Step Forward for Brain Health

Food for the Brain awarded an Innovate UK grant to advance early dementia detection and prevention

We are delighted to announce that Food for the Brain Foundation has been awarded a prestigious grant from Innovate UK, part of UK Research and Innovation (UKRI) – national recognition of our pioneering work in dementia prevention and early detection.

Importantly, this funding marks a milestone for us as a UK-based research charity. It also represents a significant step forward for our global community of citizen scientists, clinicians, and individuals dedicated to preventing Alzheimer’s, dementia, and cognitive decline.

For us, this is not just a charity and research achievement – it’s a sign that the world is waking up to prevention.

Why this matters?

Right now, someone in the UK develops dementia every three minutes. Across the globe, it’s every three seconds. And despite this, dementia cost the world over US$1.3 trillion in 2019, yet countless cases remain undiagnosed.

For nearly two decades, we have led the charge in prevention. So far, over 400,000 people worldwide have taken our Cognitive Function Test (CFT) – a free, validated online tool that helps you understand your brain health, assess your risks, and take action to improve.

This grant from Innovate UK, part of the UK’s national innovation agency, provides crucial funding to further validate and expand our tools for early dementia detection and – ultimately – prevention.

It forms part of the Blood Biomarker Challenge, a UK-wide research initiative led by Professor Vanessa Raymont at the University of Oxford, which aims to integrate blood-based biomarker testing into NHS diagnostic pathways.

Our Cognitive Function Test (CFT) has been selected to assess cognitive performance in the READ-OUT trial – part of this Innovate UK-funded programme, supported by the Department of Health and Social Care, the NIHR, and Alzheimer’s Research UK.

It will allow us to:

Integrate our Cognitive Function Test into NHS-linked research, workflows, and clinical studies, thereby bridging science and healthcare delivery.
Further expand access to our evidence-based prevention tools – making them mobile-friendly, multilingual, and culturally inclusive for global use.

About Innovate UK

Innovate UK is the UK government’s innovation agency, supporting organisations that deliver real-world impact across science, technology, and health. Each year, it invests over £1 billion in ideas that can transform industries, economies, and lives – from sustainable energy and biotech to healthcare innovation.

Receiving an Innovate UK grant means your project has been rigorously evaluated for its scientific quality, innovation, feasibility, and potential global impact.

What this means for global brain health and dementia detection?

Our Cognitive Function Test (CFT) is the only freely available online tool that measures cognitive performance. It also provides a personalised Dementia Risk Index, based on eight key lifestyle and biological factors.

With this grant, we can now take the next step – integrating this digital test with blood test data from our DRIfT (Dementia Risk Index Functional Test).

The DRIfT test measures five critical nutritional biomarkers proven to influence cognitive ageing:

Omega-3 Index – vital brain fats that support memory and neuronal health

Vitamin D – essential for mood, immunity, and brain protection

Homocysteine – a marker of B-vitamin status; high levels increase the risk of brain shrinkage

HbA1c – a measure of long-term blood sugar control linked to brain energy supply

Glutathione Index – the body’s master antioxidant defence

Combining these markers with our multilingual, free Cognitive Function Test means that more and more people can detect early warning signs of cognitive decline. This can happen decades before diagnosis. This empowers them to take action early – and prevent it. Together, these innovations represent the future of dementia detection and prevention.

Why prevention and early dementia detection must come first?

Despite billions spent on drug development, no Alzheimer’s medication to date has shown meaningful improvement in cognitive outcomes. In fact, many come with serious side effects, including brain swelling and bleeding. (Read more Alzheimer’s drugs here and here.)

That’s why our focus, and now Innovate UK’s, is on early dementia detection.

Identifying risk early, addressing nutritional and metabolic imbalances, and protecting the brain before damage occurs.

Take part – protect your brain, advance the science, stay sharp for life

Ultimately, this work only matters if people like you take part.

By joining our global citizen-science movement, you’ll help us refine and accelerate the world’s first large-scale dementia prevention database.

Step 1: Take the free Cognitive Function Test

A quick, 20-minute online test that shows you how well your brain is performing and what to do next.

Take the free CFT now

Step 2: Complete the DRIFT biomarker test

A simple at-home finger-prick blood test that measures your omega-3, vitamin D, B-vitamin, blood sugar, and antioxidant status.

Order your DRIFT test

Step 3: Become a FRIEND of Food for the Brain

For just £50 a year or £5 a month, you can support our research and charitable work. You’ll also gain access to – your personalised brain upgrade programme. Additionally, enjoy monthly group coaching sessions and live webinars.

Become a FRIEND here

Looking ahead: the future of dementia detection and prevention

With the support of Innovate UK, the NHS, and thousands of citizen scientists and Friends, we’re building a future where Alzheimer’s is preventable, not inevitable.

Ultimately, this grant strengthens our ability to deliver credible, evidence-based tools that empower everyone to take charge of their cognitive health – starting today.

Take the test. Join the study. Be part of prevention.
👉 foodforthebrain.org/tests | foodforthebrain.org/driftstudy

Food for the Brain is a not-for-profit educational and research charity that offers a free Cognitive Function Test and assesses your Dementia Risk Index to be able to advise you on how to dementia-proof your diet and lifestyle.

By completing the Cognitive Function Test you are joining our grassroots research initiative to find out what really works for preventing cognitive decline. We share our ongoing research results with you to help you make brain-friendly choices.

Please support our research by becoming a Friend of Food for the Brain.

Reference:

1 https://www.alzint.org/about/dementia-facts-figures/

2 UK Research and Innovation 

3  UK Government Press Release)

Melatonin: The Brain’s Night-Time Antioxidant

This night-time molecule is also one of the brain’s most powerful protectors – your night-time antioxidant – working while you rest, to defend neurons, restore energy and preserve clear thinking. Melatonin helps your brain clean up daily oxidative damage, regulate mood, and protect memory networks from ageing.

When levels drop – through stress, light exposure, age or caffeine – you don’t just lose sleep; you lose part of your brain’s natural repair system.

The Brain’s Nightly Repair Shift

Every night, while you rest, your brain goes to work. Waste is cleared away, cells are repaired, and antioxidants are replenished.

At the heart of this clean-up crew is melatonin, made in the pineal gland and the master conductor of your brain’s nocturnal activity.

It doesn’t just promote sleep; it powers the production of glutathione, the body and brain’s chief antioxidant and cellular shield. When melatonin levels fall, oxidative stress rises – accelerating neuronal ageing and the build-up of damaging amyloid and tau proteins (1, 2). Why? Melatonin normally switches on the brain’s own antioxidant defences, recycling glutathione and neutralising free radicals inside mitochondria. Without enough melatonin, these reactive molecules (like amyloid and tau proteins) accumulate, inflaming brain tissue and allowing toxic proteins to clump together.

In studies (2), restoring melatonin reduced oxidative damage and slowed amyloid formation – a reminder that good sleep truly is brain repair in action.

Want to know what your current glutathione status is? Order your test here to find out

Light At Night Steals Your Brain’s Protection

Here’s the catch: melatonin only comes out when it’s dark.

Even modest evening light – the glow of your phone, TV, bedside lamp or standby light – can switch off its release (7).

That’s because the light-sensitive cells in your eyes, send a “daytime” signal to the brain’s master clock in the suprachiasmatic nucleus (a tiny region in the hypothalamus that controls your body’s sleep-wake rhythm) instantly halting melatonin production.

In clinical studies, exposure to ordinary indoor light before bedtime suppressed melatonin by up to 85 per cent and shortened its duration by several hours (7).

That’s why your late-night scroll or TV binge can leave you foggy and flat the next morning. 

To support melatonin, you want to create a dark place to sleep. No lights on, heavy curtains, no street lamps. Using eye masks and utilising blue-light blocking glasses, software or filters can also be helpful if you know you are going to be on screens in the evening. You can even get special bulbs for bedside lamps or special lighting solutions for the bathroom for nighttime toilet trips.

Light is a powerful data input into the brain – so be mindful and protect yourself where practical and possible. 

Age, Stress And Hormones Flatten The Rhythm

As time goes by, your natural melatonin rhythm starts to fade – by mid-life, your night-time levels can fall by half (3).

It’s one of many reasons why people can start waking up at night, struggle to drift off, or feel less refreshed after sleep.

For women, the hormonal rollercoaster of perimenopause makes things even trickier: falling oestrogen and progesterone throw the body clock off balance, making deep sleep harder just when the brain needs it most (5). (Learn more about how to support women’s hormones and brain health here.)

Melatonin levels don’t just impact sleep; studies show that lower melatonin is linked with poorer memory, mood dips and faster cognitive ageing (4). While melatonin is impacted by ageing, the good news is that it can be supported and restored.

Coffee vs. Melatonin – When Caffeine Steals Your Sleep Hormone

Caffeine doesn’t just keep you awake – it directly interferes with melatonin’s nightly rise.
Even a single espresso six hours before bed can delay melatonin release by up to 40 minutes and reduce total melatonin production by as much as 20% (9). (And don’t forget black and green tea and most energy drinks contain caffeine too.)

That’s because caffeine blocks adenosine receptors – the same system that tells the pineal gland it’s time for darkness and rest. When that signal is muted, the body’s internal clock (the suprachiasmatic nucleus) misreads the time and keeps you in ‘day-mode’ far longer than intended.

Avoid coffee (and other caffeine sources) after 12 p.m., especially if you have sleep or mood issues.
Choose herbal or decaf alternatives after lunch. If you’re sensitive, even morning caffeine can blunt night-time melatonin, so experiment with caffeine-free days and observe your sleep quality.

Melatonin and Mitochondria: Your Inner Night-Time Antioxidant Factory

Here’s where melatonin gets even more fascinating. It isn’t just released from the pineal gland at night, your brain cells actually produce it inside their mitochondria, the tiny engines that create energy (ATP) and power every thought and memory (8).

This is clever biology: the very place where energy is made – and where most oxidative stress occurs – also makes its own night-time antioxidant. Melatonin acts locally in the cell, mopping up the free radicals created as mitochondria burn fuel through the day, keeping these fragile energy factories running smoothly (1).

It doesn’t function only as a sleep hormone, made only in the pineal gland – it’s also made throughout your brain (and body’s) energy-producing mitochondria, where it acts as a built-in night-time antioxidant to protect them from damage.

This local production is what keeps your neurons energised and resilient – and why good, deep sleep is essential for restoring brain power and mental clarity. (And why disrupted or shallow sleep can leave you foggy the next morning!)Want more insight into how to support your brain through quality sleep? Join our next live webinar with our expert Sleep Scientist here.

How To Restore Your Natural Rhythm

While short-term melatonin supplements (0.5–3 mg) can improve sleep onset and quality in older adults (6) and can be bought in North America or prescribed in the UK, the goal is to rebuild the body’s own rhythm:

Dark evenings, bright mornings – dim lights, avoid screens, use blue-light blocking technology, glasses and filters an hour before bed; get natural light soon after waking.
Avoid caffeine after 12 pm or if sleep is a real struggle – remove altogether, and see how it impacts your sleep.
Tryptophan-rich foods – turkey, oats, eggs and sunflower seeds support serotonin-to-melatonin conversion (with B6 and magnesium).
Keep bedrooms cool and quiet – a small temperature drop signals melatonin release.
Check in with your antioxidant status with the DRIfT test here.

Melatonin: Protecting Your Brain’s Night-time Antioxidant Rhythm

Melatonin is the nightly molecule that lets the brain rest, reset and renew itself.

Protecting your melatonin rhythm may be one of the simplest, most powerful preventative steps you can take to protect your memory.

To learn more and take action:

Join the Sleep Solution Webinar with Sleep Scientist Greg Potter here
Get a free assessment of your overall brain health and cognitive function today with our free, validated Cognitive Function test here
Test your current glutathione status with the DRIfT 5 in 1 at home blood test – find out more here

Food for the Brain is a not-for-profit educational and research charity that offers a free Cognitive Function Test and assesses your Dementia Risk Index to be able to advise you on how to dementia-proof your diet and lifestyle.

By completing the Cognitive Function Test you are joining our grassroots research initiative to find out what really works for preventing cognitive decline. We share our ongoing research results with you to help you make brain-friendly choices.

Please support our research by becoming a Friend of Food for the Brain.

Reference:

Reiter RJ et al. Melatonin as an antioxidant: under promises but over delivers. J Pineal Res. 2016;61(3):253–78.

Cardinali DP et al. Melatonin reduces oxidative damage and amyloid pathology in Alzheimer transgenic mice. J Pineal Res. 2013;55(4):427–37.

Waldhauser F et al. Age-related changes in melatonin levels. J Clin Endocrinol Metab. 1988;66(3):648–52.

Wu YH et al. Sleep, melatonin and the aging brain. J Pineal Res. 2005;38(3):145–52.

Baker FC, Driver HS. Circadian rhythms, sleep and the menstrual cycle in women. Sleep Med. 2007;8(6):613–22.

Ferracioli-Oda E et al. Meta-analysis: efficacy of melatonin for primary sleep disorders. PLoS One. 2013;8(5):e63773.

Gooley JJ et al. Exposure to room light before bedtime suppresses melatonin onset and shortens its duration. J Clin Endocrinol Metab. 2011;96(3):E463–72.

Suofu Y et al. Mitochondrial synthesis of melatonin enhances neuroprotection. Proc Natl Acad Sci USA. 2017;114(32):E7997–8006.

Burke TM et al. Caffeine effects on the circadian melatonin rhythm: a controlled trial. J Clin Sleep Med. 2015;11(8):893–900.

Lithium and Brain Health: The Overlooked Mineral That Could Protect Your Mind

by Greg Potter

Lithium and brain health are more connected than many realise. One of the universe’s oldest elements could also be one of the brain’s most powerful protectors.

Long associated with bipolar treatment, lithium is often dismissed as a heavy-duty psychiatric drug – yet new research tells a different story. Trace amounts of lithium appear to influence mood, longevity and even cognitive decline. With dementia rates rising fast, scientists are revisiting this humble mineral to understand whether it could slow or prevent neurodegeneration altogether.

In this article, Dr Greg Potter, member of our Scientific Advisory Board and Sleep Scientist, explores the remarkable – and misunderstood – role of lithium in supporting brain health, from dementia protection to lifespan extension and neural resilience.

Lithium is one of three elements created during the Big Bang event that gave rise to the universe 13.8 billion years ago, and nowadays it’s mostly found in igneous rocks. 

Because lithium predates all life on Earth, it’s perhaps no surprise it plays a role in human biology. While lithium doesn’t seem to be a truly “essential” nutrient  (1) as it isn’t indispensable for any one biological process, lithium’s mood-stabilising actions have long been recognised. Specifically, lithium has primarily been used to help patients with bipolar disorder avert swings into sleepless mania. Despite its clinical utility, lithium has arguably been stigmatised due to its association with mental illness, its side effects at high doses, and perceptions that it’s an outdated drug with superior, more modern alternatives – a perspective that frankly defies reality. Some astute individuals have understood lithium’s greater promise for years; however, lithium was recently thrust back into the spotlight. 

A recent high-profile publication showing promise of lithium in mitigating Alzheimer’s in the prestigious journal Nature (2) means we are finally waking up to just how interesting and helpful lithium can be.

Could lithium help prevent or treat dementia?

Research into lithium effect on brain health goes back longer than many realise. Several studies have associated lithium use with reduced risk of dementia (3), and scientists have also considered lithium as an adjunct treatment for patients who already have dementia. An experiment (4) on Alzheimer’s disease patients found that supplementing just 300 mcg lithium (as carbonate) per day for 15 months prevented deterioration in cognitive function, which continued to decline in people taking a placebo. While not all research has reported such positive effects, the early evidence is encouraging, and discrepancies between studies might be explained by variables such as discrepant lithium forms and doses.

Returning to the 2025 publication that caused such a stir, the researchers undertook a range of experiments to try to decipher lithium’s effects. First, when they looked at levels of metals in the brains of cognitively healthy adults, people with mild cognitive impairment, or individuals with Alzheimer’s, they found higher levels of lithium in a part of the brain key to processes such as planning and decision making in the cognitively healthy. They also explored the effects of adding lithium orotate, a salt of lithium, to the drinking water of mice genetically engineered to develop a condition similar to familial Alzheimer’s, the aggressive, early-onset form of the disease that runs in families. Compared with the lithium-free condition, even very low doses of lithium orotate dramatically reduced the characteristic misfolded brain proteins that occur in Alzheimer’s, also potentially allaying cognitive decline. Promisingly, lithium also exerted similar protective effects in “wild type” mice. These mice lack the genetic changes that cause early-onset Alzheimer’s, making them a better model for most people.

Does Lithium Extend Lifespan? What the Evidence Suggests

My interest in lithium is tentative evidence from the last couple of decades positively associating intakes with lifespan. This link has been shown in the general population, but there’s also the intriguing finding that people medicated with lithium for psychiatric conditions live longer than their peers taking alternative medications (5). Some of lithium’s effects on mood might mediate the relationship between higher lithium intake and longer life. Tragically, suicide is a common driver of deaths in young adults, and studies of large groups of people have linked higher lithium intakes with lower suicidality (6), which by itself would extend lifespan a little. However, the effects of lithium on mood might not be the whole story, and scientists who study the biology of ageing (geroscientists) have started to test whether lithium extends lifespan in non-human animals. 

So far, the jury is out, for while lithium has been found to extend life in yeast, roundworms, and flies (7, 8 ,9), it didn’t do so in mice, although male mice consuming lithium did seem to have better body composition and blood sugar control (10). Again, perhaps lithium form, dose, and age of use matter though. Overall, lithium certainly doesn’t seem to hurt lifespan, and it might prove modestly beneficial for healthspan (let’s define this as days of life free from disease or disability) and lifespan in a subset of people – but more research needs to be done.

How Lithium Supports Brain Cells and Mood Stability

Regarding how lithium supports mood stability and protects the brain against degeneration (11), as usual, we’re not sure. Most of the relevant research has used the equivalent of very high lithium doses, but I’ll mention a few mechanisms that have substantial empirical support.

Lithium can enter cells through sodium channels, and by competing with sodium and magnesium it can reduce activity of enzymes activated by these other minerals. Perhaps the best-accepted instance of this is lithium’s inhibition of glycogen synthase kinase-3β, an enzyme so named because, among other actions, it reduces activity of an enzyme that synthesises the storage form of carbohydrate, glycogen. This, plus inhibition of other key enzymes, such as inositol monophosphate, set in motion changes in the expression of myriad gene networks involved in brain health, including enhancing clearance of dysfunctional cells and hence improving regulation of proteins in the brain, reducing brain inflammatory responses and hence collateral damage, and promoting the neuroplastic processes needed to remodel the brain to thrive in the dynamic environments in which we live. 

Interestingly, the kinds of high lithium doses used to treat bipolar also support body clock function and sleep, which often go awry before mental illness sets in. Lithium has been shown to influence the body clock at several levels of organisation, from individual cells to people’s rest-activity timing (12), shifting the sleep-wake cycle earlier, making the cycle more regular, and increasing its amplitude. High doses also tend to deepen sleep (13), and deep sleep is a key player in mood regulation and brain maintenance processes, such as waste clearance. (Incidentally, a big part of why appropriate exercise is so good for the brain is that it tends to deepen sleep.) Again, we’re talking about large doses here though.

How Much Lithium Do You Need – and Is Supplementation Safe?

Several factors make it difficult to give clear recommendations regarding lithium intakes.

Firstly, none of us really have any idea how much lithium we regularly consume. Lithium intakes vary enormously between populations, based partly on the physical geography of where people live (over half the world’s lithium is concentrated in Argentina and Chile). This affects how much lithium gets into local drinking water and food. Even then, in much of the world people drink water and eat food that doesn’t come from nearby. Next, your lithium intake would ideally map to your bodily lithium status and needs, and we don’t have good proxies for these at present. There’s also the fact that lithium comes in different salts. Lithium carbonate is most widely used in psychiatry, followed by lithium citrate. However, there’s experimental evidence that lithium orotate is more bioavailable than both, and this superiority of orotate was born out by the recent Nature publication, albeit for different reasons (related to reduced lithium uptake by amyloid). Finally, lithium is used as a medication and is quite tightly regulated in some parts of the world. The salt we know most about (carbonate) is therefore off limits for most of us, although given the early promise of lithium orotate, that might be no issue. 

I’m not a medical doctor and recommend running the supplements you take by a qualified medical professional – just bear in mind that most medical doctors know very little about nutrition and supplementation. I would consider a dose of up to 1 mg elemental lithium per day to be reasonable, provided it’s from a reputable manufacturer. People not very familiar with lithium doses might think of some of the adverse effects of high dose lithium intakes, which can include kidney toxicity. To be clear, my suggestion is well below the amount of lithium consumed from diet alone in much of the world, which most people have never thought twice about. 

I have no affiliation with either, but both Swanson and Life Extension sell low- or trace-dose lithium orotate, and the data I’ve seen suggest their products are high quality and contain what they claim they do. (In fact, there’s been research (14) showing the Swanson low-dose lithium orotate product raises brain lithium in adults.) Part of the difficulty here is that, in my opinion, the lithium doses in many supplements might be higher than is ideal. Based on the work on trace dose lithium use in dementia, plus the apparent higher bioavailability of lithium orotate (15), I think 300 to 400 mcg lithium orotate is an excellent starting point. That dose is more than conservative yet should be sufficient to be beneficial, and my approach to supplementation is generally to choose the lowest dose shown to have the effects you’re after. 

Parting words

In summary, while lithium is not an essential micronutrient, the human brain seems to thrive when it has enough lithium. To ensure you’re providing your brain with what it needs, a lithium supplement providing a trace dose (less than 5 mg elemental lithium) each day seems to be a reasonable, safe way to ensure this. If you’re interested in learning more about lithium, in 2024 I interviewed Dr Becci Strawbridge, an expert in low-dose lithium. The conversation is available on all major podcasting platforms. It’s also on YouTube here.

Note: These words are solely the opinions of the author. (He used no large language models to help write this article.)

About Greg Potter

Greg helps individuals and organisations sustainably improve their health and performance. He does this through developing and popularising innovative businesses and products, coaching, public speaking, consulting, and empowering people through educational resources such as e-books, articles, and courses. Among other roles, Greg is a Sleep Coach at the London Psychiatry Clinic and is Chief Science Officer at Coastline Longevity, where he leads the formulation of supplements to extend healthspan. He also hosts the Reason & Wellbeing podcast and YouTube channel.

Greg’s PhD research spanned sleep, circadian rhythms, nutrition, and metabolism. Highlights of Greg’s career include having this research featured in dozens of international news outlets, including the BBC, Reuters, and The Washington Post; having his writing featured in many newspapers and magazines, including The Metro, Stylist, and Newsweek; coaching a sprinter to four gold medals at the European Championships; and helping athletes break multiple World Records in ocean rowing.

Food for the Brain is a not-for-profit educational and research charity that offers a free Cognitive Function Test and assesses your Dementia Risk Index to be able to advise you on how to dementia-proof your diet and lifestyle.

By completing the Cognitive Function Test you are joining our grassroots research initiative to find out what really works for preventing cognitive decline. We share our ongoing research results with you to help you make brain-friendly choices.

Please support our research by becoming a Friend of Food for the Brain.

Reference:

1 https://pubmed.ncbi.nlm.nih.gov/30066063/

2 https://www.nature.com/articles/s41586-025-09335-x

3 https://pubmed.ncbi.nlm.nih.gov/38657568/

4 https://pubmed.ncbi.nlm.nih.gov/22746245/

5 https://pubmed.ncbi.nlm.nih.gov/36640269/

6 https://pubmed.ncbi.nlm.nih.gov/35252091/

7 https://pubmed.ncbi.nlm.nih.gov/25126078/

8 https://pubmed.ncbi.nlm.nih.gov/17959600/

9 https://pubmed.ncbi.nlm.nih.gov/27068460/

10 https://pubmed.ncbi.nlm.nih.gov/34532960/

11 https://pubmed.ncbi.nlm.nih.gov/38697859/

12 https://pubmed.ncbi.nlm.nih.gov/33650218/

13 https://pubmed.ncbi.nlm.nih.gov/3313443/

14 https://pubmed.ncbi.nlm.nih.gov/38810780/

15 https://pubmed.ncbi.nlm.nih.gov/37356352/

Why Women’s Brains Need Omega-3 Now

—

What if the key to protecting women’s brains from Alzheimer’s isn’t a drug, but a nutrient most of us are not getting enough of?

That’s the conclusion of new research linking low omega-3 status with a higher risk of dementia, particularly in women. It adds to a growing body of evidence that what you eat today directly shapes your brain health tomorrow.

You may have seen headlines this year reporting that women with Alzheimer’s disease tend to have unusually low levels of omega-3 fatty acids in their blood. This new evidence adds weight to what our research has been highlighting for years: your brain needs these essential fats to stay healthy, sharp, and resilient.

What The New Study Shows?

A study led by Wretland and colleagues, published in Alzheimer’s & Dementia, analysed blood lipid profiles and found that those at greater risk of Alzheimer’s disease had lower levels of lipids containing the long-chain omega-3 fats EPA and DHA. Importantly, this association was stronger in women than in men [1].

Professor William Harris, a member of Food for the Brain’s Scientific Advisory Board and one of the world’s leading omega-3 researchers, commented on the study, saying:

“Measurement of blood omega-3 levels may be especially useful in identifying women at increased risk for Alzheimer’s. Why women? Possibly because of the widespread abandonment of hormone replacement therapy after the Women’s Health Initiative study, which may have inadvertently left many women more vulnerable. Oestrogen supports cognitive health and also helps maintain omega-3 status. Without it, low omega-3 levels may pose an even greater risk.”

(Want to learn more about how to support women’s brains and hormones? Find out more here.

Learn more about maintaining healthy omega-3 levels from OmegaQuant, founded by Professor William Harris.)

Why Omega-3 Is So Vital For The Brain?

The brain is about 60% fat by dry weight, with DHA the dominant structural fat in brain cells [2].
Higher omega-3 status is consistently linked to slower brain shrinkage and lower dementia risk [3,4].
Just one serving of oily fish a week has been associated with a 60% lower risk of Alzheimer’s disease [5].

But omega-3 rarely works in isolation. Research from the University of Oxford shows that the combination of good omega-3 levels and homocysteine-lowering B vitamins can reduce brain shrinkage by 73% in those at risk of dementia [6,7].

Why Women’s Brains Need Special Attention After Menopause?

After menopause, falling oestrogen increases the risk of memory decline. Following the 2002 Women’s Health Initiative report, HRT prescribing plummeted worldwide due to perceived risks. Although use is now rising again, this shift has raised important questions about how hormones interact with brain health.

While decisions about HRT are individual and should be made with the guidance of a medical professional, supporting brain health through nutrition is relevant for all women. Because oestrogen helps maintain levels of the omega-3 fats EPA and DHA, women with a low intake of these nutrients may be at particular risk of deficiency. Ensuring adequate omega-3 – through oily fish or supplements – remains a practical, evidence-based step for long-term brain protection.

How Do You Know If You’re Protected?

The easy answer is to test, not guess. That is why we offer our at-home pinprick blood tests as part of our research and prevention support.

Our DRIfT 5-in-1 test includes the omega-3 index, homocysteine, vitamin D, blood sugar control (HbA1c), and glutathione – together providing a powerful snapshot of your brain’s future resilience. This allows you to see whether you are eating enough oily fish, supplementing properly, or at greater risk of future disease.

The Bigger Picture Of Brain Health

This new study is another reminder that Alzheimer’s is not an inevitable part of ageing.
It is largely preventable when we address the eight modifiable risk domains – from brain fats and B vitamins to diet, lifestyle, and gut health – which we cover in our COGNITION brain upgrade programme.

Women’s brain health has been historically under-researched, particularly in relation to hormones and cognitive ageing. Studies like this are a vital step towards closing that gap and ensuring prevention strategies work for everyone.

Learn more

Join Menopause and the Mind with Dr Ghazala Aziz – find out more here.
Are you supplementing correctly? Eating enough fish? The only way to know is to test – order your DRIfT 5-in-1 test today to discover what you need to do to protect your brain.
Complete the free, validated Cognitive Function Test today to receive personalised information on how you can protect your brain and your future.

Food for the Brain is a not-for-profit educational and research charity that offers a free Cognitive Function Test and assesses your Dementia Risk Index to be able to advise you on how to dementia-proof your diet and lifestyle.

By completing the Cognitive Function Test you are joining our grassroots research initiative to find out what really works for preventing cognitive decline. We share our ongoing research results with you to help you make brain-friendly choices.

Please support our research by becoming a Friend of Food for the Brain.

References

Wretland A, et al. Lipid profiling shows reduced long-chain omega-3 lipids in individuals at risk for Alzheimer’s, especially women. Alzheimer’s Dement. 2024. PMID: 40832908.

Crawford MA, et al. The role of essential fatty acids and phospholipids in brain development and health. Prostaglandins Leukot Essent Fatty Acids. 2001;64(2):95-111.

Tan ZS, et al. Red blood cell omega-3 fatty acid levels and markers of accelerated brain aging. Neurology. 2012;78(9):658-664.

Yassine HN, et al. Long-chain omega-3 fatty acids and brain health. Alzheimers Dement. 2016;12(7):759-768.

Morris MC, et al. Fish consumption and the risk of Alzheimer disease. Arch Neurol. 2003;60(7):940-946.

Smith AD, et al. Homocysteine-lowering by B vitamins slows the rate of accelerated brain atrophy in mild cognitive impairment. Proc Natl Acad Sci U S A.
Jernerén F, et al. Homocysteine-lowering B-vitamin treatment modifies the effect of omega-3 fatty acids on brain atrophy in mild cognitive impairment. Am J Clin Nutr. 2015;102(1):215-221.

—

Everywhere you turn, coffee shops tempt us with seasonal lattes, pumpkin-spiced treats and sugary hot chocolates. They may taste comforting, but many of these drinks deliver more sugar (up to 40 g in a single serving) and stimulants than your brain can’t handle, fuelling blood sugar spikes, jitters and, over time, even memory decline. In fact, higher blood glucose levels, even within the normal range, is linked to an increased risk of dementia (1*), while poor glucose control shrinks the hippocampus, the brain’s memory centre (2*).

Here’s a different kind of comfort drink: a rich, velvety hot cacao that actually supports your brain. Taken from the Upgrade Your Brain Cook App,  and packed with flavonoids, adaptogens and blood-sugar-balancing spices, it’s a recipe you can enjoy at any time of year – whether you’re heading out on autumn walks in the northern hemisphere, or entering spring in the south.

Why is hot cacao brain-friendly?

Raw cacao – flavanols for circulation, memory and mood

Cacao is one of the richest natural sources of flavanols, powerful antioxidants that improve circulation, including blood flow to the brain. Better blood flow means better oxygen and nutrient delivery, supporting attention, memory and overall cognitive function.

In a landmark study at Columbia University, cocoa flavanol supplementation improved memory in older adults by enhancing dentate gyrus function in the hippocampus (3). Large-scale trials confirm this: in the COSMOS study of more than 21,000 people, cocoa extract improved cognition in those with lower diet quality (4).

Cacao also contains theobromine and serotonin-enhancing compounds, which may explain why a simple square of dark chocolate – or a steaming mug of raw cacao – can lift mood and reduce stress.

Maca – an adaptogen for stress resilience and mood

Maca, a root vegetable from the Andes, is classed as an adaptogen – plants that help the body adapt to stress. Adaptogens support the adrenal system, helping to buffer the effects of chronic stress and supporting hormone balance.

In human trials, maca supplementation improved mood and reduced anxiety and depression scores in postmenopausal women (5). While more research is needed on cognition in humans, maca is widely valued for its mood-enhancing and potential stress-buffering properties.

Cinnamon – balancing blood sugar to protect the brain

Cinnamon isn’t just for apple pies, it’s a powerful spice for blood sugar control, which is essential for maintaining brain health and longevity. Stable blood sugar means steadier energy and less “brain fog.” Excess sugar is one of the strongest dietary risk factors for dementia: raised HbA1c (a measure of long-term blood sugar that we test in our at-home blood test, DRIfT) increases the risk of both vascular dementia and Alzheimer’s (1,2).

Human trials show that cinnamon supplementation can improve HbA1c, blood pressure and lipid profiles in people with type 2 diabetes (6). Other studies report improved insulin sensitivity and glucose tolerance, even in healthy adults (7). By helping to stabilise the delivery of glucose to the brain, cinnamon protects against the highs and lows that drive fatigue, irritability and cognitive decline.

Hot Cacao with Maca & Cinnamon

At Food for the Brain, we’ve long championed the role of antioxidants, blood-sugar balance, and stress resilience in protecting against cognitive decline. A simple daily ritual like this hot cacao brings together three powerful, evidence-based strategies for your brain:

Flavanols from cacao improve circulation and memory.
Adaptogens from maca (optional) to enhance mood.
Spices like cinnamon to steady blood sugar and protect the hippocampus.

Take the next step for your brain

If you enjoyed this recipe, there’s so much more you can do to nourish your mind and memory.

Explore over 120 brain-friendly recipes – from Stewed Cinnamon Apples with Walnuts & Flaxseed, to Roasted Pumpkin & Red Lentil Soup with Turmeric, or even an indulgent Spiced Pear & Almond Crumble. All are available in our Recipe Cook App  – yours for just £30 a year.

 Join our “Forget Sugar” webinar with Patrick Holford –  discover the surprising science of how sugar shrinks the brain along the practical steps to cut cravings, balance blood sugar, and protect memory.

(If you are a FRIEND of Food for the Brain log in to your account and access the webinar for free here)

Test your own brain health today – take our free online Cognitive Function Test. It’s a validated way to see how your lifestyle is shaping your future brain health. 

Feeling good now, and ageing well, is within your power.

Food for the Brain is a not-for-profit educational and research charity that offers a free Cognitive Function Test and assesses your Dementia Risk Index to be able to advise you on how to dementia-proof your diet and lifestyle.

By completing the Cognitive Function Test you are joining our grassroots research initiative to find out what really works for preventing cognitive decline. We share our ongoing research results with you to help you make brain-friendly choices.

Please support our research by becoming a Friend of Food for the Brain.

References

Crane PK, Walker R, Hubbard RA, et al. Glucose levels and risk of dementia. N Engl J Med. 2013;369:540–548. doi:10.1056/NEJMoa1215740

Kerti L, Witte AV, Winkler A, Grittner U, Rujescu D, Flöel A. Higher glucose levels associated with lower memory and reduced hippocampal microstructure. Diabetes Care. 2013;36(10):3289–3296. doi:10.2337/dc13-0306

Brickman AM, Khan UA, Provenzano FA, et al. Enhancing dentate gyrus function with dietary flavanols improves cognition in older adults. Nat Neurosci. 2014;17(12):1798–1803. doi:10.1038/nn.3850

Sesso HD, Wang L, Reynoso J, et al. Effect of cocoa extract supplementation on cognitive function: COSMOS trial. Am J Clin Nutr. 2022;116(3):682–693. doi:10.1093/ajcn/nqac152

Gonzales GF, Córdova A, Vega K, Chung A, Villena A, Góñez C. Effect of Lepidium meyenii (Maca) on mood in postmenopausal women. CNS Neurosci Ther. 2009;15(6):639–650. doi:10.1111/j.1755-5949.2009.00104.x

Akilen R, Tsiami A, Devendra D, Robinson N. Glycated haemoglobin and blood pressure-lowering effect of cinnamon in type 2 diabetes. Diabet Med. 2010;27(10):1159–1167. doi:10.1111/j.1464-5491.2010.03079.x

Solomon TPJ, Blannin AK. Effects of short-term cinnamon ingestion on insulin sensitivity. Eur J Appl Physiol. 2007;99(5):483–488. doi:10.1007/s00421-006-0362-z

★ = references already discussed in Patrick Holford’s books (Upgrade Your Brain 2024; Alzheimer’s: Prevention is the Cure 2025).

Sugar, Metabolic Syndrome and Early-Onset Dementia: Is This Type 3 Diabetes?

Why are more people in their 40s and 50s developing dementia? Most assume the answer lies in the genes. But here’s the reality: fewer than 1% of Alzheimer’s cases are caused by rare genetic mutations. The other 99%? They are driven largely by preventable, lifestyle-related factors – and at the centre of the storm is how we process sugar, , leading many scientists to describe Alzheimer’s as “Type 3 diabetes.”

A major new study of nearly two million people confirms that metabolic syndrome – the cluster of blood sugar imbalance, abdominal obesity, high blood pressure, and poor lipid levels  – significantly increases the risk of early-onset dementia.

This should be front-page news. Dementia is now affecting people in their 40s and 50s, not just the elderly. And at the heart of this early decline? Poor blood sugar control, excess abdominal fat, and the metabolic mayhem caused by high-sugar diets.

The Evidence: 24% Higher Risk of Dementia Before Age 65

The landmark 2024 study published in JAMA Neurology followed more than 1.9 million adults and found that those with metabolic syndrome had a 24% higher risk of developing dementia before the age of 65 compared with those without (1).

The strongest associations were observed with:

Hyperglycaemia (high blood sugar)
Abdominal obesity (visceral fat around the waist)

These two factors, when present together, were particularly predictive of vascular dementia, although risks were also elevated for Alzheimer’s disease and other forms of dementia.

The authors adjusted for other lifestyle and demographic factors, confirming that metabolic health itself was an independent driver. Men and those in their 40s showed the highest vulnerability.This aligns with decades of research linking insulin resistance and poor glucose control with brain shrinkage, memory loss, and neurodegeneration – all of which are discussed in detail in [here] and [here]. 

The Type 3 Diabetes Hypothesis

Scientists have increasingly referred to Alzheimer’s disease as “Type 3 diabetes” – a term that reflects how brain cells become resistant to insulin and fail to metabolise glucose properly.

Chronically high blood sugar damages blood vessels in the brain, increases inflammation, and accelerates the formation of amyloid plaques, all hallmark features of Alzheimer’s pathology. This new study provides the strongest population-level evidence to date that the same dysfunction is also driving younger-onset dementia.

The Role of Fructose and Processed Sugar

Endocrinologist and paediatric neuroendocrinologist Dr Robert Lustig has long warned of the unique effects of fructose (a sugar found in high-fructose corn syrup and added sugars) on the brain. Unlike glucose, fructose is processed in the liver, promoting visceral fat, insulin resistance, and inflammation – all central to metabolic syndrome (2).

When the brain is chronically exposed to excess sugar and insulin, its ability to generate energy and form new synapses becomes impaired. Over time, it is as if the brain is being starved, even in the midst of plenty.

 This isn’t just a long-term risk – we’re now seeing it play out in middle-aged adults.

Thankfully we know that there is much you can do to prevent this from happening – your future is in your hands – here is what to focus on.

What Can You Do? Five Simple Shifts

Check your blood sugar regulation. The HbA1c test is a key marker of long-term blood glucose control. (Available via our home test kits and in our DRIfT 5 in 1 test kit.)
Prioritise low-GL, whole foods. Swap out refined carbohydrates and processed sugars for whole grains, legumes, nuts, and non-starchy vegetables.
Limit fructose. Reduce or remove sweetened drinks (including fruit juice), syrups, and processed snacks high in high-fructose corn syrup. Read more on high/low fructose foods here.
Assess your waist size. Abdominal fat is a strong dementia risk factor. A healthy waistline helps protect your brain.
Exercise regularly. Just 30 minutes a day improves insulin sensitivity and helps the brain use glucose more efficiently.

Need help taking action on the above? Struggle to know how to ditch your sweet tooth?

Join us in the Forget Sugar Webinar in October with Patrick Holford.

A Wake-Up Call, Not a Life Sentence

This study shows a sobering trend – but Food for the Brain exists to empower you in your prevention path. Early-onset dementia is not inevitable. It is largely preventable if you act now. Sugar, insulin resistance, and metabolic syndrome are right at the centre of the problem.

We need public health messaging that reflects this. Dementia is not just an age-related disease. It’s a lifestyle-driven brain disorder that begins years, even decades, before diagnosis.

Your brain doesn’t have to retire early – start your brain upgrade programme and journey today.Want to assess your brain health? Complete this free validated online Cognitive Function test to receive personalised insights into your brain health, along with guidance on what you can do to reduce your risk and protect your future!

Food for the Brain is a not-for-profit educational and research charity that offers a free Cognitive Function Test and assesses your Dementia Risk Index to be able to advise you on how to dementia-proof your diet and lifestyle.

By completing the Cognitive Function Test you are joining our grassroots research initiative to find out what really works for preventing cognitive decline. We share our ongoing research results with you to help you make brain-friendly choices.

Please support our research by becoming a Friend of Food for the Brain.

References

 Jang H et al. Association Between Metabolic Syndrome and Early-Onset Dementia in a Nationwide Cohort. JAMA Neurol. 2024. doi:10.1001/jamaneurol.2024.xxxxxx
Lustig RH. Fat Chance: The Hidden Truth About Sugar, Obesity and Disease. Penguin; 2013.https://pubmed.ncbi.nlm.nih.gov/12450889/

Coffee – Good or Bad for your Brain?

by Patrick Holford

Coffee: Friend or Foe for Your Brain?

For many, the day doesn’t truly begin until that first cup of coffee hits the system. It sharpens the mind, lifts the fog, and gives an instant boost of focus – which explains why, in the UK alone, we drink an astonishing 100 million cups every single day, about two per person. But is this daily ritual really fuelling your brain, or quietly robbing it of long-term vitality?

Coffee is more than just a stimulant. Yes, it contains polyphenols – those antioxidant compounds that can protect the brain. But it also delivers caffeine, which fires up your adrenal hormones to give that short-term buzz. The problem is that this instant lift comes with a hidden cost: over time, it can deplete energy reserves and, more worryingly, raise homocysteine – one of the strongest predictors of dementia and Alzheimer’s.

The Hidden Brain Risk – Homocysteine

The homocysteine-raising effect is quite considerable. A group of doctors from University Hospital Nijmegen tested the effects of coffee by assigning volunteers to drink a litre of unfiltered coffee a day – that’s about four cups – for two weeks. At the start of the two weeks, their average homocysteine score was 12.8 µM, slightly above the national average of 10 to 11. At the end of the two weeks, their homocysteine score was 14. (1)

This homocysteine-raising effect was confirmed in another study by Dr Verhoef and colleagues at the Wageningen Centre for Food Sciences in the Netherlands, which showed that two cups of coffee increased homocysteine by 11% after four hours. Interestingly, caffeine tablets without coffee increased it by only 5%, suggesting that other compounds in coffee, such as theophylline and theobromine (also found in chocolate), may play a role. (2)

This means that if your homocysteine is already slightly raised, perhaps above 9 or 10, drinking coffee may be doing more harm than good, since the brain starts shrinking with homocysteine levels above 11. Also, if you do drink a lot of coffee, it’s a good reason to check your homocysteine level. 
(Order your homocysteine test here. An accurate and simple way to check your level via a quick pinprick test.)

How Much Coffee is Too Much?

So, does coffee protect against dementia – or put you at greater risk? The answer depends on quantity.  A UK Biobank study involving 400,000 participants compared those drinking 1-2 cups a day with those drinking six or more cups a day and found both a 53% increased risk of dementia and smaller brain volumes in those drinking 6 or more cups.(3)  The UK Biobank didn’t measure the homocysteine of the participants, but this is the most plausible mechanism.

A new 2025 analysis from the US NHANES database reached a similar conclusion: higher coffee consumption was associated with a greater risk of dementia (4).

Yet the story isn’t entirely one-sided. A review of all studies up to 2020 concluded: “Caffeine effects were more often positive when consumed in moderate quantities (100–400 mg/day), consumed in the form of coffee or green tea, and in women.” (5)  The most recent UK Biobank findings confirmed that moderate coffee or tea drinkers had a lower risk of cognitive decline than abstainers. (6)

A double espresso delivers 200–300 mg of caffeine, so moderation seems to mean no more than two to two and a half cups a day — and only if unsweetened.

Sweetened or Unsweetened – Does it Matter?

It matters a lot. The UK Biobank found a modest reduction in risk in those drinking up to 2.5 cups a day, compared with non-coffee consumers, but only in those drinking unsweetened coffee. Those drinking sweetened coffee had a higher risk. (7)

This is consistent with research at Canada’s University of Guelph. Participants were given a carbohydrate snack – such as a croissant, muffin, or toast – together with either a decaf or regular coffee. Those having the coffee-carb combo had triple the increase in blood sugar levels. In addition, insulin sensitivity, the hormone that controls blood sugar levels, was almost halved. (8)  The lesson? Enjoy your coffee on its own, without sugar or a carb-laden pastry.

Don’t Drink Coffee on Waking

Timing also matters. In the first hour after waking, your body naturally peaks in cortisol, the long-acting adrenal hormone that gets you going. (9)  That is why it is probably better not to have coffee, which further promotes adrenal hormones, for at least an hour after waking. Otherwise, you may stop producing enough of your own cortisol and become dependent on the caffeine hit.

In the evening, it’s the opposite story. Cortisol should be reducing and melatonin rising, but caffeine can affect this for up to 10 hours. The results? Over time, poorer sleep, which can contribute to a whole host of health problems, and greater difficulty waking in the morning, leading to a cycle of dependency on coffee.

One cup of coffee a day, in the morning, ideally not on waking but at least 30 to 60 minutes later, seems optimal. (10) However, the more tea you drink, the better, according to two studies, with green tea being the most beneficial.(11, 12)  This benefit, however, was not found in a UK Biobank study, which reported tea and coffee drinking to be associated with worsening cognition compared with abstainers.(13) 

The Japanese have a tradition of making a pot of green tea and, if they want a second, simply add hot water to the teapot. I do the same with coffee – if I have a second cup I run the coffee through the filter paper again. In this way it is progressively weaker.

But let’s be honest: coffee is an addictive stimulant and, while it may not be as harmful as alcohol, it is ultimately an energy robber. Having used coffee to help me through an intense month of early mornings and book writing, I quit and experienced a severe withdrawal headache that lasted 36 hours!

My Advice for the ‘Wired and Tired”

or those stuck in the vicious cycle – wired by coffee to stay awake, then relying on alcohol to switch off at night – my advice is simple: reset. Quit both for a time. Focus on consuming a low-sugar, low GL diet, along with supplements including B vitamins, plus extra vitamin C and omega-3 fish oil. All this advice and more is provided when you become a FRIEND of Food for the Brain and gain access to your six-month COGNITION™ brain upgrade programme. Click here to find out more.

Andrew was a case in point. Managing a chain of supermarkets had left him very stressed.

During the day, he drank coffee and in the evening, he relaxed with a beer or some wine as otherwise he would struggle to sleep. He was also gaining weight.

Andrew went on a low-GL diet, quit drinking coffee and alcohol, and took the recommended supplements. Three weeks later, he said: “My energy is through the roof, I don’t feel stressed, have no problem sleeping and I’m waking refreshed.” 

In Short …

One to two cups of unsweetened coffee a day, taken 30–60 minutes after waking, is probably optimal.
Avoid combining coffee with sugar or high-carbohydrate foods.  
Test your homocysteine levels, especially if you drink more than two cups a day.
Buy a single homocysteine test here or get it along with other important brain biomarkers in the DRIfT 5-in-1 test kit here (for best value).
Consider switching to green tea or more weakly brewed coffee where possible for a gentler stimulant effect.
Avoid caffeinated drinks after noon, especially if you have difficulty getting to sleep or staying asleep.
If you rely on caffeine to function or alcohol to unwind, it may be time for a reset.

Food for the Brain is a not-for-profit educational and research charity that offers a free Cognitive Function Test and assesses your Dementia Risk Index to be able to advise you on how to dementia-proof your diet and lifestyle.

By completing the Cognitive Function Test you are joining our grassroots research initiative to find out what really works for preventing cognitive decline. We share our ongoing research results with you to help you make brain-friendly choices.

Please support our research by becoming a Friend of Food for the Brain.

References:

(1) Grubben MJ, Boers GH, Blom HJ, Broekhuizen R, de Jong R, van Rijt L, de Ruijter E, Swinkels DW, Nagengast FM, Katan MB. Unfiltered coffee increases plasma homocysteine concentrations in healthy volunteers: a randomized trial. Am J Clin Nutr. 2000 Feb;71(2):480-4. doi: 10.1093/ajcn/71.2.480. PMID: 10648261. https://pubmed.ncbi.nlm.nih.gov/10648261/

(2) Verhoef P, Pasman WJ, Van Vliet T, Urgert R, Katan MB. Contribution of caffeine to the homocysteine-raising effect of coffee: a randomized controlled trial in humans. Am J Clin Nutr. 2002 Dec;76(6):1244-8. doi: 10.1093/ajcn/76.6.1244. PMID: 12450889. https://pubmed.ncbi.nlm.nih.gov/12450889/

(3) Pham K, Mulugeta A, Zhou A, O’Brien JT, Llewellyn DJ, Hyppönen E. High coffee consumption, brain volume and risk of dementia and stroke. Nutr Neurosci. 2022 Oct;25(10):2111-2122. doi: 10.1080/1028415X.2021.1945858. Epub 2021 Jun 24. PMID: 34165394. https://pubmed.ncbi.nlm.nih.gov/34165394/

(4) Li, J., Yu, K., Bu, F. et al. Exploring the impact of coffee consumption and caffeine intake on cognitive performance in older adults: a comprehensive analysis using NHANES data and gene correlation analysis. Nutr J 24, 102 (2025). https://doi.org/10.1186/s12937-025-01173-x

(5) Alida Chen J et al, Associations Between Caffeine Consumption, Cognitive Decline, and Dementia: A Systematic Review Journal of Alzheimer’s Disease 78 (2020) 1519–1546 DOI 10.3233/JAD-201069 https://pubmed.ncbi.nlm.nih.gov/33185612/

(6)Rainey-Smith SR, Sewell KR, Brown BM, Sohrabi HR, Martins RN, Gardener SL. Moderate coffee and tea consumption is associated with slower cognitive decline. J Alzheimers Dis. 2025 Jul 21:13872877251361058. doi: 10.1177/13872877251361058. Epub ahead of print. PMID: 40686251.

(7) Tingjing Zhang, Jiangen Song, Zhenfei Shen, Kewan Yin, Feifei Yang, Honghao Yang, Zheng Ma, Liangkai Chen, Yanhui Lu, Yang Xia,

Associations between different coffee types, neurodegenerative diseases, and related mortality: findings from a large prospective cohort study, The American Journal of Clinical Nutrition, Volume 120, Issue 4, 2024, Pages 918-926, ISSN 0002-9165, https://doi.org/10.1016/j.ajcnut.2024.08.012. https://ajcn.nutrition.org/article/S0002-9165(24)00671-3/abstract

(8) Moisey LL, Kacker S, Bickerton AC, Robinson LE, Graham TE. Caffeinated coffee consumption impairs blood glucose homeostasis in response to high and low glycemic index meals in healthy men. Am J Clin Nutr. 2008 May;87(5):1254-61. doi: 10.1093/ajcn/87.5.1254. PMID: 18469247. https://pubmed.ncbi.nlm.nih.gov/18469247/

  (9) Debono M, Ghobadi C, Rostami-Hodjegan A, Huatan H, Campbell MJ, Newell-Price J, Darzy K, Merke DP, Arlt W, Ross RJ. Modified-release hydrocortisone to provide circadian cortisol profiles. J Clin Endocrinol Metab. 2009 May;94(5):1548-54. doi: 10.1210/jc.2008-2380. Epub 2009 Feb 17. PMID: 19223520; PMCID: PMC2684472. https://pubmed.ncbi.nlm.nih.gov/19223520/   

(10) Xuan Wang, Hao Ma, Qi Sun, Jun Li, Yoriko Heianza, Rob M Van Dam, Frank B Hu, Eric Rimm, JoAnn E Manson, Lu Qi, Coffee drinking timing and mortality in US adults, European Heart Journal, 2025;, ehae871, https://doi.org/10.1093/eurheartj/ehae871 

(11)  Nurk E, Refsum H, Drevon CA, Tell GS, Nygaard HA, Engedal K, Smith AD. Intake of flavonoid-rich wine, tea, and chocolate by elderly men and women is associated with better cognitive test performance. J Nutr. 2009 Jan;139(1):120-7. doi: 10.3945/jn.108.095182. Epub 2008 Dec 3. PMID: 19056649 https://pubmed.ncbi.nlm.nih.gov/19056649/ 

(12) Feng L, Chong MS, Lim WS, Lee TS, Kua EH, Ng TP. Tea for Alzheimer Prevention. J Prev Alzheimers Dis. 2015;2(2):136-141. doi: 10.14283/jpad.2015.57. PMID: 29231231. https://pubmed.ncbi.nlm.nih.gov/29231231/ 

(13) Cornelis MC, Weintraub S, Morris MC. Caffeinated Coffee and Tea Consumption, Genetic Variation and Cognitive Function in the UK Biobank. J Nutr. 2020 Aug 1;150(8):2164-2174. doi: 10.1093/jn/nxaa147. PMID: 32495843; PMCID: PMC7398783.  https://pmc.ncbi.nlm.nih.gov/articles/PMC7398783/