Easter is meant to follow on from Lent – 40 days of fasting. There lies the problem.
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‘We’ are the product of natural selection – survival of the fattest.
Those of us who can readily store carbs as fat through periods of famine have survived and become dominant. Now, there are no periods of famine, no ‘lent’ up, it’s just carbs all the way.
With one in six over 40 diabetic, the question is, are you heading in that direction?
Even raised glucose, but within the ‘normal’ range, in mid life increases Alzheimer’s risk by 14.5%.
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Why not find out?
We have a simple pinprick blood test to help you do just that. It measures the percentage of your red blood cells that are sugar-damaged or ‘glycosylated’. It’s called glycosylated haemoglobin, or HbA1c. This simple pinprick blood test is, in effect, measuring the total blood sugar spikes you experienced over the past three months (red blood cells, called haemoglobin, live for three months).
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What should you be aiming for?
Ideally, it should be 5% (31mmol/mol) or less. That’s healthy.
Above 5.4% (36) and in studies you can already pick up brain shrinkage and cognitive decline.
Above 6% (42) is considered pre-diabetic.
6.5% (48) or higher is considered diabetic.
For both brain and body health you certainly want it to be below 5.4%
(It’s measured slightly differently in the UK, in mmol/mol, which is the number shown in brackets.)
A recent study in Denmark of 20,000 people in their 60’s, published in the British Medical Journal [1], found that one in nine with an HbA1c of 6-6.1% developed diabetes in the next three years and one in five in the next five years. One in ten died.
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How to lower your score?
It is easy to lower, if you need to. But first, you need to know where you are starting from. Then you can retest three months later and find out if what you’ve done has worked.
But first, we suggest you measure your baseline HbA1c.
It’s more predictive of your blood sugar control than just your weight or waist circumference. In fact, it is the single most important measure of your glucose balance ‘resilience’ which is why it’s one of the four ‘essentials’ in our DRIfT test – the others being vitamin D, omega-3 and homocysteine (B vitamins).
We want to wish you a Healthy Easter by giving you £10 off your HBA1c test when you buy before Easter.
So that’s £39.95, not £49.95.
Also, if you book a repeat test in 3 months, which is how long it takes to ‘renew’ all your red blood cells, hopefully no longer sugar-coated, you’ll save a further 6%, bringing the cost down to £37.55, saving you £12.40 now and in 3 months time. That’s £24.80 in total. This offer ends on April 10th 2024.
Use the coupon code: easter at check out to save
(Discount applies to the HBa1c test only.)
Remember every test kit you order will not only help you upgrade your brain it will also help us in our vital research – you will become a part of our ‘Citizen Science’ team and be donating to our wider charitable work and research.
Thank you!
Thank you for reading!
Food for the Brain is a non-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.
Few people realise the catastrophic decline in mental health that has occurred over the past 50 years.
‘Brain health conditions have become a global health emergency,’ according to the Federation of European Neuroscience Societies last year (1).
The big question is: why?
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Introducing the four horsemen (recap)
I’m proposing that there are four main biological drivers of our demise which I’m calling the four horsemen of the mental health apocalypse: a lack of brain fats, messed up methylation, loss of glucose control and excessive oxidation.
The first two – brain fats and methylation – are vital for the integral structure of neuronal membranes.
The second two are vital for the function of brain cells, supplying fuel and coping with the oxidant ‘exhaust fumes’ of energy metabolism.
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Brain fuel
While omega-3 and B vitamins literally build a healthy brain, it is glucose and ketones that fuel it.
As a result of this process, oxidants are created which age the brain through the process of oxidation. Of course, oxidation can also occur through external causes, which is why smoking and air pollution are also established risk factors for Alzheimer’s.
Which leads us to the next two ‘horses of the mental health apocalypse’: the brain’s fuel supply and antioxidant protection. The brain consumes more energy than any other organ of the body. Neurons can only run on glucose or ketones. The irony is that the consequence of eating too many carbs and sugar is that the brain develops insulin resistance – effectively blocking the glucose from entering the mitochondria within the neurons. Starved of their energy source, we experience the consequences as mental fatigue and forgetfulness. According to Dr Robert Lustig, Emeritus Professor of Pediatrics at the University of California, San Francisco and a member of our Scientific Advisory Board, “This cognitive decline starts young. Cognitive decline in overweight children is associated with a high GL diet (1), and adolescents with metabolic dysfunction, driven by a high GL diet, have been shown to have shrinkage of the hippocampal area of the brain, as well as other structural changes and cognitive deficits (2).” This particular study showed actual shrinkage of the Alzheimer’s associated area of the brain in teenagers with metabolic syndrome as a consequence of too much sugar and ‘white’ carbs. The youngest age of an Alzheimer’s diagnosis, which requires proof of shrinkage of the hippocampal area of the brain, is age 19, in a young man in China who had no genetic risk factors (2).
It’s a biochemical storm.
As well as the fuel starvation that insulin resistance generates, the converse of blood sugar spikes, create Advanced Glycation End-products, or AGEs, that literally damage neurons. This ‘glycosylation’ is also seen in red blood cells, and why the HbA1c test which measures glycosylated haemoglobin is so good at predicting our health. If over 6.5% (or 48 mmol/mol) of these erythrocytes are sugar damaged, it’s a clear basis for a diabetes diagnosis. Just as for the omega-3 index, HbA1c is a reliable long-term measure showing the average sugar spikes over the past three months. You can assume what’s happening in the membranes of red blood cells is also happening to the neuronal membranes in the brain.
This is why the next brain essential is to measure HbA1c.
If 6.5% is the cut-off for a diabetes diagnosis, the ideal level is actually considerably lower. In what is usually considered to be the ‘normal range’, teenagers with HbA1c above 5.4% show cognitive decline and shrinkage of the hippocampus in the central area of the brain compared to those with lower HbA1c levels (3). “In teenagers with raised, but normal levels of HbA1c, there is clear evidence of the same kind of memory problems, and the same areas of brain shrinkage seen in patients with Alzheimer’s Disease” says Dr Robert Lustig.
Shrinkage of the hippocampus is the hallmark of Alzheimer’s and is used to diagnose the disease. A new study shows that 40-year-old adults with so-called normal glucose levels, but at the higher end of the normal range, have increased their risk of Alzheimer’s by 15%. (4)
A primary function of sleep is to repair all the neuronal membrane damage that occurs during the day. No sleep, no repair and the brain ages fast. This is mainly why lack of sleep is also a strong risk factor for Alzheimer’s.
There’s a growing interest in the role of ketogenic diets and ketone promoting supplements for brain health. Professor Stephen Cunnane, our expert in the new science of ‘keto therapeutics’ has shown that giving C8 oil or supplementing ketones can help to prevent Alzheimer’s, slow down cognitive decline, improve mood and lessen anxiety. His studies showed, in those with mild cognitive impairment, that taking 30g (two tablespoons) of mainly C8 oil, resulted in a 230% increased brain energy production from ketones with no change in energy derived from glucose (5), thus filling the ‘energy gap’ so often experienced by older people or those drifting towards insulin resistance. “Our research shows that the areas of the brain that have trouble using glucose for energy are able to use ketones perfectly well, even in moderately advanced dementia. This may explain why many people later in life who are given a supplement of C8 oil or MCT oil have improvements on a battery of cognitive tests. They often feel it brings their brain power back to life” says Cunnane.
Many people also report feeling calmer, less anxious and less depressed on ketogenic diets. A new book, Change Your Diet, Change Your Mind, out next month by psychiatrist Dr Georgia Ede digs deep into the growing evidence that a ketogenic diet, or at least one low in carbohydrates, is brain-friendly and helps people out of various mental health disorders. Or you can watch the recent webinar she did with us here.
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Antioxidant and polyphenol power
The more biologically active an essential fat is (with DHA at the top), the more prone it is to oxidation.
It is literally this ability of DHA to absorb energy (photons from light) that creates the impulse that passes information from the eye to the brain. It explains the origin of the brain and nervous system, going back a billion years to a rudimentary single cell called dynoflagellate. This little organism basically used the electric shock from photons to create the first ‘twitch’ towards light. Where there was light, there was food, and ultimately the evolution of the nervous system and brain. In simple terms, we can see that the brain is really an extension of the eye. How do we see with such precision and speed? Until now, no-one has been able to explain this satisfactorily. At the age of 93, Professor Michael Crawford, who helped our charity get started, has worked out how this occurs and how we see in colour. It requires knowledge of quantum physics, explained in a recent paper entitled ‘Docosahexaenoic Acid Explains the Unexplained in Visual Transduction’.(6)
With all this volatile fatty acid and mitochondrial energy production, cleaning up the oxidant exhaust fumes is a vital function for a healthy brain. So how do we achieve protection and how do we measure it?
There are hundreds, if not thousands of antioxidants and polyphenols in our food. Foods can be measured for their ‘Total Antioxidant Capacity’ or TAC for short. It’s worked out from an equation involving eight key antioxidants from vitamin A, carotenes (think carrots), lycopenes (rich in tomatoes), lutein and zeaxanthine (rich in green vegetables), vitamin E (in nuts and seeds), but most of all vitamin C (rich in berries, broccoli, peppers and other vegetables).
Vitamin C is a keystone nutrient as far as swinging the antioxidant equation in our favour. Individually, the impact of these nutrients on our health may be less than when combined. For example, a study of 4,740 Cache County Utah elderly residents found that those supplementing both vitamin E and C cut their risk of developing Alzheimer’s by two thirds (66%). Taking just one cut the risk by a mere quarter (25%). (7)
The higher the TAC score of our diet, the lower our risk of memory decline becomes. This was the finding of a recent study of 2,716 people over age 60. Higher TAC scores correlated with better memory function (8). Those in the highest quarter of TAC scores had half the risk of decreasing memory. Powerful stuff!
Tea, cacao, red wine, red onions, olives and berries are rich sources of polyphenols. Many of these polyphenol-rich foods improve circulation, lower blood pressure and dampen down inflammation which lies behind many brain and heart health problems.
More than a decade ago research in Norway (9) found that the more tea you drink the better; a small glass of wine (125ml) a day (preferably red, as it is rich in resveratrol) reduces the risk of cognitive decline. Cacao is also beneficial, ideally no more than 10g, (about 3 pieces) of dark, 70 percent or more. Other studies based on adding cacao to the diet have shown improved cognition, possibly by improving circulation. This was recently confirmed in a big ‘COSMOS’ trial involving over 20,000 people given a cacao extract supplement versus a placebo for five years (10). The reduction in cardiovascular risk was even greater than that of a Mediterranean diet.
The take-away message? Polyphenols are a vital part of a healthy diet for both our heart and our brain.
So, what do we need to eat and drink to protect our brain and body? Basically, eat a Mediterranean-style ‘rainbow coloured’ diet. A Mediterranean diet has more fish, less meat and dairy, more olive oil, fruit and vegetables including tomatoes, legumes (beans and lentils), and whole grain cereals than a standard Western diet. It also includes small quantities of red wine. There are variations of this kind of diet, called the MIND diet and the DASH diet, but the core components are the same. As researchers drill down, we are learning what to eat and drink and how much, to keep our minds sharp and brain young.
The trick is to really start thinking of the colours we are eating and gravitate to the strong colours, choosing organic where possible. Mustard and turmeric, for example, are strong yellows. Bright oranges include butternut squash, sweet potato, carrots. For red, think tomatoes and watermelons. Anything purple, magenta or blue is brilliant for us too. From beetroots (eat them raw, grated into salads) to blueberries, blackberries to raspberries, all these foods are fantastically good for us, so tuck in!
In addition to food, as a health aspiring 65-year-old, I both supplement 1 gram of vitamin C twice a day and take an AGE Antioxidant containing Co-Q10, alpha lipoic acid, n-acetyl cysteine (NAC – as a precursor to glutathione which is the master antioxidant) and resveratrol as well as vitamin E and A – both beta-carotene and retinol. Many people think that there is no point supplementing glutathione because it is so rapidly oxidised, or sacrificed, to disarm oxidants, but it is also rapidly recycled by anthocyanidins in blue/red berries. So, combining the two reloads glutathione. This film shows how.
But how do we measure our antioxidant status?
My research team is working on exactly this challenge and we are finding that the ratio between reduced glutathione (GSH) and oxidised glutathione (GSSG) in red blood cells is probably the best biological determinant. We hope to introduce that into our panel of functional indicators, and research how it correlates with dietary intake and lifestyle habits as well as cognitive function.
We are due to launch a DRIfT Test as part of a global prevention initiative, which will be a 4 in 1 test
The UK Biobank has collected data on 500,000 people since 2006, inviting people to fill in questionnaires, give blood and carry out certain tests. We are funded by ‘Friends’ who pay £50/$60/€60 a year. So far we have collected data on 410,000 people and this number is growing by about a hundred a day.
In addition to taking the blood test, participants are invited to complete a validated online Cognitive Function Test (not a questionnaire), followed by a comprehensive 144 question Dementia Risk Index diet and lifestyle questionnaire which takes 20-25 minutes. This works out a person’s future risk and shows what’s driving the risk. This is a free service.
We run the UK’s leading dementia prevention charity which is running the prevention project together with Dr Tommy Wood, Assistant Professor at the University of Washington. “By tracking a person’s blood sugar, vitamin B, D and omega-3 status against changes in cognitive function over time, in addition to lifestyle factors such as sleep and physical activity, we can learn what really helps prevent cognitive decline.” says Dr Wood, the principal investigator for the study.
Citizen Science
All donations are put back into research, and the results of the research are shared back to the people.
This is science for the people, funded by the people, shared back with the people. We call them Citizen Scientists and we hope to reach a million people around the world within a year or so making this the biggest prevention-focussed study of its kind. The purpose of research is to help people. Too often great scientists do great studies, which get published and ignored. We have to face the fact that, in the UK as an example, the Government has commissioned four reports on mental health and Wellcome did a further independent report, all showing we have a cerebral tsunami with brain and mental health disorders ahead of every other disease.
They have ignored every single one.
Change is not going to come from the Government or the NHS. It is going to have to come from us, the people. I urge everyone in natural medicine to take the test themselves, share it with others and support us by becoming Friends and donating £50 a year, getting so much in return.
This is how we are funding our amazing research team. We are a lean, keen, small but mighty team.
Every donation, big or small, goes right back into helping people prevent these preventable and terrible diseases such as dementia.
Together, we can change the world.
We need to because time is running out.
We will lose our humanity if we don’t stop this brain drain.
Food for the Brain is a non-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 Lakhan, S.E., Kirchgessner, A. The emerging role of dietary fructose in obesity and cognitive decline. Nutr J 12, 114 (2013).
7 Basambombo LL, Carmichael PH, Côté S, Laurin D. Use of Vitamin E and C Supplements for the Prevention of Cognitive Decline. Ann Pharmacother. 2017 Feb;51(2):118-124. doi: 10.1177/1060028016673072. Epub 2016 Oct 5. PMID: 27708183.
8 Peng, M., Liu, Y., Jia, X. et al. Dietary Total Antioxidant Capacity and Cognitive Function in Older Adults in the United States: The NHANES 2011–2014. J Nutr Health Aging 27, 479–486 (2023). https://doi.org/10.1007/s12603-023-1934-9
9 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.
10 Sesso HD, Manson JE, Aragaki AK, Rist PM, Johnson LG, Friedenberg G, Copeland T, Clar A, Mora S, Moorthy MV, Sarkissian A, Carrick WR, Anderson GL; COSMOS Research Group. Effect of cocoa flavanol supplementation for the prevention of cardiovascular disease events: the COcoa Supplement and Multivitamin Outcomes Study (COSMOS) randomized clinical trial. Am J Clin Nutr. 2022 Jun 7;115(6):1490-1500. doi: 10.1093/ajcn/nqac055. PMID: 35294962; PMCID: PMC9170467.
Back in the decade that gave us neon shell suits, the first space shuttle, and the birth of the pop video (the unforgettable 1980s) we also believed that glucose (the sugar used by our bodies) gave us extra energy. Lucozade, a liquid form of glucose with a good dose of preservatives, artificial sweeteners and artificial colourants, was advertised as ‘energy for the human race.’
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Yet, new studies are showing that too much glucose, and especially fructose, over time starves the brain of energy, leading to both memory loss and brain shrinkage.
These two sugars interfere with the energy factories within cells, called mitochondria, and deprive the brain of the energy it needs to function properly.
The link between diabetes and dementia is well known – those with diabetes have four times the risk of dementia.
Haemoglobin A1c (HbA1c) is a long-term measure of glucose bound to red blood cells (haemoglobin) and is used by doctors to diagnose diabetes and monitor its therapy. HbA1c is a measure of damage produced by sugar spikes on red blood cells; a HbA1c of 6.5% or greater is diagnostic of diabetes. But long before this, in what is usually considered to be the ‘normal range’ teenagers with HbA1c above 5.4% show cognitive decline and shrinkage of the hippocampus in the central area of the brain compared to those with lower HbA1c levels (1).
Shrinkage of the hippocampus is the hallmark of Alzheimer’s and is used to diagnose the disease. A new study shows that 40-year-old adults with so-called normal glucose levels, but at the higher end of the normal range, have increased their risk of Alzheimer’s by 15% (2).
Furthermore, “In teenagers with raised, but normal levels of HbA1c, there is clear evidence of the same kind of memory problems and the same areas of brain shrinkage seen in patients with Alzheimer’s Disease” says Robert Lustig, Emeritus Professor of Pediatrics at University of California, San Francisco.
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“Keeping your HbA1c below 5.4% with a no-added-sugar diet, and for some a low-carbohydrate diet, is one of the most direct ways you can protect your brain at any age.” says Lustig.
“The irony is that having too much sugar over a number of years makes a person resistant to insulin. We need insulin in order to deliver glucose into our brain cells, so insulin resistance, the direct consequence of too much glucose, ends up starving the brain of energy with the consequent loss of concentration and memory.” says nutritionist and psychologist Patrick Holford, our CEO and founder.
“We are calling for people to test both their cognitive function with our free online test and measure their HbA1c with our new home pin prick blood test kit, so we can really find out when problems occur and how to prevent cognitive decline.” So far, over 400,000 people have done our Cognitive Function Test – our FREE, validated, online cognitive function test which tells you your future dementia risk and what to do to lower it.
Professor Robert Lustig thinks the problem got even worse when the food industry switched from sucrose, derived from cane, to high-fructose corn syrup, derived from corn; “High-fructose corn syrup is not more biologically evil; it’s economically evil, because it’s half the price of sucrose, so it found its way into all sorts of foods…
“The key message is to test HbA1c early if it is over 5.4% and act to bring it down by cutting right back on foods and drinks with added sugar including carbohydrate-rich foods such as bread, rice, pasta, potatoes, and especially fruit juice. Nature never provides fructose without the requisite fibre. When God made the poison, he packaged it with the antidote. Eat your fruit, don’t drink it.” says Lustig.
Thank you for reading! Food for the Brain is a non-for-profit educational and research charity that offers a freeCognitive Function Testand assesses your Dementia Risk Index to be able to advise you on how to dementia-proof your diet and lifestyle.
By completing theCognitive Function Testyou 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.
What does any animal, perhaps your dog, do after exercising or going for a walk?
Sleep.
Sleep is how the brain recovers. There is now overwhelming evidence that sleep is a ‘brain essential’ and just like Goldilocks, it seems we need just the right amount. Getting too much, or too little, increases our risk for cognitive decline.
The optimal amount of sleep for brain health appears to be a total of seven hours. This does not necessarily need to be in one uninterrupted stretch – a study found that napping after physical activity can reduce the risk of cognitive impairment (1).
However, those consistently getting less than seven hours of sleep may be doubling their risk of age-related cognitive decline (2). A UK study of Whitehall civil servants, which began in the 1980s, found that persistent short sleep at ages 50, 60, and 70 was associated with a 30% increased risk of dementia (3). Sleep loss does not just increase long-term dementia risk – it also reduces empathy, increases negative emotions, and impairs next-day functioning (4).
Why Sleep Is Essential to Brain Health?
Think of sleep as the brain’s housekeeper. During sleep, circulation of blood and cerebrospinal fluid improves, helping to clear out waste products from brain metabolism (5). These include harmful oxidants and amyloid protein, the latter linked to Alzheimer’s and brain inflammation – which can begin accumulating after just one night of poor sleep (6).
One key agent in this nightly brain cleanse is melatonin. As night falls, our brains convert serotonin into melatonin, primarily in the pineal gland – referred to by Descartes as the seat of the soul, and known in yoga as the ‘third eye’ chakra.
Sensitive to light via receptors behind the eyes, the pineal gland is the only endocrine organ in direct contact with the external world. Darkness triggers melatonin production, while exposure to light – including screen use before bed – suppresses it.
Melatonin helps keep us in sync with the circadian cycle. Some frequent flyers even use melatonin supplements to overcome jet lag and adjust their sleep rhythms more easily (7).
More than just a sleep aid, melatonin acts as a powerful antioxidant – disarming damaging oxidants, restoring mitochondrial energy production, and acting as an anti-inflammatory. It has been used to support recovery in cancer, COVID-19, and cardiovascular conditions (8,9). Reduced brain melatonin levels and circadian disruption are also observed in individuals with cognitive decline.
Why Dreaming Matters?
Sleep isn’t just for rest – it’s a deeply active process. About 30 minutes after falling asleep, we enter deep sleep, marked by slower breathing, a reduced heart rate, and lower blood pressure. This phase restores and repairs bodily tissues. About 90 minutes in, we shift into REM (rapid eye movement) sleep – where most dreaming occurs.
REM sleep is critical for brain health. Each night, we cycle between deep, light, and REM sleep three to five times, with REM ideally making up about 25% of total sleep.
REM and deep sleep phases also see increased production of growth hormone, which supports tissue repair. Meanwhile, melatonin helps clear metabolic waste. However, under stress, cortisol levels rise and suppress REM sleep and growth hormone production, reducing the brain’s ability to recover. Sleep-deprived individuals tend to experience more REM when they finally do sleep, suggesting REM plays a key role in emotional processing.
One theory suggests that dreams help us metabolise suppressed emotions – fear, anger, sadness – stored during our busy days. If you have a vivid, emotional dream, it may be worth tracing it back to unresolved feelings from the previous day.
How Chronic Stress Disrupts Sleep and Brain Function?
Chronic or intense stress – such as bereavement, illness, or financial strain – has been shown to increase the risk of cognitive decline and dementia (10). However, good sleep can help process a stressful day.
The perception of control matters, too. Studies show that high job demands combined with low control are strongly linked to an increased risk of depression and cognitive impairment (11). Examples might include caregiving for a loved one with dementia while navigating health services, or working in a high-stress job without the resources to make meaningful changes.
Your Brain on Cortisol: The Hippocampus Feedback Loop
Two hormones mediate stress: adrenaline (short-acting) and cortisol (longer-acting). Adrenaline prepares you to act quickly – it’s the fight-or-flight hormone. Cortisol helps regulate energy and alertness throughout the day.
In the morning, cortisol naturally rises to get us going. It should fall in the evening to support sleep. But chronic stress disrupts this rhythm. If cortisol stays high at night, sleep is disturbed. If it’s too low in the morning, you may feel foggy and reach for caffeine.
Excess cortisol impairs memory, slows thinking, lowers social functioning, and raises the risk of dementia (12). What’s happening in the brain is that cortisol overstimulates the hippocampus, which is responsible for memory and emotional regulation. With prolonged stress, this feedback loop fails – the hippocampus shrinks, and cortisol levels remain elevated, accelerating brain ageing.
Short-Term Relief, Long-Term Harm: Sugar and Alcohol as Stress Crutches
Oscar Ichazo described how we reach for compensations under stress. Unfortunately, many – like alcohol and sugar – backfire.
Alcohol temporarily boosts GABA, calming the nervous system and reducing adrenaline. But the effect is short-lived. Drinking too much reduces GABA receptor sensitivity the next day, leaving us more anxious. In the long term, alcohol is neurotoxic and increases dementia risk (12). It also disrupts sleep architecture, impairing the brain’s ability to repair itself.
Sugar triggers dopamine and activates the brain’s reward circuits, making us crave more. It also spikes the adrenal system, amplifying stress and cortisol levels (13). Fats and proteins do not have this effect – this is unique to sugar.
So, when we use sugar or alcohol to manage stress, we often wake up feeling more anxious and foggy. This leads us to reach for caffeine and more sugar, which spikes cortisol again, leaving us even more depleted by evening – creating a cycle of stress, poor sleep, and accelerated brain ageing.
Simple Ways to Break the Cycle
The good news? You can reverse this pattern. Start here:
Become a FRIEND and get access to your personalised COGNITION® programme which which includes: – A whole module dedicated to sleep and calm – Another focused on helping you reduce sugar – Plus monthly live group coaching to help you stay focused and on track
Prioritise seven hours of quality sleep each night.
Identify and reduce common stress triggers.
Be mindful of alcohol and sugar intake.
Find positive outlets: yoga, walking, journaling, a good book – like Upgrade Your Brain.
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Thank you for reading! Food for the Brain is a non-for-profit educational and research charity that offers a freeCognitive Function Testand assesses your Dementia Risk Index to be able to advise you on how to dementia-proof your diet and lifestyle.
By completing theCognitive Function Testyou 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.
1 Qian YX, Ma QH, Sun HP, Xu Y, Pan CW. Combined effect of three common lifestyle factors on cognitive impairment among older Chinese adults: a community-based, cross-sectional survey. Psychogeriatrics. 2020 Nov;20(6):844-849. doi: 10.1111/psyg.12604. Epub 2020 Aug 31. PMID: 32869429.
2 Bubu OM, Brannick M, Mortimer J, Umasabor-Bubu O, Sebastião YV, Wen Y, Schwartz S, Borenstein AR, Wu Y, Morgan D, Anderson WM. Sleep, Cognitive impairment, and Alzheimer’s disease: A Systematic Review and Meta-Analysis. Sleep. 2017 Jan 1;40(1). doi: 10.1093/sleep/zsw032. PMID: 28364458.
3 Sabia S, Fayosse A, Dumurgier J, van Hees VT, Paquet C, Sommerlad A, Kivimäki M, Dugravot A, Singh-Manoux A. Association of sleep duration in middle and old age with incidence of dementia. Nat Commun. 2021 Apr 20;12(1):2289. doi: 10.1038/s41467-021-22354-2. PMID: 33879784; PMCID: PMC8058039.
4 Krause AJ, Simon EB, Mander BA, Greer SM, Saletin JM, Goldstein-Piekarski AN, Walker MP. The sleep-deprived human brain. Nat Rev Neurosci. 2017 Jul;18(7):404-418. doi: 10.1038/nrn.2017.55. Epub 2017 May 18. PMID: 28515433; PMCID: PMC6143346.
56 Xie L, Kang H, Xu Q, Chen MJ, Liao Y, Thiyagarajan M, O’Donnell J, Christensen DJ, Nicholson C, Iliff JJ, Takano T, Deane R, Nedergaard M. Sleep drives metabolite clearance from the adult brain. Science. 2013 Oct 18;342(6156):373-7. doi: 10.1126/science.1241224. PMID: 24136970; PMCID: PMC3880190.
6 Shokri-Kojori E, Wang GJ, Wiers CE, Demiral SB, Guo M, Kim SW, Lindgren E, Ramirez V, Zehra A, Freeman C, Miller G, Manza P, Srivastava T, De Santi S, Tomasi D, Benveniste H, Volkow ND. β-Amyloid accumulation in the human brain after one night of sleep deprivation. Proc Natl Acad Sci U S A. 2018 Apr 24;115(17):4483-4488. doi: 10.1073/pnas.1721694115. Epub 2018 Apr 9. PMID: 29632177; PMCID: PMC5924922.
7 Herxheimer A, Petrie KJ. Melatonin for the prevention and treatment of jet lag. Cochrane Database Syst Rev. 2002;(2):CD001520. doi: 10.1002/14651858.CD001520. PMID: 12076414.
8 Keithahn C, Lerchl A. 5-hydroxytryptophan is a more potent in vitro hydroxyl radical scavenger than melatonin or vitamin C. J Pineal Res. 2005 Jan;38(1):62-6. doi: 10.1111/j.1600-079X.2004.00177.x. PMID: 15617538.
9 Chitimus DM, Popescu MR, Voiculescu SE, Panaitescu AM, Pavel B, Zagrean L, Zagrean AM. Melatonin’s Impact on Antioxidative and Anti-Inflammatory Reprogramming in Homeostasis and Disease. Biomolecules. 2020 Aug 20;10(9):1211. doi: 10.3390/biom10091211. PMID: 32825327; PMCID: PMC7563541; regarding covid see also Tan DX, Reiter RJ. Mechanisms and clinical evidence to support melatonin’s use in severe COVID-19 patients to lower mortality. Life Sci. 2022 Apr 1;294:120368. doi: 10.1016/j.lfs.2022.120368. Epub 2022 Jan 30. PMID: 35108568; PMCID: PMC8800937.; see also Begum R, Mamun-Or-Rashid ANM, Lucy TT, Pramanik MK, Sil BK, Mukerjee N, Tagde P, Yagi M, Yonei Y. Potential Therapeutic Approach of Melatonin against Omicron and Some Other Variants of SARS-CoV-2. Molecules. 2022 Oct 16;27(20):6934. doi: 10.3390/molecules27206934. PMID: 36296527; PMCID: PMC9609612.; regarding cancer see Reiter RJ, Rosales-Corral SA, Tan DX, Acuna-Castroviejo D, Qin L, Yang SF, Xu K. Melatonin, a Full Service Anti-Cancer Agent: Inhibition of Initiation, Progression and Metastasis. Int J Mol Sci. 2017 Apr 17;18(4):843. doi: 10.3390/ijms18040843. PMID: 28420185; PMCID: PMC5412427.
10 Franks KH, Bransby L, Saling MM, Pase MP. Association of Stress with Risk of Dementia and Mild Cognitive Impairment: A Systematic Review and Meta-Analysis. J Alzheimers Dis. 2021;82(4):1573-1590. doi: 10.3233/JAD-210094. PMID: 34366334.
11 Wang HX, Wahlberg M, Karp A, Winblad B, Fratiglioni L. Psychosocial stress at work is associated with increased dementia risk in late life. Alzheimers Dement. 2012;8(2):114-20. doi: 10.1016/j.jalz.2011.03.001. PMID: 22404853; see also Gonzalez-Mulé, E., & Cockburn, B. S. (2021). This job is (literally) killing me: A moderated-mediated model linking work characteristics to mortality. Journal of Applied Psychology, 106(1), 140–151. https://doi.org/10.1037/apl0000501; see also Gonzalez-Mulé E, Kim MM, Ryu JW. A meta-analytic test of multiplicative and additive models of job demands, resources, and stress. J Appl Psychol. 2021 Sep;106(9):1391-1411. doi: 10.1037/apl0000840. Epub 2020 Sep 21. PMID: 32955269.
12 Ouanes S, Popp J. High Cortisol and the Risk of Dementia and Alzheimer’s Disease: A Review of the Literature. Front Aging Neurosci. 2019 Mar 1;11:43. doi: 10.3389/fnagi.2019.00043. PMID: 30881301; PMCID: PMC6405479.13 Gonzalez-Bono E, Rohleder N, Hellhammer DH, Salvador A, Kirschbaum C. Glucose but not protein or fat load amplifies the cortisol response to psychosocial stress. Horm Behav. 2002 May;41(3):328-33. doi: 10.1006/hbeh.2002.1766. PMID: 11971667.
We now know that today’s diet, lacking in brain-friendly fats and other nutrients, yet high in sugar and ultra-processed food, is likely to be shrinking our brains, dumbing us down and triggering a big increase in mental health problems. But it isn’t just nutrition that is creating the perfect storm for our mental demise.
The digital culture we exist in is pushing us towards a whole new paradigm of background stress. This is partly because the marketeers have learnt how to get us addicted to their products – applying a level of stress and variable reward to trick the brain’s reward system – leaving you with a ‘gotta have it’ feeling.
This mechanism of ‘variable reward’
This was first discovered in the 1930’s by the psychologist B.F. Skinner. He found that mice responded most frequently to reward-associated stimuli when the reward was given after a varying number of responses – so the animal didn’t know when it would get the prize. It seems we are no different; if we perceive a reward to be delivered at random, and if checking for that reward comes at little or no cost, we end up checking habitually.
So is this where smartphone addiction comes from?
This manipulation of the stress/reward response is one of the oldest mechanisms of the brain. It is both core for our survival, but also makes us more impulsive, manipulatable and, effectively, stupid.
Most of all, it makes us good consumers. Reward, based on dopamine, equals pleasure. We are living in space-age times with stone age minds and multinational companies have learnt how to get us hooked – literally neurochemically addicted to consuming their products.
We are being sold pleasure in the guise of happiness: the happy hour, the happy meal, happiness in a can. But joy and happiness are regulated by the neurotransmitter serotonin, not the latest special offer. And in fact, this pleasure-seeking may be counterproductive.
“The more pleasure you seek, the more unhappy you get” says Professor Robert Lustig, author of ‘Hacking the American Mind’. This is because too much dopamine (the ‘reward’ neurotransmitter) suppresses serotonin (the ‘happy’ neurotransmitter) and we end up feeling unhappy and depressed. This brain hijack may be why depression, suicide and psychiatric drug prescriptions have rocketed to the point where, in the UK and US (and probably elsewhere), there are almost twice as many prescriptions for psychiatric drugs per year than there are people.
“We are the most in debt, the most obese, the most medicated and the most drugged up adult population in human history” says Lustig. We have literally learnt how to fool our brains and in doing so have fooled ourselves, by creating addictive behaviours and addictive foods.
An example of this is what happens in your brain if you eat sugar and/or fat.
Sugar…just like cocaine and heroin?
Sugar, just like cocaine and heroin, stimulates dopamine and endorphins. It triggers the reward system but with overuse, leads to reward deficiency (1). Dr Candace Pert, Research Professor in the Department of Physiology and Biophysics at Georgetown University Medical Center in Washington DC, and author of the seminal book ‘The Molecules of Emotion’, was the first to point this out in no uncertain terms: “I consider sugar to be a drug, a highly purified plant product that can become addictive. Relying on an artificial form of glucose – sugar – to give us a quick pick-me-up is analogous to, if not as dangerous as, shooting heroin. (2)” At the time, this was heresy but, today, most people are well aware of this. But it’s not just sugar that’s feeding our addiction.
Neuropharmacologist Professor Paul Kenny, a Dubliner now working in his Manhattan lab at Mount Sinai Hospital, discovered this when he started feeding rats different diets. When he fed one group of rats either lots of sugary foods and another group lots of fatty foods, neither group would gain much weight. They’d control their intake and it would take over a month to see a small weight gain.
However, when he fed them a combination of 50% sugar and 50% fat, such as in a cheesecake, he noted the mice would “dive head first into a slice and gorge so vigorously that it covered its fur in blobs. It’s not pleasant.” After a binge on cheesecake they continued to graze, constantly eating food, he says, as if the off-switch telling them they were full had malfunctioned. “It completely changed them.” They stopped exercising and gained significant weight after only seven days. They also became addicted (3). When he took away the junk food and replaced it with healthy food they went on a hunger strike, refusing to eat it.
He even tried to stop them by giving them an electric shock to their feet. “We then warned the rats as they were eating—by flashing a light—that they would receive a nasty foot shock. Rats eating the bland chow would quickly stop and scramble away, but time and again the obese rats continued to devour the rich food, ignoring the warning they had been trained to fear. Their hedonic desire overruled their basic sense of self-preservation.”
Overeating, he found, juices up the reward systems in the brain — so much so, that in some people, it can overpower the brain’s ability to tell them to stop eating when they have had enough. As with alcoholics and drug addicts, the more they have, the more they want, creating a vicious cycle of dopamine resistance, eventually leading to the brain’s receptors for dopamine to shut down.
It seems dopamine, the brain’s main neurotransmitter of reward and desire, is the key.
Obese people and drug addicts have been shown to have less dopamine D2 receptors (D2R)s (4). People who are born with reduced levels of D2R are therefore at greater genetic risk of developing obesity and drug addiction – so you can be genetically predisposed to addiction. Researchers at Brookhaven National Laboratory and the Oregon Research Institute have shown that the reward system in obese people responds weakly to food, even to junk food(5). How does an individual overcome this absence of pleasure? By eating more pleasure foods to gain a temporary boost, thereby perpetuating the cycle. The researchers found that obese people may overeat just to experience the same degree of pleasure that lean individuals enjoy from less food.
Nicole Avena of the University of Florida, and others, have found that particular fats or sugars, sugars together with fats, and possibly salt, are the most addictive (6). A study by Professor David Ludwig of Boston Children’s Hospital suggests that highly processed, quickly digested fast carbs could trigger cravings (7). But research overall indicates that no one ingredient stokes food addiction better than the combo of fats and sugars, high in calories. Nature just doesn’t make these kinds of foods. Only the food industry does.
Similarly, cola drinks combine the stimulant caffeine, with sugar and salt, to make you drink more. And we crave sugary food and drink even more when fructose is used instead of glucose. Why? Because our cells run on glucose and quickly feedback when we’ve had enough. Fructose (or high fructose corn syrup, derived from corn) takes longer to send us that signal, leading us to consume more. No wonder then that glucose has been replaced by fructose and is a key ingredient in today’s ultra-processed foods.
Are you addicted to your smartphone?
Of all the changes that have taken place in the 21st century, the ‘digital revolution’ has changed our world beyond recognition, seemingly speeding up time. Yes, our diet and environment have changed a lot, but what’s really changed, especially in cities that now house half of humanity and an estimated two-thirds of the world’s population by 2035, is the pace of life. People all over the world are sleeping less, having less downtime, feeling more anxious and stressed and burning out at a far higher rate. This is reflected in the increasing rate of work absenteeism, depression and suicide, especially in cities.
The speeding up of communication – emails, smartphones and digital media – means that we are supposed to react to demands, and are bombarded with them, at an ever-increasing speed.
We have literally become addicted to our phones(8). The average person picks up their phone 352 times a day – more than every three minutes, and swipes it thousands of times a day. A UK survey reports 62% cannot make it through dinner without checking their phone. Almost half of us report anxiety if we don’t have our phone, or a signal, suffering ‘nomophobia’. We are going to sleep with our phones and checking them first thing on waking up. One survey found that one in ten university students in the US admitted to having checked their smartphones during sex!
Why? Basically, to sell stuff. “I feel tremendous guilt,” admitted Chamath Palihapitiya, former Vice President of User Growth at Facebook, to an audience of Stanford students. “The short-term, dopamine-driven feedback loops that we have created are destroying how society works.” Whether it’s Facebook, Instagram, Twitter, Snapchat, LinkedIn or any other platform, the core design is to get your attention, then show you ads tailored to your attributes and behaviours which the technology learns about you. Facebook, for example, has learnt how to do this with prompts, swipe downs, red icons that you press and don’t know what you receive. Is it a ‘like’? Do I have more ‘friends’? Or has another person ‘linked’ to me on LinkedIn etc.
Facebook even knows when you’re feeling ‘insecure’, ‘worthless’ and ‘need a confidence boost’ or are ‘bored’, and can make sure you receive a notification of a ‘like’ at just the right time to keep you hooked. If you find yourself checking your phone at the slightest feeling of boredom, purely out of habit, know that programmers work very hard behind the screens to keep you doing exactly that. A study of 143 undergraduates at the University of Pennsylvania, limiting use to 30 minutes a day versus a control group found significant reductions in loneliness and depression (9). The researchers concluded, “Our findings strongly suggest that limiting social media use to approximately 30 minutes per day may lead to significant improvement in well-being.”
Whether it’s a text, a notification or a ‘like’, just like sugar, this digital consumption triggers a reward signal in our brains. The marketing algorithms schedule the precise times to deliver our digital diet and serve up the extra addictive quality of a variable reward.
Your brain’s reward system
It’s to do with a tiny organ in the central hippocampal area of the brain called the nucleus accumbens. This is the headquarters of our dopamine-based ‘reward’ system.
The more dopamine you release the more receptors shut down, so you seek more pleasurable behaviours and foods. Insidiously and unknowingly your brain has been hijacked and the symptoms you feel are the direct consequences of an intended addiction. Gambling, gaming, overeating, sex, drugs, food, social media and other digital addictions are all part of it. We end up needing this constant stimulation and, to fuel that, need instant energy foods and drinks – sugar and coffee.
Alcohol – the opiate of the masses
Whether you’ve become addicted to sugar, food, caffeinated drinks, social media, gambling, gaming or non-stop stimulation, or simply get caught in the stress trap, perhaps due to work and life demands and debts, this often results in an inability to switch off with a background feeling on anxiety and stress without alcohol, and difficulty sleeping.
You may find, in time, that your need for alcohol increases – from a glass a night to two, three, half a bottle or even more. Alcohol, a well-established neurotoxin (10), surely is the opiate of the masses. Consumption keeps going up. It’s the currency of a good time, normalised as a response to stress, glorified in movies and at the core of our modern culture, with a 1.5 trillion dollar industry, expected to rise to 2 trillion by 2027 (11), promoting its use. While smoking has become frowned upon, anything other than heavy drinking is considered socially acceptable. Yet according to WHO alcohol is in the top five causes of death and disability, and has become the most common cause of death in men under 50 (and soon will be for women), accounting for one-fifth of all deaths under 50 and almost 30,000 deaths a year overall, roughly a third that of smoking and ten times more than opioids (inc heroin) and is ranked more harmful than any other drug, including opioids (12). This addictive drug is so socially acceptable that governments avoid attempts to curtail its use for fear of voter reprisals.
A commonly unknown fact is that death or disability from alcohol doesn’t only occur in heavy drinkers. The risk goes up exponentially with the quantity you drink. The good news is that small reductions have big positive effects on your health. To make this real, a 12.5% vol. bottle of wine contains 75g alcohol: drinkers who have 2/3rds of a bottle of wine (two large glasses) or the equivalent 50g of alcohol, have a lifetime risk of death of 16%. But one medium glass (175ml) of wine (17.5g of alcohol) brings that risk below 1%. In terms of mitigating serious health risks, including death, the advice of the UK government’s former advisor, Professor David Nutt, is for women to consume no more than 15g of alcohol per day and for men no more than 20g alcohol per day, and to have at least two alcohol-free days per week. Sadly, Professor Nutt was sacked for saying that alcohol was a ‘time bomb’ and more dangerous than Ecstasy, but the statistics point to this being true.
The trouble is, when you get stuck in the cycle of seeking rewards, needing stimulants and relaxants, you become more tired, more anxious and may even have started to feel more depressed.
When things get bad and you visit your doctor they may prescribe antidepressants, tranquillisers (short-term use only) or sleeping pills. Others learn to use illicit uppers and downers.
Are you addicted to stimulants?
The other major acceptable and glorified drug is caffeine, mainly in the form of coffee, although many people don’t realise that strong tea has as much caffeine as a regular cup of coffee. Like sugar, alcohol and our digital diet, it stimulates dopamine release and the feeling of pleasure or reward. Imagine a day with no coffee, tea, sugar, chocolate or that well-earned glass of something! If you shout, ‘No way!’ there is a very real possibility that you have some level of addiction to these stimulants. This can range from a mild addiction that you can live with quite happily to a major problem that is controlling your life.
However, whatever the level of addiction, the net consequence is always less energy, not more. One of my clients, Bobbie, serves as a case in point. She was already eating a healthy diet and took a sensible daily programme of vitamin and mineral supplements. She had only two problems: a lack of energy in the morning and occasional headaches. She also had one vice: three cups of coffee a day. After some persuasion, she agreed to stop the coffee for a month. To her surprise, her energy levels rose and the headaches stopped.
Like Bobbie, it’s useful to audit your stimulant consumption from time to time. Using a Stimulant Inventory below can be helpful, but in making an accurate assessment of your current relationship to stimulants, you need to be honest with yourself about how you use them. There’s a space for alcohol which, while not a stimulant, still triggers those dopamine receptors.
It’s useful to write down the time of day you consume the above and to spend time thinking about what your relationship to these substances is.
Do you, for example, ever buy sweets and hide the wrappers so other people don’t know you’ve eaten them?
Do you swoon at the dessert menu in restaurants?
How much do you think about and look forward to that morning cup of coffee or a mid-morning second cup?
How important is that drink after work?
Does everyone really know how much you smoke?
Have you cranked up your caffeine intake to ‘double espresso’ equivalent drinks using more coffee at home than you used to?
Do you need more to get a ‘kick’ if you even get one, or does coffee now just relieve the fuzzy tiredness you feel without it?
This kind of relationship to stimulants, often cloaked in an attitude that they are just some of the innocent pleasures of life, is indicative of an underlying chemical imbalance that depletes your energy and peace of mind and, at its worst, feeds into mental health issues.
Coffee and Caffeine Withdrawal and Sleep
If you wake up feeling good and can function without a coffee, and have no major mental health issues, sleeping well for example, but enjoy one coffee a day which will give you a dopamine kick, that’s not a problem. The best measure of your relationship with coffee or caffeine, and whether your brain has ‘downregulated’ dopamine and adrenaline receptors is what happens when you quit. If the answer is nothing then there’s no issue. If, on the other hand, you get a variety of withdrawal symptoms (13), including headaches, tiredness and irritability that means your neurotransmitter receptors have downregulated and it will take a few days for them to upregulate and bring you back to normal. For many just one cup of coffee a day can result in withdrawal effects if stopped (14). It’s also worth knowing that coffee, or caffeine, consumed 6 hours before sleep, which is about as long as caffeine stays in the system, is associated with disturbed sleep (15) – either difficulty falling asleep or waking in the night so, at least, it is wise to consume no caffeine after noon, especially if you have issues with sleeping.
Tea or coffee?
The caffeine in both coffee and tea increases the release of adrenalin, cortisol and dopamine in your body and brain, while inhibiting the absorption of adenosine, a brain-calming chemical. The release of adrenaline into your system gives you a temporary boost, but frequently makes you fatigued and depressed later. If you take more caffeine to counteract these effects, you end up spending the day in an agitated state, and might find yourself jumpy and edgy by night.
Tea contains caffeine, but also theanine, which has a more calming amino acid shown to enhance cognitive abilities (16). It also protects GABA receptors, which is the brain’s adrenalin off switch. Overall then, tea is better for you. Green tea may also have some benefits over black tea (the same plant, but processed differently such that green tea contains more antioxidants and polyphenols, which are good guys as far as our bodies are concerned).
Benefits or excuses?
Many things could be written on the apparent benefits of tea, coffee, even some forms of alcohol. We read about the beneficial effects of resveratrol in red wine, polyphenols in coffee and cacao and other antioxidants in tea. However, the nature of ANY dependence creates a psychological set of ‘excuses’ that we use to justify our addictive behaviour.
This could be anything from ‘that’s a lovely sauce’ (sugar), ‘a little bit of what you fancy won’t harm you’ ‘I’m so stressed I have to have a drink’, ‘I’ve got to focus so I need a coffee’ and so on. Of course, all these substances work, otherwise we wouldn’t be attracted to them and, in that sense, mindful consumption in certain circumstances makes sense. For example, if someone experiences a shock, a sugary drink can help. And when a deadline looms and you need to burn the candle at both ends, caffeine can certainly help.
The issue here is to understand how the combination of sugar, caffeinated stimulants, alcohol, tech and social media addiction, shopping, gambling, gaming and so on can hijack your brain’s natural reward system and result in the opposite – you feeling more tired, anxious, unfulfilled and depressed. If that’s happened to you, rest assured there are some simple suggestions that will help you reclaim your brain’s full potential for feeling good, energised, clear, focussed and purposeful.
Simple ways to win back your brain
Limit your time spent on social media – 30 minutes a day max is a good target but you may need to build down to this. Turn your phone off (or to ‘airplane’ mode) at least an hour before bed and keep it that way for at least an hour in the morning. If you have to have it on, don’t check social media for a couple of hours.
Limit your intake of caffeine to under 100 grams a day – that’s one strong cup of coffee or two weaker cups of tea. If you have a second cup, use the same tea bag, or have a filter coffee ‘run through’. Avoid all caffeine after noon.
Avoid buying food that contains added sugar, dates or raisins – if in doubt, read the label and remember sugar is often disguised as high fructose corn syrup. When looking at food labels remember 5g is a teaspoon of sugar and foods with more than 22.5g per 100g of sugar are considered high sugar and those with 5g or less per 100g are considered low sugar. Ideally, only have sugar in whole fresh fruits. Fruit juice is also high in sugar so best avoided or limited.
Limit your daily intake of alcohol to 20 grams, or a maximum of two small glasses (125ml is one small glass) of wine. Have at least two days a week alcohol-free.
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Food for the Brain is a non-for-profit educational and research charity that offers a freeCognitive Function Testand assesses your Dementia Risk Index to be able to advise you on how to dementia-proof your diet and lifestyle.
By completing theCognitive Function Testyou 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.
1 P. Holford, How to Quit Without Feeling S**t, Piatkus, 2008.
2 P. Holford, How to Quit Without Feeling S**t, Piatkus, 2008.
3 P.M. Johnson and P.J. Kenny ‘Dopamine D2 receptors in addiction-like reward dysfunction and compulsive eating in obese rats’, Nature Neuroscience (2010), vol. 13(5), pp. 635-641.
6 N.M. Avena and M.S. Gold, ‘Food Addiction – Sugars, Fats and Hedonic Eating’, Addiction (2011), vol. 106(7), pp. 1214-1215.
7 B. Lennerz et al., ‘Effects of dietary glycemic index on brain regions related to reward and craving in men’ The American Journal of Clinical Nutrition, Volume 98, Issue 3, 1 September 2013, Pages 641–647
14 Juliano LM, Griffiths RR. A critical review of caffeine withdrawal: empirical validation of symptoms and signs, incidence, severity, and associated features. Psychopharmacology (Berl). 2004 Oct;176(1):1-29. doi: 10.1007/s00213-004-2000-x. Epub 2004 Sep 21. PMID: 15448977.
15 Drake C, Roehrs T, Shambroom J, Roth T. Caffeine effects on sleep taken 0, 3, or 6 hours before going to bed. J Clin Sleep Med. 2013 Nov 15;9(11):1195-200. doi: 10.5664/jcsm.3170. PMID: 24235903; PMCID: PMC3805807.
16 Anas Sohail A, Ortiz F, Varghese T, Fabara SP, Batth AS, Sandesara DP, Sabir A, Khurana M, Datta S, Patel UK. The Cognitive-Enhancing Outcomes of Caffeine and L-theanine: A Systematic Review. Cureus. 2021 Dec 30;13(12):e20828. doi: 10.7759/cureus.20828. PMID: 35111479; PMCID: PMC8794723.
Our brains have a dual fuel mechanism. The brains of large-brained animals like us can run on either glucose or ketones, derived from fat. If given the choice they prefer ketones. The rise in popularity in high fat ketogenic diets is partly to do with the ability of ketones to nourish and improve brain function when things go wrong, as well as weight loss benefits and the potential to reverse diabetes.
Epilepsy, for example, has been successfully treated in both children and adults with a high-fat ketogenic diet since the 1920’s often halving the frequency of fits. A recent study on people with Parkinson’s found that those placed on a high-fat diet had 41 per cent reduction in shaking, compared to 11 percent on a low-fat diet. There’s also a potential benefit in chronic fatigue syndrome.
The reason these high-fat keto diets work is that if a cell’s sugar metabolism is all messed up, a consequence of insulin resistance promoted by a high-sugar diet, then the cell struggles to get enough energy and you feel mentally and physically tired. But if, like a hybrid car, you can switch to a different fuel, ketones, then the cell comes back to life. This is especially true in struggling brain cells. When you fast, and switch to burning your body fat, the brain derives two-thirds of its energy from ketones.
Ketones are made from medium-chain triglycerides, known as MCTs. The rise in sales of MCT oil, which can be derived from palm or coconut oil. Also gaining in popularity are ketone salts and pure synthetic ketones, although these are yet to clear EU Novel Foods so are not yet available in Europe.
Fats are chains of carbon molecules and MCTs contain C6, C8, C10 and C12 oil. Of these C8 oil (called tricaprylin or caprylic acid triglyceride) makes ketones fastest. While coconut oil is 60 percent MCTs only 12 percent of MCTs is C8. That means that only 7 percent of coconut oil is C8.
The growth in bullet-proof coffee, adding a blob of coconut oil to your morning brew, is one way to up ketone levels but it’s much less effective than adding pure C8 oil. Patrick Holford’s Hybrid Latté – a coffee with carb-free almond milk, almond butter, C8 oil, cacao and cinnamon, is a step up. While coffee gives you energy like a bank loan gives you wealth it does speed up conversion to running on ketones.
Case studies with coconut oil have shown short-term beneficial effects in people with Alzheimer’s, with improved mental clarity. Two breakthrough studies in Canada, by Dr Melanie Fortier and Professor Stephen Cunnane from Sherbrooke University in Canada have established that C8 oil can be extremely helpful as an energy source for those with cognitive decline. Cunnane is an expert on fatty acid metabolism in the brain who has held the ‘Canada Research Chair on Dietary Fatty Acids and Cognitive Function during Ageing’.
Are there any downsides? A few people report abdominal or stomach discomfort. This can be minimized by building up slowly – starting with a teaspoon, then a dessert spoon, then a tablespoon, then two, then three tablespoons taken at different times of day, with food or in drinks or neat.
If glucose is petrol ketones are electricity. If your brain needs a service, switching from running on carbs to running on ketones by eating a low-carb, high-fat diet for a week, may be a good idea. It takes only 12 hours to start to run out of glucose fuel and start switching to ketones. Also good is an 18-hour carb fast – eg dinner at 6pm, lunch at 1pm. My brain stays sharp and I don’t feel hungry.
Robert Lustig is Professor Emeritus of Pediatrics in the Division of Endocrinology, and Member of the Institute for Health Policy Studies at the University of California, San Francisco. He is a pediatric neuroendocrinologist,and an international authority on obesity, diabetes,nutrition,and neuroscience. He is the author of three books that have changed our understanding of the danger of sugar on our metabolism – Fat Chance, The Hacking of the American Mind, and Metabolical.
Most people know that refined sugar is not good for you, but what is it about sugar that’s particularly bad for your brain? Why is it essential, not only for brain health and dementia prevention, to reduce your intake of not only sugar but refined carbohydrates in general? (By refined, I mean those whose fiber has been processed away – not ‘whole’ as in vegetables, whole fruit (not juice), beans, and whole grains.
Let’s start at the extreme. What happens if you lived at the North Pole, and ate virtually no carbohydrates, or at least so little as to force your body and brain to switch to a kind of fuel, ketones, produced from fat? This is often called a “very low carb high fat” (LCHF) or “ketogenic” diet. Would you get sick? This is what Vilhjamur Steffanson did, when his Arctic exploration shipwrecked in 1913, and he was forced to live amongst the Inuit for two years. He noted that there was no diabetes, no cancer — and no Alzheimer’s. In 1928, he and his colleague checked themselves into Bellvue hospital, and ate only meat for one year.[1]They were healthier than the researchers who studied them!
Your brain likes ketones
Ketones are made in the liver from fat – either breaking down your own fat (for example, if you were fasting, eating very little or exercising a lot), or from ingestion of a type of fat containing ‘medium chain triglycerides’ (MCTs). Coconut oil is approximately 54% MCTs and contains all 4 MCTs (C6, C8, C10, C12), but it turns out that one particular kind of MCT, called C8 because it is 8 carbons long, is the best fat for the liver to convert into ketones.
You may be surprised to know that your brain can run well on glucose (the kind of sugar that is fuel for our cells), but even better on ketones. The reason is that ketones cross into the brain easily, rapidly, and without a biochemical transporter. This is why children with severe epilepsy improve on a ketogenic diet. Watch this short film ‘Fuel your Brain’.
Brain benefits of a low-carb ketogenic diet
In fact, brain cells prefer ketones. In two studies, one on people with Alzheimer’s and the other on those with pre-dementia or mild cognitive impairment, giving 2 tablespoons of C8 oil (called capricin or caprylic acid triglyceride), brain energy derived from ketones went up by 230% and memory and mental acuity improved in those with Minimal Cognitive Impairment (MCI).[2,3]
A ketogenic diet has been shown to reduce schizophrenia symptoms, help reduce shaking in Parkinson’s, and slow down cognitive decline in those with dementia or pre-dementia. In fact, the ketogenic diet has been used to effectively treat childhood epilepsy for over 100 years! There’s a good review on the current status of the ketogenic diet in psychiatry here.[4]
Ketogenic diets may help in many ways. Firstly, when a person eats too much carbohydrate, sugar, but especially fructose, damages the energy burning factories in cells, called mitochondria, so their ability to produce chemical energy for the neuron is greatly reduced. Switching to burning ketones instead can increase mitochondria number and function. A recent study also shows that a ketogenic diet has a positive effect on the gut microbiome,[5] and this might be one way the diet helps reduce fits in people with epilepsy.[6] Fructose, on the other hand, disrupts the gut microbiome in a negative way.
How sugar damages your brain
But what is it about a ketogenic diet that is good for your brain? Is it the ketones, the lowering of insulin, the type of fat, the elimination of carbohydrate, or specifically the elimination of sugar? We don’t yet know – I ask this question of every Alzheimer’s and metabolic researcher I know, and no one can tell me – just that it works.
There are a few possible mechanisms. First, the more carbs and sugar you eat, the more resistant you become to the hormone insulin. Insulin not only drives glucose into cells (including brain cells), but also sends excess sugar to the liver to turn into fat. When a person becomes insulin resistant, ironically, glucose transport is negatively impacted, reducing brain energy availability. Insulin resistance is a major driver of depression.[7] A ketogenic diet can reverse that.
Fructose, which comprises half of sucrose (‘white’ or ‘table’ sugar), and half of ‘high-fructose corn syrup’ (added to numerous processed foods), damages our mitochondria, which leads to less brain energy availability. One study showed that fructose reduces liver mitochondrial function, while glucose stimulates it.[8]“The most important takeaway of this study is that high fructose in the diet is bad,” said Dr. C. Ronald Kahn from the Joslin Diabetes Center. “It’s not bad because it’s more calories, but because it has effects on liver metabolism to make it worse at burning fat. As a result, adding fructose to the diet makes the liver store more fat, and this is bad for the liver and bad for whole body metabolism.”
Fructose is the main sugar in most fruits. People then extrapolate, “oh fruit must be bad for you.” Not true. Whole fruit has fibre (both soluble and insoluble); together they slow down glucose and fructose absorption in the GI tract limiting both liver and brain exposure, and they also help feed the gut bacteria (microbiome), so actually you get less fructose entering the bloodstream. Juicing the fruit removes the protective fiber, and juice has been shown to be just as dangerous to metabolism as is soda. So, eat your fruit — don’t drink it!
Carbohydrates and fructose age your brain
There’s another reason why sugar, and especially fructose, is bad for your brain and body. They produce Advanced Glycation Endpoints or AGEs, which damage the brain. These ‘oxidise’ proteins (so does cigarette smoke), rendering them useless , allowing them to aggregate into clumps, and use up valuable antioxidants in your diet such as vitamin C and E.
Fructose acts on your liver to switch your metabolism away from fat burning to fat making and storing, and inhibits an anti-ageing process called ‘autophagy’ which helps clean up and remove damaged mitochondria in order to regenerate new, healthier cells.
Why sweet foods are so addictive
So far we’ve only explored why sugar is bad for your “physical” brain. Knowing this is a good start. But why does your “emotional” brain keep telling you that you want it? Why do people find it so hard to resist, and so many become sugar addicts? The answer is that fructose activates the “reward system” in the brain. It causes dopamine release, the motivational neurotransmitter associated with ‘reward’. Any chemical that does so can be addictive – cocaine, heroin, alcohol, nicotine, or example. The trouble is the more you have, the more your brain ‘down-regulates’, i.e. becomes less responsive to your own natural feel-good dopamine, so you end up needing more sugar to get the hit and, in the end, you get no hit at all but feel thoroughly awful without it. That’s the Law of Diminishing Returns. That’s addiction.
Blood sugar control reduces dementia risk
Keeping blood glucose levels in the low-normal range is reflected by a low blood glycosylated haemoglobin (HbA1C) level, which means ‘sugar-coated red blood cells’. A low HbA1c is good and is a proxy for improved insulin sensitivity, associated with reduced risk for dementia in several studies.[9,10,11,12,13,14]
A new study also shows that, in 40 year old adults with so-called normal glucose levels but at the higher end of the normal range, have increased their risk of Alzheimer’s by 15% [37]
Type 2 diabetes, the net result of losing blood sugar control, almost doubles the risk for dementia.[15,16] Diabetes is also associated with more rapid brain shrinkage.[17,18] Even people in the upper normal range of blood glucose have increased brain atrophy, impaired cognition, and increased risk of dementia.[19,20]
For instance, one trial measured HbA1c and glucose levels in several thousand elderly people over the course of almost seven years.In that time, slightly more than a quarter of the participants developed dementia, and the bottom line was that rising glucose levels were associated with increased risk of developing the condition, irrespective of whether the participants also had diabetes. Non-diabetics who experienced a modest increase in blood sugar levels had an 18% increased risk of dementia, as compared to those who already had diabetes at the start of the study or developed it within the trial period, who had a 40% increased risk.[21]
Insulin resistance is strongly related to cognitive decline
But even more important than loss of glucose control is the loss of insulin control. Back in 2004, researchers at Columbia University showed that people with high insulin levels – the principal hallmark of metabolic dysfunction – were twice as likely to develop dementia as those with healthy levels. Moreover, those with the highest insulin levels had the worst memory retrieval.[22] The same year, an Italian study established a link between heightened insulin levels and declining mental function.[23] Similarly, a Puerto Rican study found that people who consumed the large amounts of sugar doubled their risk of suffering poor cognitive function,[24] while another US study discovered a strong correlation between blood sugar level and memory loss.[25]
Two studies – one in Ireland,[26] and the other in the United States,[27] – established a link between high dietary glycemic load (GL; how high does your blood glucose rise when you eat carbohydrate) and cognitive decline. Indeed, both of these reports suggested that high GL is even more predictive of the pathological changes associated with Alzheimer’s than either high carb or high sugar intake. A high GL diet is also associated with more amyloid plaque[28] and more cognitive decline, especially in those who carry the ApoE4 gene, a regulator of fat metabolism.[29]
A long-term study found evidence that this sort of shrinkage is more common among people with high blood glucose levels, even when those levels are still within what are considered ‘normal’ (i.e. non-diabetic) limits.[30] This cognitive decline starts young. Cognitive decline in overweight children is associated with a high GL diet[31], and adolescents with metabolic dysfunction driven by a high GL diet have been shown to have shrinkage of the hippocampal area of the brain, as well as other structural changes and cognitive deficits. [32,33]
Prevention action – how to cut down your sugar load
In practical terms, preventing dementia today means avoiding sugar as much as possible. If you’re going to eat carbohydrate, eat ‘whole’ carbohydrate foods such as whole vegetables, fruits (not juice), beans, only wholegrain bread (labelled as ‘100% wholegrain’, or pasta in small quantities.
Starchy carbohydrates such as pasta, rice and potatoes benefit from being cooked and cooled, then eaten cold or re-heated, as some of the carbohydrate is converted into resistant starch – a type of fibre we can’t digest but which has the added benefit of fermenting and feeding our gut bacteria.
Make sure the carbohydrate comes with its inherent fibre. Oat cakes would be better than bread since the fibre in these foods helps ‘slow release’ the sugars. Eating white bread is associated with a poorer cognitive test performance, whereas high fibre bread is associated with better performance.[34] Eating carbohydrate foods with protein, for example brown rice with fish, or porridge oats with seeds, or fruit with nuts, further reduces the glycemic load (GL) of a meal. The best fruits in this respect are low-sugar high-fiber fruits like berries, cherries, and plums.
These kinds of foods are consistent with a Mediterranean diet which has also been shown to reduce risk.[35] Conversely, grapes, raisins, and bananas are high GL. A study in Finland and Sweden compared those with a healthy versus unhealthy diet, including the above criteria, in mid-life for future risk of developing Alzheimer’s disease and dementia 14 years later. Those who ate the healthiest diet had an 88% decreased risk of developing dementia and a 92% decreased risk of developing Alzheimer’s disease.[36]
The take-home message is, if you are going to eat complex carbohydrates, eat them with fibre, fat and protein.
However, if you want to go one step further, you can switch to eating a ketogenic low-carb, high fat diet. The problem with the ketogenic diet is staying on it – there’s so much carbohydrate out there it’s hard to avoid it. But there are now breath monitors (e.g. Ketoscan, BioSense from ReadOut Health) that can help you stay in ketosis. A good book to help you explore and put into practice either a low carb ketogenic diet or a low GL diet is ‘The Hybrid Diet’ by Patrick Holford & Jerome Burne. And to understand how processed food is your enemy, take a look at my book ‘Metabolical’.
And if you want to know how sugar is impacting your body and brain then you can take one of our at-home, pin-prick, DRIfT blood test so you can know exactly how sugar is impacting your body and also become a part of our vital research into this area.
Food for the Brain is a non-for-profit educational and research charity that offers a freeCognitive Function Testand assesses your Dementia Risk Index to be able to advise you on how to dementia-proof your diet and lifestyle.
By completing theCognitive Function Testyou 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
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