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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).

Your Glutathione Index Defines How Your Cells Are Ageing

Nutritional therapists have been measuring red cell glutathione and supplementing glutathione or its precursor N-Acetyl-Cysteine (NAC) for decades. But it’s really hard, and expensive, to measure accurately. Until now.

So how does the Glutathione Index work? 

All of life is a balance between antioxidants and oxidants. That is why we, an oxygen based lifeform, have a finite life. Inside your cells glutathione (GSH) is working every second to stop harmful oxidants from ageing you. The result is spent or oxidised glutathione (GSSG). Our new test – a world first – measures the ratio between fully loaded glutathione (GSH) and oxidised glutathione (GSSG). The Glutathione index (GSH/GSSG) shows you how much antioxidant potential you have and how many metabolic fires you’ve extinguished. This ratio is the difference between mental health and mental illness.

Why does knowing this single marker help with Alzheimer’s, diabetes, schizophrenia, severe autism, depression & more?

Why Does Knowing This Single Marker Help With Alzheimer’s, Diabetes, Schizophrenia, Severe Autism, Depression and More?

The Science

NAC has plenty of evidence to support its use as a promoter of glutathione and mental health, thus reducing the brain’s oxidative stress. The latest 2022 review states:

“N-acetyl-L-cysteine (NAC) is a compound of increasing interest in the treatment of psychiatric disorders. Primarily through its antioxidant, anti-inflammatory, and glutamate modulation activity, NAC has been investigated in the treatment of neurodevelopmental disorders, schizophrenia spectrum disorders, bipolar-related disorders, depressive disorders, anxiety disorders, obsessive compulsive-related disorders, substance-use disorders, neurocognitive disorders, and chronic pain. Currently NAC has the most evidence of having a beneficial effect as an adjuvant agent in the negative symptoms of schizophrenia, severe autism, depression, and obsessive compulsive and related disorders.” (1)

Glutathione and Schizophrenia

Quoting Lorraine Wilder (whose MSc in schizophrenia we funded) “Glutathione (GSH) is an important antioxidant and free radical scavenger that has been found to be decreased in the brains of people with schizophrenia [2, 3]. Although oral GSH supplementation has poor bioavailability [4], N-Acetyl Cysteine (NAC) has been shown to successfully raise plasma glutathione levels in those with schizophrenia [5]”.

Clinical Evidence and Case Studies

In a case study of a 24 year old woman with chronic and worsening paranoid-type schizophrenia that was generally unresponsive to anti-psychotic treatment, the addition of NAC supplementation improved the patient’s symptomatology in seven days. In addition to the schizophrenia-specific symptoms, improvements were observed in spontaneity, social skills and family relations by both the patient and family members. A randomised placebo-controlled trial (RCT) including 42 participants with schizophrenia, who were experiencing an acute phase of symptomatology, were randomly assigned to receive up to 2 g/d of NAC plus up to 6 mg/d of risperidone for 8 weeks as an adjunct intervention. Significant negative symptoms were found in the active treatment group compared to controls but not in positive or general psychopathology [6].

Larger Trials and Longer-Term Findings

Furthermore, a larger RCT of 140 participants observed significant improvements on global symptomatology and general and negative symptoms of schizophrenia in the NAC supplementation (2 g/d; in addition to anti-psychotic medication) group in comparison to the placebo group over a 24-week period, but not positive symptoms [7]. Notably, after a 4-week washout period these beneficial effects diminished, with the exception of clinical severity scores. 

Expert Perspective on Brain Oxidative Stress

According to Dr Chris Palmer, assistant professor at HarvaWhy the Glutathione Index Is the Best Indicator of Brain Oxidative Stress
rd Medical School:

“Glutathione (GSH), the brain’s primary antioxidant, plays a crucial role in maintaining redox balance. Magnetic resonance studies have provided mixed results regarding GSH levels in schizophrenia patients, with some studies indicating decreased levels in chronic schizophrenia, while others found no significant differences. However, these inconsistencies may be due to variations in disease chronicity, age, and symptom severity among study participants. The findings from these studies suggest several potential therapeutic targets for schizophrenia. Addressing mitochondrial dysfunction, redox imbalance, and impaired energy metabolism could lead to more effective treatments. For instance, N-acetylcysteine (NAC), a precursor to GSH, has shown promise in increasing brain GSH levels and improving symptoms in first episode psychosis patients.”

Why the Glutathione Index Is the Best Indicator of Brain Oxidative Stress

The GSH/GSSG ratio reflects the activity of the enzyme glutathione reductase which is responsible for the transformation of GSSG (used, oxidised) to GSH (the reduced or fully loaded form that acts as a radical scavenger). 

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Glutathione Reductase and Dementia

Reductions in glutathione reductase (GR) enzyme levels in patients with dementia are well established. GR levels alone are therefore a fairly good biomarker of dementia. But the mere presence of the enzyme does not guarantee its high activity. GR needs to consume NADP molecules to function properly. The advantage of our test is, therefore, that it shows changes in GR activity not only due to higher/lower GR gene activity but also due to the absence of the reaction cofactor NADP. 

Impaired Glutathione Recycling in Dementia

As shown by Irene Martinez de Toda et al 2019 (8) data, patients with dementia have a reduction in both the enzymes (GR and GP) that recycle glutathione. Thus, in general, it can be said that the glutathione metabolism (recycling) loop in those with dementia ‘spins’ much slower than in healthy patients. As a result, dementia patients have a lower potential to dynamically fight free radicals and will have a worse Glutathione Index.

What Happens When Recycling Slows Down

In patients, the enzyme GR, which is responsible for recycling spent/oxidised glutathione back to fully loaded, slows down, which leads to the accumulation of oxidised glutathione (GSSG) and the depletion and inability to produce GSH. 

Thus, the concentration of GSH decreases while that of GSSG increases. Hence the Glutathione Index gets worse / is lower.

Improving your Glutathione Index

The older a person is the lower their Glutathione Index is likely to be (see figure below)

Improving your Glutathione index is important as higher levels predict better cognitive function according to our preliminary research. (see figure).

Our own laboratory’s study of 8 people given a supplement containing lipoid acid and N-acetyl-Cysteine (NAC) supplements, the precursor for glutathione, show improvement in both the Glutathione Index and Glutazthione. (see figure below)

Studies giving Ubiquinol, the active form of CoQ, also show an improvement in both the Glutathione Index

Developing the Glutathione Index Test

So will you join us and become a part of our Anti-Age Your Brain Campaign? We need Citizen Scientists to order and complete the test so you can start to protect your brain from ageing and so we can research what the ‘perfect number’ is.

Order your Glutathione test here

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.

References

1. Bradlow RCJ, Berk M, Kalivas PW, Back SE, Kanaan RA. The Potential of N-Acetyl-L-Cysteine (NAC) in the Treatment of Psychiatric Disorders. CNS Drugs. 2022 May;36(5):451-482. doi: 10.1007/s40263-022-00907-3. Epub 2022 Mar 22. Erratum in: CNS Drugs. 2022 Apr 28;: PMID: 35316513; PMCID: PMC9095537.

2 Yao JK, Leonard S, Reddy R: Altered glutathione redox state in schizophrenia. Dis Markers 2006, 22(1):83–93.

3 Gawryluk JW, Wang J-F, Andreazza AC, Shao L, Young LT: Decreased levels of glutathione, the major brain antioxidant, in post-mortem prefrontal cortex from patients with psychiatric disorders. Int J Neuropsychopharmacol 2011, 14(01):123–130.

4  Witschi A, Reddy S, Stofer B, Lauterburg B: The systemic availability of oral glutathione. Eur J Clin Pharmacol 1992, 43(6):667–669.

5. Lavoie S, Murray MM, Deppen P, Knyazeva MG, Berk M, Boulat O, Bovet P, Bush AI, Conus P, Copolov D, Fornari E, Meuli R, Solida A, Vianin P, Cuénod M, Buclin T, Do KQ:Glutathione precursor, N-acetyl-cysteine, improves mismatch negativity in schizophrenia patients. Neuropsychopharmacology 2008, 33(9):2187–2199.

6. Farokhnia M, Azarkolah A, Adinehfar F, Khodaie-Ardakani M-R, Hosseini S-M-R, Yekehtaz H, Tabrizi M, Rezaei F, Salehi B, Sadeghi S-M-H, Moghadam M, Gharibi F, Mirshafiee O:, Akhondzadeh S: N-acetylcysteine as an adjunct to risperidone for treatment of negative symptoms in patients with chronic schizophrenia: a randomized, double-blind, placebo-controlled study. Clin Neuropharmacol 2013, 36(6):185–192.

7. Berk M, Copolov D, Dean O, Lu K, Jeavons S, Schapkaitz I, Anderson-Hunt M, Judd F, Katz F, Katz P, Ording-Jespersen S, Little J, Conus P, Cuenod M, Do KQ, Busha AI: N-acetyl cysteine as a glutathione precursor for schizophrenia—a double-blind, randomized, placebo-controlled trial. Biol Psychiatry 2008, 64(5):361–368.

8. Martínez de Toda I, Vida C, Sanz San Miguel L, De la Fuente M. Function, Oxidative, and Inflammatory Stress Parameters in Immune Cells as Predictive Markers of Lifespan throughout Aging. Oxid Med Cell Longev. 2019 Jun 2;2019:4574276. doi: 10.1155/2019/4574276. PMID: 31281577; PMCID: PMC6589234.

9.Tian G, Sawashita J, Kubo H, Nishio SY, Hashimoto S, Suzuki N, Yoshimura H, Tsuruoka M, Wang Y, Liu Y, Luo H, Xu Z, Mori M, Kitano M, Hosoe K, Takeda T, Usami S, Higuchi K. Ubiquinol-10 supplementation activates mitochondria functions to decelerate senescence in senescence-accelerated mice. Antioxid Redox Signal. 2014 Jun 1;20(16):2606-20. doi: 10.1089/ars.2013.5406. Epub 2013 Dec 14. PMID: 24124769; PMCID: PMC4025630.] and glutathione in people with metabolic syndrome

10.Raygan F, Rezavandi Z, Dadkhah Tehrani S, Farrokhian A, Asemi Z. The effects of coenzyme Q10 administration on glucose homeostasis parameters, lipid profiles, biomarkers of inflammation and oxidative stress in patients with metabolic syndrome. Eur J Nutr. 2016 Dec;55(8):2357-2364. doi: 10.1007/s00394-015-1042-7. Epub 2015 Sep 18. PMID: 26385228.)

By Patrick Holford

Read part one here to learn about the first two ‘horsemen’ – Brain Fats & Methylation.

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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.

(Click here to test your HbA1c and be a part of our Citizen Science Research)

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Do ketones fill the energy gap?

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.

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Want to learn more about homocysteine and how to reclaim your brain? Join us for the Homocysteine Unplugged webinar.

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.

References

1 Lakhan, S.E., Kirchgessner, A. The emerging role of dietary fructose in obesity and cognitive decline. Nutr J 12, 114 (2013). 

2 https://www.psychiatrist.com/news/a-19-year-old-is-youngest-ever-to-be-diagnosed-with-alzheimers/

3 Yau PL, Castro MG, Tagani A, Tsui WH, Convit A. Obesity and metabolic syndrome and functional and structural brain impairments in adolescence. 

Pediatrics. 2012 Oct;130(4):e856-64. doi: 10.1542/peds.2012-0324. Epub 2012 Sep 

4  Zhang X, et al Midlife lipid and glucose levels are associated with Alzheimer’s disease. Alzheimers Dement. 2023

5  Fortier M, Castellano CA, St-Pierre V, Myette-Côté É, Langlois F, Roy M, Morin MC, Bocti C, Fulop T, Godin JP, Delannoy C, Cuenoud B, Cunnane SC. A ketogenic drink improves cognition in mild cognitive impairment: Results of a 6-month RCT. Alzheimers Dement. 2021 Mar;17(3):543-552. doi: 10.1002/alz.12206. Epub 2020 Oct 26. PMID: 33103819; PMCID: PMC8048678.

6 Crawford, M.A..; Sinclair, A.J.; Wang, Y.;
Schmidt, W.F.; Broadhurst, C.L.; Dyall, S.C.; Horn, L.; Brenna, J.T.; Johnson, M.R.; Docosahexaenoic Acid Explains the Unexplained in Visual Transduction. Entropy 2023, 25, x. https://doi.org/10.3390/xxxxx 

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.

By Patrick Holford

Did you know the length of your shadow can tell you if you’re able to generate vitamin D from sunlight?

If your shadow is longer than your body – you can’t produce vitamin D from sunlight. If you are in winter and live in a country of higher latitude (like the UK), this is happening now!

Vitamin D is an all-rounder as far as your brain and mental health is concerned.

It helps neurotransmission and exerts anti-inflammatory and neuroprotective activities within the brain by reducing both inflammation and oxidative stress (1).  

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We are all deficient in winter

Generally speaking, the lower your vitamin D, the worse your mood which makes vitamin D especially important to supplement from October to March if you live in the UK or a similar latitude, when the angle of the sun is too low and you’re also less likely to get outdoors exposing your skin to sunlight. It’s best to assume that we are all deficient in winter, unless you travel to the sun, and therefore need to supplement at least 25mcg (1000iu) although two or three times may be optimal and necessary to correct deficiency.

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Vitamin D and depression

The lower your vitamin D level, the more depressed you are likely to feel. If your mood takes a dip in winter months this is a key sign that you might need more. That’s what researchers at the University of Tromso in Norway found on testing 441 volunteers who were given a test for depression and also a test for blood levels of vitamin D. The volunteers were then given Vitamin D supplements or placebo. Tested one year on, those given vitamin D, but not those given the placebos, had substantially lower depression ratings (2).

However, you don’t have to wait for a year to get a lift in your mood. An eight-week study in Australia found that some of those given vitamin D supplements had an improvement in mood in only five days (3). Another study, in Iran, gave a single vitamin D injection and reported improvement in depression when measured 3 months on (4).

Since vitamin D stores, there is no need to supplement daily. You can take a weekly dose. In the Norwegian study above they gave 20,000iu or 40,000iu weekly. Both worked and there wasn’t a big difference in the effects on mood. So, you can assume that 20,000iu weekly, or 3,000iu daily would likely be sufficient.

It’s what is in your blood that matters

However, the yardstick for what you need is really whatever gets your blood level into the optimal range.

In the study above, those given 20,000iu a week averaged a blood level of 88 nmol/l, while those given 40,000iu averaged 111nmol/l. It is now well recognised that levels above 75nmol/l (30 ng/ml) correlate with good health for many health measures, while levels above 100nmol/l (40ng/ml) might be even better in some respects. My recommendation is to test yourself and consider anything below 50 to be deficient, and above 75 to be sufficient with an optimal level being closer to 100nmol/l (40ng/ml). If you then supplement 3,000iu daily, or seven times this weekly, especially from October to March, retest yourself against these yardsticks.

It’s not JUST about vitamin D

But it isn’t just vitamin D we need – it’s sunlight.

During the summer months, if you are spending half an hour outdoors, with short sleeves, shorts or even more skin exposure, in the sunlight, even a multivitamin that provides you 800iu (a quarter of what you need in the darker months) might be sufficient.

Sunlight promotes serotonin, the happy neurotransmitter.

Having good vitamin D levels is a vital part of your brain upgrade since it helps optimise your brain’s serotonin levels. That’s because a vital enzyme called TPH, which converts the amino acid tryptophan into serotonin, is enhanced in the brain by vitamin D, and selectively shut down in the gut. So, with sufficient vitamin D you get higher brain levels of serotonin, promoting good mood, and lower serotonin levels in the gut (5), protecting against gut inflammation. 

The other way to boost your light exposure is with light therapy. Canadian researchers compared the effects of an anti-depressant (fluoxetine), placebo or 30 minutes daily of light therapy as soon as possible on waking for people with major depression. Light therapy was both superior to placebo and anti-depressants, which were also no better than placebo. I have a full spectrum light in my study, which I put on in the winter, when I’m writing in the early morning, before the sun comes up.

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Vitamin D and addiction

Interestingly, vitamin D deficiency is also associated with greater opioid addiction (7), suggesting the need to up vitamin D intake to reduce cravings. There’s also something else interesting about vitamin D, sun exposure and addiction. People can become addicted to sunbeds. In relation to opioids, the lower one’s vitamin D levels, the more addictive they become. Sun exposure, which promotes higher vitamin D levels, reduces opioid addiction.

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What to eat?

The best food sources of vitamin D are oily fish and eggs. A serving of salmon or mackerel is likely to give you 400iu of vitamin D. Two eggs will provide about 130iu. In some countries, not the UK, milk is fortified with vitamin D but otherwise, it is not a great source. Some mushrooms are purposely fortified with vitamin D by exposing them to UV light.

In summary, the way up from down is to eat a low GL diet, with plenty of oily fish and eggs, avoid sugar, cut back on stimulants and alcohol, and make sure your daily supplements include omega-3, B vitamins, with extra B12 if your homocysteine level is high, vitamin D, zinc, magnesium, chromium, plus the amino acids 5-HTP with is the precursor of serotonin.

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Vitamin D protects your brain and memory.

Vitamin D deficiency increases the risk of Alzheimer’s (9). In a study in France involving 912 elderly patients followed for 12 years, a total of 177 dementia cases occurred. Those with low vitamin D levels had a nearly three-fold increased risk of Alzheimer’s (10). Supplementing 800iu (20mcg) a day for 12 months has also been shown to improve cognitive function (11). 

Supplements may also help ward off dementia, according to a recent, large-scale study involving over twelve thousand dementia-free 70+ year-olds in the US (12). More than a third (37%) took supplements of vitamin D. Those who did had a 40% lower incidence of dementia. Professor Zahinoor Ismail, of the University of Calgary and University of Exeter, who led the research, said: “We know that vitamin D has some effects in the brain that could have implications for reducing dementia, however so far, research has yielded conflicting results. Overall, we found evidence to suggest that earlier supplementation might be particularly beneficial, before the onset of cognitive decline.”

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Vitamin D helps recovery from strokes and brain injury

Having a higher vitamin D level or supplementing vitamin D at levels above 2,000iu a day also helps people recover from strokes (13) and other forms of brain injury.

I recommend 3,000iu a day or 21,000iu a week in winter but most importantly, monitoring your vitamin D level to keep it above 75nmol/l (30 ng/ml). A level of 100nmol/l may be optimal. That is why testing is so vital as winter approaches. Test again 3 months later so you know if you’re taking enough or too much and that will give you a good gauge as spring approaches when you can probably lower your intake to 600 to 1,000iu depending on sun exposure and diet to top up to over 1,000iu.

Vitamin D is vital in pregnancy and for children

A breastfeeding mother must, at least, supplement omega-3 fish oils and ensure enough B vitamins for homocysteine to be below 7 mcmol/L, but many other nutrients are also necessary. Low vitamin D status in both the mother and newborn baby increases the likelihood of developing autistic spectrum disorder by 54% (14).

Without sufficient nutrients not only do brain cells not make the connections but the production and flow of neurotransmitters doesn’t happen optimally. Bruce Ames, Emeritus professor of Biochemistry and Molecular Biology at the University of California, thinks that “serotonin synthesis, release, and function in the brain are modulated by vitamin D and the 2 marine omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).” He says that ”insufficient levels of vitamin D, EPA, or DHA, in combination with genetic factors and at key periods during development, would lead to dysfunctional serotonin activation and function and may be one underlying mechanism that contributes to neuropsychiatric disorders and depression in children”. (15) 

A study in Northern Ireland found that half of schoolchildren were deficient in vitamin D, with a level below 50nmol/l (I recommend above 75 nmol/l). Another finds that low vitamin D levels in childhood are related to behaviour problems in adolescence (16). Is it any wonder so many children are neurodivergent?

A placebo-controlled trial giving ADHD children magnesium together with vitamin D for eight weeks showed a major reduction in emotional, conduct and peer problems and improved socialisation compared with children treated with the placebo (17).

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The bottom line – we all need to supplement vitamin D

The bottom line is everyone, from children to older people, and especially anyone considering pregnancy, suffering with low mood or memory problems, must test their vitamin D, ideally, at the start of winter to guide them as to what to supplement, during winter perhaps at 3 months, and 6 months later, to learn what amount of vitamin D supplementation they need in summer and winter.

In summary, you want to get your blood level above 75nmol/l (30 ng/ml) which usually means supplementing 3,000iu from October to March for those in the Northern Hemisphere. The optimal level is, however,  likely to be above 100nmol/l (40mg/ml).  Your need for vitamin D is likely to be greater if you are overweight and have darker skin and live further North.

When spring returns, and throughout summer, 1,000iu a day may be enough depending on your sun exposure.

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.

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References

¹ Jayedi A, Rashidy-Pour A, Shab-Bidar S. Vitamin D status and risk of dementia and Alzheimer’s disease: A meta-analysis of dose-response †. Nutr Neurosci. 2019 Nov;22(11):750-759. doi: 10.1080/1028415X.2018.1436639. Epub 2018 Feb 15. PMID: 29447107

² Jorde R, Sneve M, Figenschau Y, Svartberg J, Waterloo K. Effects of vitamin D supplementation on symptoms of depression in overweight and obese subjects: randomized double blind trial. J Intern Med. 2008 Dec;264(6):599-609. doi: 10.1111/j.1365-2796.2008.02008.x. Epub 2008 Sep 10. PMID: 18793245.

³ Khoraminya N, Tehrani-Doost M, Jazayeri S, Hosseini A, Djazayery A. Therapeutic effects of vitamin D as adjunctive therapy to fluoxetine in patients with major depressive disorder. Aust N Z J Psychiatry. 2013 Mar;47(3):271-5. doi: 10.1177/0004867412465022. Epub 2012 Oct 23. PMID: 23093054. Xxxx check the some in 5 days

⁴ Mozaffari-Khosravi H, Nabizade L, Yassini-Ardakani SM, Hadinedoushan H, Barzegar K. The effect of 2 different single injections of high dose of vitamin D on improving the depression in depressed patients with vitamin D deficiency: a randomized clinical trial. J Clin Psychopharmacol. 2013 Jun;33(3):378-85. doi: 10.1097/JCP.0b013e31828f619a. PMID: 23609390.

⁵ Patrick RP, Ames BN. Vitamin D hormone regulates serotonin synthesis. Part 1: relevance for autism. FASEB J. 2014 Jun;28(6):2398-413. doi: 10.1096/fj.13-246546. Epub 2014 Feb 20. PMID: 24558199.

⁶ Lam RW, Levitt AJ, Levitan RD, Enns MW, Morehouse R, Michalak EE, Tam EM. The Can-SAD study: a randomized controlled trial of the effectiveness of light therapy and fluoxetine in patients with winter seasonal affective disorder. Am J Psychiatry. 2006 May;163(5):805-12. doi: 10.1176/ajp.2006.163.5.805. PMID: 16648320.Psychiary, No015

⁷ Kemény LV, Robinson KC, Hermann AL, Walker DM, Regan S, Yew YW, Lai YC, Theodosakis N, Rivera PD, Ding W, Yang L, Beyer T, Loh YE, Lo JA, van der Sande AAJ, Sarnie W, Kotler D, Hsiao JJ, Su MY, Kato S, Kotler J, Bilbo SD, Chopra V, Salomon MP, Shen S, Hoon DSB, Asgari MM, Wakeman SE, Nestler EJ, Fisher DE. Vitamin D deficiency exacerbates UV/endorphin and opioid addiction. Sci Adv. 2021 Jun 11;7(24):eabe4577. doi: 10.1126/sciadv.abe4577. PMID: 34117054; PMCID: PMC8195487.

⁸ Jayedi A, Rashidy-Pour A, Shab-Bidar S. Vitamin D status and risk of dementia and Alzheimer’s disease: A meta-analysis of dose-response †. Nutr Neurosci. 2019 Nov;22(11):750-759. doi: 10.1080/1028415X.2018.1436639. Epub 2018 Feb 15. PMID: 29447107

⁹ Chai B, Gao F, Wu R, Dong T, Gu C, Lin Q, Zhang Y. Vitamin D deficiency as a risk factor for dementia and Alzheimer’s disease: an updated meta-analysis. BMC Neurol. 2019 Nov 13;19(1):284. doi: 10.1186/s12883-019-1500-6. PMID: 31722673; PMCID: PMC6854782.

10 Jia J, Hu J, Huo X, Miao R, Zhang Y, Ma F. Effects of vitamin D supplementation on cognitive function and blood Aβ-related biomarkers in older adults with Alzheimer’s disease: a randomised, double-blind, placebo-controlled trial. J Neurol Neurosurg Psychiatry. 2019 Dec;90(12):1347-1352. doi: 10.1136/jnnp-2018-320199. Epub 2019 Jul 11. PMID: 31296588.

11 Feart C, Helmer C, Merle B, Herrmann FR, Annweiler C, Dartigues JF, Delcourt C, Samieri C. Associations of lower vitamin D concentrations with cognitive decline and long-term risk of dementia and Alzheimer’s disease in older adults. Alzheimers Dement. 2017 Nov;13(11):1207-1216. doi: 10.1016/j.jalz.2017.03.003. Epub 2017 May 16. PMID: 28522216.

12 Ghahremani M, Smith EE, Chen HY, Creese B, Goodarzi Z, Ismail Z. Vitamin D supplementation and incident dementia: Effects of sex, APOE, and baseline cognitive status. Alzheimers Dement (Amst). 2023 Mar 1;15(1):e12404. doi: 10.1002/dad2.12404. PMID: 36874594; PMCID: PMC9976297.

13 Marek K, Cichoń N, Saluk-Bijak J, Bijak M, Miller E. The Role of Vitamin D in Stroke Prevention and the Effects of Its Supplementation for Post-Stroke Rehabilitation: A Narrative Review. Nutrients. 2022 Jul 4;14(13):2761. doi: 10.3390/nu14132761. PMID: 35807941; PMCID: PMC9268813.

14 Wang Z, Ding R, Wang J. The Association between Vitamin D Status and Autism Spectrum Disorder (ASD): A Systematic Review and Meta-Analysis. Nutrients. 2020 Dec 29;13(1):86. doi: 10.3390/nu13010086. PMID: 33383952; PMCID: PMC7824115.

15 Patrick RP, Ames BN. Vitamin D and the omega-3 fatty acids control serotonin synthesis and action, part 2: relevance for ADHD, bipolar disorder, schizophrenia, and impulsive behavior. FASEB J. 2015 Jun;29(6):2207-22. doi: 10.1096/fj.14-268342. Epub 2015 Feb 24. PMID: 25713056.

16 Sonia L Robinson, Constanza Marín, Henry Oliveros, Mercedes Mora-Plazas, Betsy Lozoff, Eduardo Villamor, Vitamin D Deficiency in Middle Childhood Is Related to Behavior Problems in Adolescence, The Journal of Nutrition, Volume 150, Issue 1,

2020, Pages 140-148, ISSN 0022-3166, https://doi.org/10.1093/jn/nxz185.

17 Hemamy M, Pahlavani N, Amanollahi A, Islam SMS, McVicar J, Askari G, Malekahmadi M. The effect of vitamin D and magnesium supplementation on the mental health status of attention-deficit hyperactive children: a randomized controlled trial. BMC Pediatr. 2021 Apr 17;21(1):178. doi: 10.1186/s12887-021-02631-1. Erratum in: BMC Pediatr. 2021 May 12;21(1):230. PMID: 33865361; PMCID: PMC8052751.

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By Patrick Holford

Life is a balancing act between making energy by combusting glucose or ketones with oxygen, which generates ‘oxidant’ exhaust fumes and dealing with these ‘oxidant fumes’ which harm the body.

Skin goes crinkly, age spots develop all due to oxidation. That’s what makes apples go brown, leaves change colour and iron rust. In the end, we lose, which is why all oxygen-based life forms have a finite life – and why your brain and body do inevitably age.

However, you can not only add years to your life, but also life to your years by improving your intake of antioxidants and polyphenols found in whole foods, fruits, vegetables and herbs and spices. A study in Finland and Sweden compared those with a ‘healthy’ versus ‘unhealthy’ diet in mid-life for future risk of developing Alzheimer’s disease and dementia 14 years later (1). Those who ate the healthiest diet had an 86-90% decreased risk of developing dementia and a 90-92% decreased risk of developing Alzheimer’s disease. Some of the benefit comes from low sugar diets, high in omega-3 and B vitamins and some from foods high in antioxidants and polyphenols which we will focus on here.

Your intake of these versus your intake and generation of oxidants, for example from smoking and pollution, is a major determinant of brain health. An illustration of this is the fact that both smoking and pollution exposure increase risk of cognitive decline and dementia, while vitamin C, which is the antioxidant par excellence, reduces risk.

(This is why we have developed our brand new Glutathione at home blood test – the first of its kind where you can accurately test your antioxidant status from home and support our further research into this important area. You can find out more and pre order the test here )

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Oxidants vs antioxidants – moving the balance in your favour

Smoking increases risk of Alzheimer’s just as much as having low B vitamin or omega-3 status, according to the US National Institute of health’s analysis (2). Smoking is something a person can easily change. Air pollution, for many, is not. It is measured in the amount of particulate matter (PMs) and people living in polluted cities are exposed to more. A study of women living in cities in the US found that those exceeding the ‘safe’ levels (greater than 12 μg/m3) had ‘increased the risks for global cognitive decline and all-cause dementia respectively by 81% and 92%’. (3)

While you may not be able to change where you live, can you mitigate the effects of pollution? The answer is yes – in two ways. Firstly, by increasing your intake of antioxidants and also by improving your B vitamin status since the body detoxifies many toxins, including toxic metals from lead to mercury, by methylation. A similar study to the one above found that residing in locations with PM exposure above the safe level was associated with a higher risk of dementia but only among people with lower intakes of the homocysteine lowering B vitamins (B6, folate, b12) (4). ‘Vitamin C in the diet or taken as supplements might help’ concludes another.(5)

Smokers need at least twice as much vitamin C as non-smokers just to have basic vitamin C levels in their blood (serum). Men do worse than women. Even with an intake of 200mg a day they do not achieve this basic blood level, which is already two to three times the recommended dietary intake and what you’d get in four oranges (6). It is certainly wise for any smoker to supplement vitamin C, perhaps adding 50mg per cigarette – 500mg if you smoke 10 a day, although there is a good case for everyone to supplement 1,000mg a day, or 2,000mg a day if over 50.

Nature always provides a solution to help us with our evolution. It seems obvious to me we need vitamin C to combat excessive pollution.

Vitamin C is a keystone nutrient as far as swinging the antioxidant equation in your favour. It’s made in all living things, from animals to plants, including yeasts and funghi. It’s probably been the essential ‘exhaust recycler’ of all oxygen-based lifeforms. Production is even activated when oxidants are sensed. Animals also make more when stressed or exposed to viruses. Us humans, and all other primates, are one of very few species who can’t make it. The first non-vitamin C making animal to be discovered was the guinea pig. That’s how it became the ‘guinea pig’ for research since, like us, it’s dependent every second of every day on vitamin C from diet. Bats, a few birds and the teleost family of fish have also lost the ability to make vitamin C. 

You’ll see in this figure below and from watching the film above, that vitamin C disarms water-based oxidants, such as smoke, and vitamin E disarms fat-based oxidants such as burnt fat. Then, there are other key antioxidant team players that help to neutralise the reactive oxidants that damage our brain and body.

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Your best bet is probably to both eat a diet with a broad spectrum of antioxidants and also supplement them. The older you are the more you are likely to need. Key antioxidants are:

Vitamin A, C and E – associated with reducing Alzheimer’s risk
Lipoic acid (7) – protects the memory-friendly neurotransmitter acetylcholine and dampens down brain oxidation and inflammation)
Glutathione (8) or N-acetyl Cysteine (NAC)(9) – protects the brain and improves methylation thus having potential in dementia prevention.
Co-enzyme Q10 – protects the mitochondria in the brain from oxidative stress (10)
Resveratrol – resveratrol has antioxidant, anti-inflammatory and neuroprotective properties and prevents hippocampal brain damage. (11)

It doesn’t really make a lot of sense to supplement one without the others.

Individually, their impact on your brain health may be less than when combined. 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. Taking either cut risk by a quarter (12). A recent meta-analysis of all studies on factors that could prevent Alzheimer’s by one of our Scientific Advisory Board members – Professor Jin Tai Yu of Fudan University in Shanghai, China – shows that ‘either a high vitamin E or C intake showed a trend of attenuating risk by about 26%’ making these nutrients ‘grade 1’ top level prevention risk factors (13).

All those listed above – vitamin C, E, glutathione and N-acetyl cysteine, Coenzyme Q10 and resveratrol – work together and are often found in combined antioxidant supplement formulas. There are many other team player ‘cousins’ from B vitamins to minerals such as magnesium, selenium and zinc found respectively in greens, seafood, nuts and seeds.

There are two ways to increase your intake – through food and from supplements. 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 (is nuts and seeds), but most of all vitamin C (rich in berries, broccoli, peppers and other vegetables).

(Click here to read our guidance on supplements)

The higher the TAC score of your diet the lower is your risk of cognitive and memory decline. This was the finding of a recent study of 2,716 people over age 60. The researchers measured the TAC score from their diet, splitting them into the highest to lowest quarter of TAC score, and compared this to a number of memory tests. Those in the highest quarter, eating the most antioxidant-rich foods had half the risk of decreasing memory. The higher the TAC score the better their memory function was. (14)

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Go Rainbow, ‘Mediterranean’ and eat five or more servings of fruit and vegetables a day

So, what do you need to eat and drink to preserve your memory and protect your brain?

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 and as researchers drill down, we are learning what to eat and drink to keep your mind sharp and brain young, and how much.

The trick is to really start thinking of the colours you’re eating and gravitate for the strong colours.

Mustard and turmeric, for example, are strong yellows. Dijon mustard is great – no sugar. But if you like good old-fashioned English mustard go for it. Have a teaspoon every other day.

Add turmeric to almost any steam-fry, curry or soup. 

Bright oranges include butternut squash, sweet potato, carrots – but do buy organic. Translucent mass produced carrots are tasteless and have a higher water content, ie less actual carrot. 

Tomatoes are particularly good for you. Buy seeded, not seedless watermelons. Blend the flesh in a blender, perhaps with some ice. The black husk of the seeds drops to the bottom. The flesh of the seeds, full of essential nutrients, becomes part of this mouth-wateringly refreshing drink. Great for detox. Strawberries are a low GL fruit. Red, yellow, green and orange peppers are all rich in vitamin C.

Anything purple, magenta or blue is brilliant for you. From beetroots (eat them raw, grated into salads) to blueberries, blackberries and raspberries. Strawberries are particularly good. According to a study, part of the Rush Memory and Aging Project at Rush University, Chicago, having a higher intake cut Alzheimer’s risk by a quarter. They are high in both vitamin C and flavanoids, a high level of which were also confirmed to cut risk by a third. (15)

Strong greens are always beneficial – from spinach, kale, Brussels sprouts, broccoli, tender stem, watercress, rocket, asparagus, artichoke, green beans, peas, kohlrabi, and cauliflower (although not green).

Polyphenol power

Some of these foods are particularly rich in ‘polyphenols’ a group of health promoting molecules which also includes flavonoids, sometimes called flavanols.  Blue foods such as blueberries contain another polyphenol called anthocyanins. Tea, the cacao in chocolate, red wine, red onions, olives and all the blueish berries are rich sources of polyphenols. Many of these polyphenol rich foods act as antioxidants but they do much more than this. They improve circulation in the brain, lower blood pressure and dampen down inflammation which lies behind many conditions from depression to dementia. Once again, the principle of what’s good for the heart is good for the brain.

One of the first important studies was carried out in Norway more than a decade ago by Eha Nurk and Helga Refsum and colleagues in Norway. (16)(17) They found that:

Tea – the more you drink the better. The tea benefit has been confirmed more recently in a study in Singapore, with green tea being marginally better than black tea.(18) However, this benefit was not found in a UK Biobank study, which reported tea and coffee drinking to be associated with worsening cognition compared to abstainers. (19)

Chocolate – peaks at 10g, or about 3 pieces – and let’s say dark, 70 or more percent, thus with less sugar, is likely to be better, as sugar is a strong indicator of cognitive decline. If a chocolate is 80% cacao that means almost 20% will be sugar. More recent studies giving cocoa, a rich source of flavanols, have shown improved cognition, possibly by improving circulation.(20) This has been confirmed in a big COSMOS trial involving over 20,000 people given a cacao extract supplement rich in flavanols versus a placebo for five years. (21) The reduction in cardiovascular risk was even greater than that of a Mediterranean diet.

Wine – consumption reduces risk of cognitive decline up to an intake of 125ml a day, which is a small glass. A thorough study in the British Medical Journal in 2018, which had followed over 9,000 people over 23 years, showed that both abstinence and drinking more than 14 units of alcohol a week, which is equivalent to a medium glass of wine (2.3 units) every day, also increases risk (22). This is consistent with studies showing that a small glass of wine a day decreases risk of cardiovascular disease. Red wine, high in resveratrol is likely to be most beneficial.

All the above are rich in a polyphenol called epicatechin. Jeremy Spencer, an advisor to Food for the Brain, who is Professor of Nutritional Biochemistry and Medicine at the University of Reading, where he specialises in studying the health benefits of polyphenols and other compounds in plants, has shown that these polyphenol rich plants improve blood brain flow in specific regions of the brain that improve attention, decision-making, impulse control and emotion, thus improving overall ‘executive’ function (23). What’s more, the level of flavanols you have in your bloodstream predicts your memory. The biggest impact of increasing flavanols, was seen in the COSMOS study, in those in the lowest third for dietary intake specifically seeing improvement in aspects of memory that link to the hippocampus, that central area of the brain that degenerates in Alzheimer’s (24).

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The Best Fruit and Veg to Eat for Your Brain

Which vegetables pack the biggest punch as far as polyphenols and antioxidants are concerned and are also lower in sugar or low GL?

Taking all these factors into account – the GL, antioxidants and polyphenols these are the dozen best rated fruit and veg. But do not think of this list as finite as more and more research reveals the amazing healing power of nature’s fruits and vegetables.

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The optimal intake for brain protection is 5 to 6 servings of fruit and veg a day. 

Half a plate of a main meal counts as two. A handful of berries would count as one. So, if half your plate for two main meals is vegetables, and you had some berries with your breakfast and another piece of fresh fruit or perhaps some broccoli heads or tenderstem or carrots dipped in hummus as a snack, or half an avocado with some high polyphenol olive oil, you’ve achieved six servings.

The first step is to eat ‘whole’ foods, and especially fresh plant foods with an emphasis on those listed above that are more likely to be high in antioxidants and polyphenols. (Also see the Alzheimers Prevention Diet.) There are some nutrients such as vitamin C for which just eating whole foods doesn’t guarantee you are achieving an optimal intake and are well worth supplementing.

My advice is to supplement 500mg to 1,000mg of vitamin C twice a day and also take an antioxidant formula or antioxidant rich multivitamin containing vitamins A, C, E, lipoic acid, glutathione or NAC, resveratrol and CoQ10.

Summary

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References

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