A Neuroprotective Diet Against Alzheimer’s Disease

With the coming new year comes new existential dreads. For me, it’s the mortality and well-being of friends and family that fills me with trepidation. While old age can be a blessing, it can be a source of incredible pain when memories and personality begin to permanently fade and warp—a death of the person long before their actual demise. Such is what happens in the context of dementia, with Alzheimer’s being the most well-known cause.

The genetic component

Undoubtedly, Alzheimer’s disease has a genetic component; persons carrying the gene variant APOE-e4 are at higher risk for having Alzheimer’s disease than those with the gene APOE-e3, due to the impaired ability of proteins coded by e4 to remove toxins from nerve tissue[1]. Thankfully, there is mounting evidence that diet plays an equally important role in preventing or slowing Alzheimer’s disease onset.

Higher risk for Diabetics 

Poorly controlled type 2 diabetes mellitus is associated not only with obesity and chronic hyperglycemia, but also with Alzheimer’s disease; the high blood sugar levels seen in diabetes can increase your chances of getting dementia by 58% compared to keeping them within the normal range[2]. This is thought to be because high sugar concentrations can cause proteins to malfunction, one of these being amyloid-beta, which forms deposits in the brains of those with Alzheimer’s disease[3]. Adhering to your treatment plan if you have diabetes, or ideally taking steps to prevent type 2 diabetes altogether, by adopting a healthy body weight through moderate calorie-restriction and active lifestyle, can go a long way in avoiding this devastating neurodegenerative disease[4].

Nutrition to the rescue

What you eat is as important as how much you eat when it comes to a neuroprotective diet. A proper dietary intake of essential fatty acids (omega-3 and omega-6), folate, and Vitamin E through the consumption of nuts, fish and poultry, fruits, cruciferous and green leafy vegetables is linked with neuroprotection, while cognitive decline is linked with high butter/high-fat dairy, red and organ meat intake (foods which are high in saturated fat and calories)[5].

Anti-oxidants

Moderate red wine consumption (which is 3 or fewer drinks per day for men, 2 or fewer drinks per day for women—no more than five times per week) may offer a novel way to protect against Alzheimer’s disease. Red wine contains a high concentration of resveratrol, a compound found not just in the skin of grapes but also in peanuts and many types of berries. Resveratrol is thought to maintain the proper functioning of the blood-brain barrier and to promote a healthy lifespan in humans by mimicking what happens to the body during calorie-restriction and exercise[6].

The antioxidants found in fruits and vegetables can guard against the damage caused by the waste by-products of metabolism (hydrogen peroxide, for example), which are toxic to the brain: Vitamin A, Vitamin C, Vitamin E, lutein, alpha-carotene, zeaxanthin, and beta-cryptoxanthin are antioxidants that are depleted in persons with Alzheimer’s disease[7], with higher intakes of antioxidants conversely shown to offer protection [9], [10], [11]. While concentrates of antioxidants can be purchased in pill form, it is better to get them from food since antioxidants work in systems rather than in isolation—concentrated doses of antioxidants can actually act in the opposite manner, causing harm to the body and brain.

Vitamin K has also been implicated with better cognition and memory in the elderly[8] (note that if you are on a medication that affects blood-clotting, such as Warfarin, speak to your doctor before increasing Vitamin K intake). You can find this nutrient mainly in green leafy vegetables.

Share the information

If you think or fear that a loved one might be at risk of developing Alzheimer’s disease, please print this article and read it to them. While such dietary changes might not fully prevent neurodegeneration, it will reduce their chances and at minimum will significantly slow the progression of cognitive decline.

- Tyler Feeney-

M.Sci (c) in Dietetics

Disclaimer: The information provided is meant to spread knowledge and induce interest for educational purposes. It is based on limited research. We try to pull the overall message of the literature, but further research may be necessary.  What is done with the information or suggestions is solely the consumers decision. The information provided is not meant to treat or diagnose any medical condition. References are provided for informational purposes only and do not constitute endorsement of any website or other sources.

References

1.       Liu, C. C., Kanekiyo, T., Xu, H., & Bu, G. (2013). Apolipoprotein E and Alzheimer disease: risk, mechanisms and therapy. Nature Reviews Neurology, 9(2), 106-118.

2.       Li, T. C., Yang, C. P., Tseng, S. T., Li, C. I., Liu, C. S., Lin, W. Y., ... & Lin, C. C. (2017). Visit-to-Visit variations in fasting plasma glucose and HbA1c associated with an increased risk of Alzheimer disease: Taiwan Diabetes Study. Diabetes Care, 40(9), 1210-1217.

3.       Chao, A. C., Lee, T. C., Juo, S. H. H., & Yang, D. I. (2016). Hyperglycemia Increases the Production of Amyloid Beta‐Peptide Leading to Decreased Endothelial Tight Junction. CNS Neuroscience & Therapeutics, 22(4), 291-297.

4.       Van Cauwenberghe, C., Vandendriessche, C., Libert, C., & Vandenbroucke, R. E. (2016). Caloric restriction: beneficial effects on brain aging and Alzheimer’s disease. Mammalian Genome, 27(7-8), 300-319.

5.       Diet, A. P. (2010). Food Combination and Alzheimer Disease Risk. Archives of Neurology, 67(6), 699-706.

6.       Fernández, A. F., & Fraga, M. F. (2011). The effects of the dietary polyphenol resveratrol on human healthy aging and lifespan. Epigenetics, 6(7), 870-874.

7.       Rinaldi, P., Polidori, M. C., Metastasio, A., Mariani, E., Mattioli, P., Cherubini, A., ... & Mecocci, P. (2003). Plasma antioxidants are similarly depleted in mild cognitive impairment and in Alzheimer’s disease. Neurobiology of Aging, 24(7), 915-919.

8.       Presse, N., Belleville, S., Gaudreau, P., Greenwood, C. E., Kergoat, M. J., Morais, J. A., ... & Ferland, G. (2013). Vitamin K status and cognitive function in healthy older adults. Neurobiology of Aging, 34(12), 2777-2783.

9.       Dai, Q., Borenstein, A. R., Wu, Y., Jackson, J. C., & Larson, E. B. (2006). Fruit and vegetable juices and Alzheimer’s disease: the Kame Project. The American journal of medicine, 119(9), 751-759.

10.    Devore, E. E., Kang, J. H., Breteler, M., & Grodstein, F. (2012). Dietary intakes of berries and flavonoids in relation to cognitive decline. Annals of Neurology, 72(1), 135-143.

11.  Cabrera, C., Artacho, R., & Giménez, R. (2006). Beneficial effects of green tea—a review. Journal of the American College of Nutrition, 25(2), 79-99.