Last month saw the International World Alzheimer's Day, where Alzheimer associations across the globe unite to increase awareness of this devastating disease. Although the causes of Alzheimer’s disease remain largely mysterious, scientists have identified a genetic mutation associated with early-onset Alzheimer’s disease and a range of likely risk factors for late-onset Alzheimer’s. Although the importance of risk factors may differ between individuals, Alzheimer’s disease is most likely the result of a combination of genetic, environmental and lifestyle factors. While no single nutrient can prevent this condition, good nutrition may help reduce the risk of Alzheimer’s disease in some people. This is because dietary factors can influence a range of processes thought to be involved in the pathological changes seen in the brain in Alzheimer’s disease. For example, age-related changes in the brain that are thought to contribute to this form of dementia include:

• Atrophy (shrinking) of certain parts of the brain
• Inflammation
• Production of free radicals
• Mitochondrial dysfunction.

Certain nutrients, such as antioxidants, have been found to help guard against these kinds of changes, thereby supporting healthy brain activity throughout life. What this translates to in dietary terms is:

• Eating a variety of fresh fruits and vegetables
• Choosing healthy whole grains
• Opting for lean protein sources, such as legumes and pulses
• Following a predominantly plant-based diet that is rich in fibre
• Achieving and maintaining a healthy weight.

Reducing intake of foods that promote undesirable inflammation and vascular dysfunction (including high blood pressure) can also help. In practice, this means cutting back on:

• Foods with a high saturated fat and cholesterol content, like fatty meats and fried foods
• Sugar and refined grain products

Increasing your intake of antioxidants is also a smart move for cognitive health. Not all antioxidants can cross the blood-brain barrier however, meaning that while many help reduce oxidative damage in general, they do little to support brain health. Some key antioxidants and other nutrients have been found to exert neuroprotective effects. These include essential fatty acids, amino acids, indoles, piperidine, isoquinolines and polyphenols found in plants, such as:

• Curcuminoids – found in turmeric (but generally not well absorbed in dietary forms)
• Rosmarinic acid – found in rosemary and in perilla oil
• Resveratrol – found in grape skins and the skins of other (typically red) fruit, as well as in peanuts
• Acetyl-L-carnitine – found predominantly in animal products, but also in asparagus and whole wheat
• Omega-3 (ω-3) polyunsaturated fatty acids – found in chia, algal oil, flaxseed and in some fatty fish and fish oil supplements
• Epigallocatechin-3-gallate (EGCG) – found predominantly in green tea
• Theanine – found in black tea and in green tea
• Caffeine – found in tea, coffee and in some herbs.

Vitamins E, C and D have also been associated with neuroprotective activity and are essential for al-round good health. Some herbal remedies, such as pycnogenol and ginseng, have also been investigated for their potential to help delay the progression of Alzheimer’s disease, with studies showing significant promise for these natural interventions. There is no magic pill for preventing or curing Alzheimer’s disease, but we can take steps to address a number of risk factors, including stopping smoking, getting regular exercise, eating well and doing what we can to minimise the risk of head injury and concussion.  

For more information about World Alzheimer’s Day, and for support and advice, visit http://www.alz.co.uk/world-alzheimers-day

References Mi, W., van Wijk, N., Cansev, M., et al. (2013). Nutritional approaches in the risk reduction and management of Alzheimer's disease. Nutrition, Sep;29(9):1080-9. Petraglia, A.L., Winkler, E.A., & Bailes, J.E. (2011). Stuck at the bench: Potential natural neuroprotective compounds for concussion. Surgical Neurology International, 2, 146.