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As we age there are a number of health concerns that can begin to surface, one of which is Alzheimer’s disease. This disease is suggested to be the result of lifestyle, genetic and environmental factors according to physiological, epidemiological and some intervention studies. The following are factors that have been found to be neurodegenerative (characterized by degeneration of nervous tissue) and factors that are neuroprotective (strategies that protect neurons from injury) against Alzheimer’s.

Neurodegenerative factors

• Excess Fat, Sugar, Calories and Weight
Excess fat, sugar and calories can contribute to oxidative stress throughout the body and is associated with weight gain. Some studies have shown that free radical damage inflammation from oxidative stress and increased waist circumference is associated with Alzheimer’s.

• Pesticides, herbicides and metals
Large doses of pesticides, herbicides and metals have been found to be neurotoxic. However, current guidelines suggest that limited exposure to aluminum does not pose as a significant health risk. Some metals in excess may hyperactivate “scavenger” cells leading to cell damage. Associations between iron, zinc, manganese, copper and magnesium, and Alzheimer’s disease is unclear.

• Advanced Glycation End Products (AGEPs)
AGEPs are a group of endogenous sugar-protein compounds that have properties that increase inflammation and oxidation. AGEPs are thought to contribute to Alzheimer’s disease. These compounds are found in high sugar and fried foods, along with foods that are have been cooked with high or dry heat. Use food preparation techniques such as stewing, boiling, poaching and steaming that can assist in reducing the body’s AGEPs and delay the development of Alzheimer’s.

• Aspartame
At present no specific evidence has been found to date that connects aspartame with mental function changes.

Neuroprotective Factors

• Antioxidants
A number of antioxidants including vitamins A, C, E, Beta-carotene, selenium, anthocyanins, polyphenols and compounds of selected culinary spices and herbs have been found to assist in minimizing brain lipid oxidation. Vascular diseases are associated with Alzheimer’s and the benefits of antioxidants for vascular function may in turn represent mechanism for decreasing the risk of Alzheimer’s.

• B Vitamins
Vitamin B12, B6, folate, niacin and thiamine deficiencies can contribute to cognitive decline. Hyperhomocysteinemia can result from deficiencies of these cofactors and is an independent risk factor for Alzheimer’s. However, to date there is no clear evidence that supports regular supplementation.

• Essential Fatty Acids (EFAs)
Fatty acids such as omega-3s and omega-6s are essential to the body. This means our bodies don’t make them they must be consumed in the diet. If however, there is excess of saturated fat and trans fats versus EFAs during the time cells are being formed, they will preferentially be incorporated into the cell membranes. This can alter membrane enzyme activity, plaque formation, inflammation and alter the permeability of the membrane to a point where toxins could cross the blood brain barrier. It is recommended to emphasize omega-3 fatty acids in the diet to reduce oxidative damage. Omega-3s come from fatty fish like salmon and sardines, flaxseeds, walnuts and fortified products (eg. Milk, eggs, bread, cereals).

• Choline
The mechanism behind the importance of choline in the diet is its effect on accelerating the synthesis and release of acetylcholine a neurotransmitter that is thought to be in short supply in Alzheimer’s. Choline can be found in such foods as milk, liver, eggs and peanuts.

Bottom line: While individual nutrients may not be effective in reducing the risk of Alzheimer’s disease, a combination of nutrients consumed by eating a diet rich in variety, nutrients, fibre and low in fat and sugar can be more effective. Aim to incorporate as many colours on your plate as possible to increase the number of antioxidants your body receives.