The risk factors for heart disease are well known and often controllable, but Alzheimer’s disease is a more capricious foe. Beyond choosing your parents carefully, there are few sure bets for lowering your risk. Could good nutrition and exercise help? The evidence is by no means conclusive, but it’s provocative. Here are some of the hints that science has yielded.
Fats in the diet Several large studies have found that diets loaded with saturated fats, trans-fats and cholesterol are associated with a greater risk of Alzheimer’s and other forms of dementia. But a recent large study from the Netherlands found no such link.
Blood levels of cholesterol There is some evidence that high levels of total cholesterol or LDL (bad cholesterol) can increase the risk of Alzheimer’s disease. A lack of HDL (good cholesterol) may have a similar effect. Several studies have found that people who take the cholesterol-lowering statin drugs to protect their hearts may also lower their risk of Alzheimer’s. Researchers are now studying the statins specifically for that purpose, but the results are not yet in.
High blood pressure Some studies find that people with high blood pressure are at greater risk for Alzheimer’s disease, but it’s unclear whether treating high blood pressure reduces the risk. Diet and exercise can lower blood pressure.
Fish oils A French study has found that people who eat fish at least once a week are less likely to develop dementia. Laboratory studies suggest that fish oils (particularly omega-3 fatty acids) help control inflammatory processes that are associated with Alzheimer’s.
Antioxidant supplements Some studies suggest that diets rich in antioxidants (beta carotene, selenium, vitamins C and E) may reduce the risk of Alzheimer’s disease. Antioxidant pills have not been shown to prevent Alzheimer’s, but at least one controlled study suggests that high doses of vitamin E may slightly slow progression of the disease.
Homocysteine Several studies have linked elevated blood levels of homocysteine (an amino acid our bodies generate in the course of normal metabolism) with the development of Alzheimer’s. Vitamins B6, B12 and folic acid help control homocysteine levels, whether you get them in food or in pill form.
Exercise Some studies find that people who exercise regularly are at lower risk of Alzheimer’s and other forms of dementia, but the evidence is not conclusive.
It will take years to gauge the significance of these factors. How should we live in the meantime? If you consider the known benefits of exercise and a healthful diet, it’s a no-brainer.
