In the September 2006 issue of the American Journal of Medicine, Dr. Qi Dai at Vanderbilt University examined the risk of developing Alzheimer?s disease in 1836 older Japanese-American subjects free of dementia based on cognitive function tests. Over the next 7 to 10 years, Dr. Qi Dai and colleagues monitored the cognitive function of their subjects about every 2 years and gathered information about their dietary, exercise, smoking, and other behaviors. The results showed a dramatic reduction of 76% in the risk of developing Alzheimer?s disease in those subjects consuming the most fruit and vegetable juices compared to those who consumed less than 1 serving of fruit or vegetable juice per week.How Might Fruits & Veggies Cut the Risk Of Alzheimer?s?Growing evidence shows that a diet high in saturated fat, trans fat and cholesterol, salt, and refined carbohydrates leads to excessive levels of beta-amyloid protein building up in the brain. There is now little doubt this beta-amyloid leads to the growth of plaques that damage and destroy brain cells. It is known that people who inherit the apo E-4 allele tend to run higher levels of blood lipids than those with the apo E-2 or E-3 alleles and are at increased risk of developing early coronary artery disease. They are also at much higher risk of developing Alzheimer?s disease.Dr? Qi Dai suggests that oxidative damage caused by these beta-amyloid plaques may be mediated by their generation of free radicals.Fruits and vegetables are rich in a group of powerful antioxidant phytochemicals called polyphenols. It may well be that consuming more of these polyphenols by eating more fruits and vegetables and/or drinking their juices slows the free radical generation process associated with the build-up of beta-amyloid plaques.Dr. Qi Dai?s results showed that the apparent protective effect of these plant-derived phytochemicals was greatest in those who were inactive and in those who had the apo E-4 allele.On the other hand he found no significant association with an increased intake of antioxidant vitamins E & C and beta-carotene with a reduced risk of Alzheimer?s disease.Dr. Qi Dai concluded, ?Fruit and vegetable juices may play an important role in delaying the onset of Alzheimer?s disease, particularly in those who are at high risk for the disease.?Of course, eating whole fruits and vegetables would provide a similar amount of polyphenols and be more satiating than simply drinking juice that is devoid of fiber. Getting more satiety out of your calories leads to weight loss and improved insulin sensitivity and also lowers ?bad? blood lipids that also appear to play a role in promoting Alzheimer?s disease. Also most commercially available vegetable juices are very high in salt, which elevates blood pressure. Higher blood pressure is a well-established risk factor for declining mental function in older people. Therefore, it is probably better for those with excess body fat to consume the fiber-rich fruits and vegetables rather than the juice.

Bottom Line:The best way to ward off the threat of Alzheimer?s disease and other forms of senility is to eat a diet high in fruits, vegetables, whole grains, and beans and low in saturated and hydrogenated fats, cholesterol, salt, and refined carbohydrates. This diet has been proven to be optimal for health and for avoiding other diseases, too.By James J. Kenney, PhD, RD, FACN.