Fruits and Vegetables are Brain Food
~ December 1998 No.59 ~
It sounds like common sense and not state of the art science, but the latest results published in the Journal of Neuroscience1 have concluded that eating fruits and vegetables are good for your health. Rats were the subjects in the experiment, but humans can benefit from the findings.
We have always assumed that eating fruits and vegetables was good for health because they were good sources of a wide variety of vitamins (vitamin C in citrus fruit, vitamin A in carrots, folic acid in greens). Then, when the fibre craze came along, it became important to eat fruits and vegetables because they were good sources of fibre. 100 grams of apple for example contains 2.7 g of fibre while 100 grams of turnip contains 2.0 g of fibre.
Fruits and vegetables also contain antioxidants and it is the effects of these dietary sources of antioxidants on brain aging that was the subject of the report by Dr. James Joseph of the US Department of Agriculture Human Nutrition Research Center on Aging at Tufts University in Boston.
The brain is a strange organ. First, because it is not as dynamic as other organs in the body. The turn over of cells in the brain is almost zero, unlike the liver or the lung. This means that the brain is particularly sensitive to damage because once brain cells are injured or killed, they aren't replaced. Secondly it contains low concentrations of antioxidants. Antioxidants are know to be protectors of cells from a variety of environmental and metabolic insults. The brain is also a very active organ, so free radicals which can be very damaging to surrounding tissue are often produced. Without the protection of antioxidants, the brain tissue is vulnerable.
The experiment carried out by the US researchers showed that if rats are fed a diet that contains added antioxidant for six months, the rate of mental decline is slowed when compared to rats fed a conventional diet. Rats fed a diet containing spinach had the fewest age-related declines in mental function. Those eating added strawberry extract were next, followed by rats receiving added vitamin E. Vitamin E is often used as a standard in antioxidant studies because of its proven antioxidant properties.
The relation between antioxidant damage to the brain and the onset of Alzheimer's disease and Parkinson's disease has not been proven as yet, but there have been some indications in the scientific literature that there is a link. The phytochemicals in spinach and strawberry extract, particularly those with antioxidant properties, could provide protection against the onset of these degenerative diseases. However, experiments to prove their efficacity are difficult to carry out. Foods such as spinach and strawberry extract may be more effective than just pure vitamin E because foods and extracts contain a cocktail of phytochemicals rather than just one active ingredient.
A mixed diet with plenty of fresh fruits and vegetables is still probably the best dietary advise anyone can follow. And it now looks like strawberry milkshakes can be added to the list.