Most people wouldn’t be surprised to learn what they eat may influence the way their brain ages, but a growing body of evidence suggests that changes in intestinal bacteria – some treatable – may also impact mental abilities as we grow older. Together with Stephen Collins of McMaster University in Canada, a team of ARC researchers has summarized the evidence in a new article.
An increasing amount of research connects diet and brain aging. Perhaps the most consistent and encouraging finding is the positive impact of a diet that includes a rainbow-colored spectrum of fruits and vegetables, fatty fish, extra-virgin olive oil, a moderate amount of nuts, and little meat. Such a diet can reduce the risk of obesity and overweight, diabetes, and high blood pressure – all risk factors for cognitive decline. It may also promote healthy intestinal bacteria, dampen inflammation, and hinder oxidative stress, a toxic process that can lead to negative changes in the body, including the brain.
Researchers have learned that focusing on the relationship between single nutrients like vitamins E, C, A, and B and cognitive decline often leads to inconsistent results. This is even more obvious when vitamin intake happens through supplementation rather than through eating vitamin-rich foods. Concentrating on brain-friendly food items (like cocoa, blueberries, and green tea, to mention just a few) has given more consistent results, and focusing on food groups like fruits and vegetables, even more so. But even brain-friendly food groups are not enough on their own.
“There’s no magic food or magic pill so far,” says first author Barbara Caracciolo. “You have to go back to following a balanced diet, like your grandmother used to . . . We have to think in terms of a whole dietary pattern rather than focusing on specific nutrients or food items.”
Of all the eating patterns examined thus far, the one that seems the most beneficial for the brain is the Mediterranean diet. It contains many brain-friendly nutrients, food items, and food groups and little that is unhealthy.
The article also describes exciting findings that link cognitive decline to changes in intestinal bacteria. Researchers suspect such changes can cause low-grade inflammation in the digestive system that may lead to inflammation of brain tissue and cognitive decline. Alterations in intestinal bacteria are common in aging and can be exacerbated by disease and dietary changes. Dietary changes in old age may occur because of lower income, reduced mobility, memory problems, the loss of a spouse or partner, and even long-term intake of institutional food.
The overview is part of a series of papers written by researchers involved in the EU-funded study, “New dietary strategies addressing the specific needs of the elderly population for healthy aging in Europe” (NU-AGE). In this five-year study, older people at several centers across Europe are given dietary advice based on the Mediterranean diet and even food items to help them follow this diet. The aim is to use diet to counteract or slow the aging process.
For full article, please follow this link: http://dx.doi.org/10.1016/j.mad.2013.11.011