Environmental Nutrition

Plenty of diets are designed to help you lose weight, or reduce the risk of developing cardiovascular disease, diabetes or high blood pressure. But there is also research that clearly indicates a connection between what you put on your plate and the health of your brain. In other words, a healthy diet could mean the difference between staying sharp into old age or developing dementia or Alzheimer's disease. Science suggests that the closer you adhere to a healthy diet and the longer you stick with it, the more likely you are to avoid the cognitive decline that sometimes occurs with aging. A healthy diet can even slow cognitive decline in stroke survivors, who are twice as likely to develop dementia compared to the general population.

The diet-brain connection

It turns out that there are plenty of possible connections between your diet and your brain. Studies have found that diets that provide the B vitamin folate, vitamin E, omega-3 fatty acids, carotenoids and flavonoids are associated with slower rates of cognitive decline, while intake of saturated and hydrogenated fats have been associated with dementia. Foods that provide these beneficial nutrients help to keep chronic inflammation in check, not only in the brain, but in the entire body.

From the gut to the brain

Another seldom considered connection is between the gut (large intestine) and the brain. While they may be at opposite ends of the body, what's happening in the gut affects brain function. Researchers have uncovered how changes in the gut might be linked to inflammation in the brain. The gut is inhabited by trillions of bacteria, both good and bad, collectively called the microbiome. By eating healthful foods, such as cruciferous vegetables (i.e., broccoli, Brussels sprouts, cauliflower), beans, blueberries, yogurt, kefir, miso, yogurt and whole grains that feed the good bacteria, inflammation is reduced in the brain. Preliminary research suggests that the state of the microbiome can also affect your mood and energy level, and may even play a role in the development of psychiatric disorders, like depression.

Enter The MIND Diet

The Mediterranean and DASH (Dietary Approaches to Stop Hypertension) diets were originally developed to help improve cardiovascular health. A hybrid of these diets, called the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND diet) is gaining attention for its potentially positive effect on preserving cognitive function and reducing dementia risk in older individuals. Cognitive function is a reflection of brain health. Developed by Martha Clare Morris, Ph.D., nutritional epidemiologist at Rush University Medical Center in Chicago, the diet has been found to offer real promise for maintaining brain health. In a recent study of 923 people ages 58 to 98 who were followed for 4.5 years, adherence to the MIND diet was associated with a slower rate of cognitive decline, equivalent to 7.5 years younger age, compared to those who didn't adhere to the diet.

According to the Global Council on Brain Health, a collaborative of the AARP and Age UK, DHA (docosahexaenoic acid, found in fish oils) is the most prevalent omega-3 fatty acid in the brain. This fatty acid found in seafood (see Tenets of the MIND Diet) has been shown to play an important role in the maintenance of brain cell membranes. A survey conducted by the AARP showed that people who typically eat fish or seafood every week report better cognitive function, compared to those who never eat fish or seafood.

At last year's Alzheimer Association's International Conference in the U.K, researchers from the University of California, San Francisco revealed that following either a heart-healthy Mediterranean diet or its close cousin, the MIND diet, can reduce future cognitive impairment by up to 35 percent. An earlier study found that among people who followed the diet rigorously, the risk of developing Alzheimer's was reduced by as much as 53 percent.

According to Claire McEvoy, Ph.D., M.Phil., R.D., also a researcher with the University of California, San Francisco, "The MIND diet as a whole seems to have the greatest benefit; the foods and nutrients work together. Of course, while you get the biggest result if you follow the diet completely, even little changes can have a significant impact."

(Environmental Nutrition is the award-winning independent newsletter written by nutrition experts dedicated to providing readers up-to-date, accurate information about health and nutrition in clear, concise English. For more information, visit www.environmentalnutrition.com.)