There has long been a hope that people in search of a fountain of youth for the brain could look no further than their dinner plate.
Just last month, researchers reported that people who eat baked or broiled fish at least once a week may be protecting their brains from Alzheimer's and other brain problems.
But it's been surprisingly difficult to figure out for sure whether the food people eat really can protect their brains. For one thing, it's incredibly hard to identify exactly how individual foods, or their components, may influence the brain.
Perhaps more importantly, how can you know for sure it's really what people eat as opposed to other things that tend to go along with a healthful diet, like exercise?
A new study, however, makes a stab at teasing this apart.
Gene Bowman of the Oregon Health & Science University in Portland and his colleagues decided to test blood samples from 104 elderly volunteers for a variety of nutrients. They thought this would be more reliable than counting on people to remember exactly what they ate,
They also gave them a battery of tests to measure their memory and thinking abilities. And 42 of the subjects underwent MRI scans to measure the overall size of their brains.
Those who tested high in omega-3 fatty acids and vitamin D, which are commonly found in fish, and in vitamins C, E and B, which are often found in vegetables, were less likely to have their brains shrink, and were more likely to score higher on the memory and thinking tests, the researchers report in the Dec. 28 issue of the journal Neurology.
In contrast, those who ate a lot of food containing trans fats — found in margarine, some packaged food, fast food and baked goods — tended to experience more brain shrinkage and score more poorly on the thinking and memory tests.
Now, the researchers caution that more research was needed to validate the findings, which could help "decipher the key nutrient combinations and population best suited" to be tested in additional studies evaluating individual parts of the diet.
In an editorial accompanying the research, Christy Tangney of Rush University Medical Center in Chicago and Nikolaos Scarmeas of Columbia University in New York agree the work needs to be confirmed by studies involving a "larger, more ethnically diverse sample of older adults." In addition other nutrients, such as resveratrol in red wine, antioxidants in olive oil and nuts, and amino acids in fruits, need to be evaluated, they say.