Fish is brain food -- right? It certainly might be.

Experts typically recommend eating fish twice a week because of the omega-3 fatty acids that make it a heart-healthy source of nutrition. Now, it seems fish might be brain-healthy too.

Preliminary studies suggest that the wonder of omega-3 (docosahexaenoic acid or DHA, to be more official) also boosts brain power. Makes sense since DHA comprises much of the cell membranes in our brains. Food folks love this news and are busy adding DHA to foods like yogurt, soy milk, and eggs, while marketing their products with clever slogans. Do their food items really enhance mental performance, though?

Some research says yes, it may reduce the risk of Alzheimer's disease and the cognitive decline that precedes it. It also might result in superior cognitive performance in children whose moms supplement with DHA during pregnancy. There's no clear evidence that eating DHA-rich foods improves mental function in healthy adults, however. But it's always wise to eat healthy foods -- and fish is one of them. And since DHA may one day be a proven brain enhancer, you might trying getting 200 mg per day in your diet -- that's three times what the average American gets now.