Tuesday, January 4, 2011

B-12: Stay Brainy As You Age

Like vitamin D, a B-12 deficiency is often found in older adults. In fact, vitamin B-12 is actually fairly easy to come by in a typical diet. Instead, low B-12 status occurs because of how the digestive system ages. In about 30% of older people, the lining of the stomach withers, secretes less gastric acid, and consequently loses the ability to extract B-12 from food protein. Studies have shown that low B-12 levels correspond to a decrease in memory and mental ability in the elderly.

* Vitamin B-12 can be found in animal foods like chicken, dairy, eggs, fish, and meat

* Cognitive impairment is two times as common in people with low B-12 status as compared to those with more elevated levels

* Roughly one out of five Americans aged 60 or older has low B-12 status

In the Women’s Antioxidant and Folic Acid Cardiovascular Study, researchers found that women aged 65 and older were less likely to decline on memory tests if they received B vitamins than if they got a placebo.
Interestingly, the answer isn’t as simple as popping a multivitamin. Although high B-12 status is associated with better cognitive function, that ability seems to be hindered by large amounts of unmetabolized folic acid. Folic acid occurs naturally in food like fruits and vegetables, but is frequently added to breakfast cereals, flour, and rice. Naturally occurring folic acid is converted to easily digested folate, but unmetabolized folic acid lingers in bodily tissues. When both unmetabolized folic acid and B-12 levels are high, they seemingly cancel each other out and the cognitive benefits disappear.

The bottom line: For those over 60, aim for a balanced diet that offers plenty of dairy, eggs, and meat, but try to avoid foods artificially fortified with folic acid. Choose a multivitamin with 6 mcg of B-12 (100% of the daily value) and the lowest dose of folic acid to reap the greatest health rewards.

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