Wednesday Sep 10, 2008 (foodconsumer.org) -- Taking vitamin B12 may help prevent brain shrinkage, according to a new study published in the journal Neurology.

This is only a possibility because researchers only found an association between high levels of vitamin B12 and reduced risk of developing brain shrinkage.

For the study, David Smith and Anna Vogiatzoglou of the University of Oxford analyzed blood samples from 107 healthy people ages 61 to 87 for the serum level of vitamin B12 and measured their brain volume.

They found low levels of vitamin B12 were associated with brain shrinkage.   People in the lower third of vitamin B12 levels were six times more likely to experience brain shrinkage than those in the upper third.

Vitamin B12 deficiency is not common in developed countries.  But an estimated 10 percent of people ages 60 or older are deficient of this vitamin due to certain healthy conditions.   Those who are at risk of deficiency include those with health conditions and vegetarians who do not use animal foods.

Absorption of vitamin B12 requires normal condition in the digestive system including the stomach, pancreas and small intestine.

Vitamin B12 is found rich in seafood including clams, mussels, crab and salmon fish.   Low levels are also found in other animal foods.  But plant foods do not contain any vitamin B12.   For this reason, vegetarians need to take vitamin B12 supplements.

The researchers said it is unknown whether taking a vitamin B12 supplements would prevent brain shrinkage which is linked to declines in thinking and memory. Because of this, they said it is too early to recommend taking the vitamin to prevent brain shrinkage.