New York: Folic acid may lower the risk of Alzheimer’s, say US doctors.

The finding follows a study of nearly 1,000 elderly people which discovered that those with higher levels of this B vitamin were less likely to suffer mental deterioration.

The research was carried out by Columbia Univesity Medical Center spent six years examinng the diet of 965 healthy adults with the average age of 75. The one in five who went on to develop Alzheimer’s had the lowest levels of folic acid.

Folic acid has also been found to be useful in improving the memory of people aged over 50.

Folic acid, a B vitamin is found mostly in dark green vegetables such as asparagus but is easily destroyed by cooking. Supplements provide a form of the vitamin more easily taken up by the body. And the researchers recommended that both natural and supplement forms of the vitamin were the best choice for older people.