A recent study conducted in Finland and published in "Neurology" found that individuals with higher blood levels of vitamin B12 were less likely to develop Alzheimer's disease.

Researchers analyzed blood samples from almost 300 study participants aged 65-79 who exhibited no symptoms of the disease. They also tested for levels of an amino acid called homocysteine, which has been shown to increase the risk of developing Alzheimer's disease.

Seven years after the initial testing, 17 individuals had developed Alzheimer's. Researches re-tested all participants and found that those who had developed the illness had the highest levels of homocysteine and the lowest levels of vitamin B12. Vitamin B12 is also know to lower levels of homocysteine in the blood.

Although a recent National Institutes of Health panel stated that no food or vitamin is know to ensure protection against Alzheimer's, the role of healthy diet is indisputable. Foods rich in B12 include liver, eggs yolks, nuts, whole grains, sweet potatoes, bananas, oranges, spinach, broccoli and brussel sprouts.