AD and the intake of Niacin.




J Neurol Neurosurg Psychiatry

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Alzheimer's disease (AD) is a debilitating disease that causes severe degeneration of brain tissue. Plaque deposits accumulate in the spaces between brain cells. The cells themselves form twisted, spaghetti-like masses called "neurofibrillary tangles." Why these changes happen in the brains of some people but not others remains a matter of speculation. Scientists are unsure as to which of these abnormalities occurs first, the plaque or the tangles. What triggers them in the first place is not known for certain.

A study recently investigated the role of niacin in the development of AD. Niacin is a water-soluble vitamin that can be produced in the body. It is instrumental in producing two of the body's important co-enzymes, which are further involved in more than 200 chemical reactions in the body. It is also important for metabolism of carbohydrates, fatty acids and amino acids, as well as energy production on the cellular level. Foods that contain niacin and its precursor, tryptophan, are considered sources of the vitamin. Organ meats, brewer's yeast, milk, legumes, peanuts, and peanut butter are the best sources of niacin. Lean meats, poultry, fish, and peanuts are good sources of both niacin and tryptophan.

This study stated that AD may be caused by severe niacin deficiency. Researchers used food frequency questionnaires to determine niacin intake among 3,718 participants aged 65 years or older. These individuals were given 4 cognitive function tests over a 5.5-year period. These tests determined the cognitive changes that occurred over a period of time. In a sample of 815 individuals tested for AD, 131 cases were diagnosed. The results showed that niacin intake had a protective role against AD as well as cognitive decline. Those who had a lower intake of niacin had a greater risk of AD or cognitive decline. This association was stronger in participants who did not have any form of cardiovascular disease. The authors concluded that dietary niacin may protect against AD and cognitive decline due to age.1


1. Morris MC, et al. Dietary niacin and the risk of incident Alzheimer’s disease and of cognitive decline. J Neurol Neurosurg Psychiatry. Aug 2004;75(8):1093-9.