Serum vitamin B levels and Dementia.




American Journal of Clinical Nutrition

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As baby boomers age and the senior population swells, more people than ever before are faced with the impact of aging on the brain. Loss of memory and thinking ability is one of aging's most tragic consequences. Without memory, we lose our sense of identity and relationship to the world around us. A haunting song about aging recorded by Simon and Garfunkel in the 1960s ends with the words: "Preserve your memories, they're all that's left you." How sad that so many people spend their final years with few memories left intact.

In its beginning stages, Alzheimer's can be a difficult disease to spot; the changes in memory and behavior are barely noticeable at first. The disease may worsen within the first several years or take as long as twenty to progress. Average survival time after diagnosis is generally four to eight years. Memory loss gradually worsens, along with a decline in ability to perform routine daily tasks. Late stage Alzheimer's sufferers experience increasing disorientation, impaired judgment, personality changes, difficulty in learning, and a loss of language skills. As yet, there is no cure for Alzheimer's disease.

Several studies have documented the fact that supplementation with folic acid, vitamin B6, and vitamin B12 can effectively lower homocysteine levels. There are wide variations in the dosages of these B-vitamins used in different studies. It is now recognized that even moderate elevations of homocysteine represent a strong independent risk to cardiovascular disease and potentially Alzheimer’s disease.

A recent study investigated the role of blood levels (serum) of homocysteine, folate, and vitamin B12 in relation to Alzheimer’s disease (AD) and vascular dementia (VaD). This population study took samples form 228 participants, 55 non-demented, 81, mildly demented, and 92 with a mild stage of AD. Those with the lowest folate levels had an increased risk of mild cognitive impairment and dementia. High levels of homocysteine were positively linked to AD and dementia. In addition, using a evaluation called the Clinical Dementia Rating, those with a the lowest scores had the highest levels of homocysteine. The authors concluded that “These findings suggest that relative folate deficiency may precede AD and VaD onset.”1


1. Quadri P, et al. Homocysteine, folate, and vitamin B-12 in mild cognitive impairment, Alzheimer disease, and vascular dementia. Am J Clin Nutr. Jul 2004;80(1):114-122.