Millions of Americans have Alzheimer's disease, which is the most severe form of dementia associated with memory loss. Risk of the disease increases with age and the number of people age 65 and older is expected to grow to 72 million by 2030, with Alzheimer's cases doubling every five years for that age group, according to the National Institute on Aging. Ongoing research with vitamin B12 may have developed a link to help improve or delay declining memory.
Identification
Vitamin B12 is one of the eight B vitamins and has the largest and most complex chemical structure of all the vitamins. Known also as cobalamin, Vitamin B12 is unique because it contains cobalt. A water-soluble vitamin, B12 plays a key role in the metabolism of every cell in the body, especially affecting DNA synthesis in the brain and nervous system.
Sources
Good sources of vitamin B12 are protein from animals including fish, liver, shellfish poultry and meat such as beef, lamb, pork and venison. Many foods, especially breakfast cereals and milk, are fortified with vitamin B12. B12 is also available in supplement form or by injection.
Brain Shrinkage
According to a BBC report, older people with low vitamin B12 levels are six times more likely to experience brain shrinkage, which may be linked to development of dementia. A study published in "Neurology" examined a group with vitamin B12 deficiencies and noted increased signs of brain shrinkage over a five-year period. "The rate of shrinkage of the brain as we age may be partly influenced by what we eat," says Professor David Smith, director of the Oxford Project to Investigate Memory and Aging. This study suggests that consuming more vitamin B12 rich foods as part of a balanced diet might help protect the brain.
Alzheimer's Disease
"Age and Aging" published a study that connected vitamin B12 deficiency with Alzheimer's disease. Rotherham General Hospital in South Yorkshire found patients with Alzheimer's disease had lower serum vitamin B12 values compared to unaffected family members.
Dementia
The "Journal of Neurophsychiatry and Clinic Neurosciences" published a report that links vitamin B12 with dementia. The study found that elderly patients, deficient in B12 and suffering from cognitive impairment, improved after supplementation with vitamin B12. The "International Journal of Geriatric Psychiatry" examined a study of the effect of vitamin B12 on treating dementia and improving cognitive function in 123 patients with low B12 levels. Supplements did not reverse the dementia, but it did appear to prevent the condition from becoming worse. The study concluded that vitamin B12 might stop the progression of dementia, and help to improve frontal lobe functioning in patients with cognitive impairment.
Deficiencies
A vitamin B12 deficiency can result from gastritis or other diseases that cause a decrease in enzymes required to metabolize vitamin B12. Pancreatic problem or celiac disease can result in malabsorption of vitamin B12. Reduced absorption is often a problem in the elderly who may have decreased stomach acid necessary to utilize vitamins or in alcoholics with an inhibited ability to assimilate vitamin B12. Since food sources of vitamin B12 are from animal products, vegetarians are at risk of a deficiency.
References
- National Institute on Aging: Alzheimer Information: How Many Americans Have AD?
- BBC News: "Vitamin May Prevent Memory Loss": Liver and Shellfish
- Pub Med: Familial Alzheimer's Disease and Vitamin B12 Deficiency; McCaddon A. et al; 1994
- The Journal of Neuropsychiatry and Clinic Neurosciences: Dementia Associated With Vitamin B12 Deficiency; Norbert Goebels et al.; 2000
- The Vitamins and Nutrition Center: Vitamin B12 Deficiency and Dementia; Eastley R. Wilcock GK. Bucks RS.; 2000
- Oregon State University: Vitamin B12: Deficiency
