Damage, lack of vitamin d

Damage, lack of vitamin d

Low levels of vitamin D may cause declines in thinking, learning and memory in older men and women, according to a new study in the March 12 2010 issue of Archives of Internal Medicine..

An early study reported at foodconsumer.org showed low vitamin D was linked with cognitive decline in people with dementia, particularly Alzheimer's patients.

The current study led by David J. Llewellyn, Ph.D., of University of Exeter, England, and colleagues showed that older people with low levels of vitamin D were more likely to experience cognitive decline over a six-year period.

For the study, the researchers assessed blood levels of vitamin d in 858 men and women aged 65 or older at baseline. Participants completed interviews and medical exams and provided blood samples.  Three tested were administered at the beginning of the study and again after three and six years.

The researchers found those who were severely deficient of vitamin D,; defined as having blood levels of 25-hydroxyvitamin D of less than 25 ng per mL, were 60 percent more likely to have substantial cognitive decline during the six year follow-up and 30 percent more likely to have declines on the test measuring executive function than those with sufficient levels.

"Vitamin D: has been known for many years to play a critical role in skeletal health, such that very low levels of this hormone (less than 20 nanomoles per liter) can cause osteomalacia, a disorder of impaired bone mineralization," says Andrew Grey, M.D., and Mark Bolland, M.B.Ch.B., Ph.D., of University of Auckland, New Zealand in an accompanying editorial.

"More recently, observational studies have reported inverse associations between levels of serum 25-hydroxyvitamin D, the metabolite that best reflects overall vitamin D status, and the risk of a wide range of disease, including cancer, vascular disease, infectious conditions, autoimmune diseases, osteoporosis, type 2 diabetes mellitus and obesity."

Other studies reported early on foodconsumer.org suggest that low vitamin D can not only cause more cognitive decline in Alzheimer's disease, but also lead to the development of Alzheimer's in the first place..

Three studies presented at the Alzheimer's Association International Conference in Honolulu suggest that physical exercise, tea and vitamin D may all help prevent Alzheimer's disease..

An estimated 40 to 100 percent of older people in the U.S. suffer vitamin D deficiency and a few millions of them live with Alzheimer's disease..