7 March 2009

Does milk fight Alzheimer’s?

Alzheimer’s and milk
Dementia News (Alzheimer’s Australia): 4 March 2009
The recent media spotlight has been on milk and its putative capacity to prevent Alzheimer’s disease. This follows the publication of a paper in December 2008 in the American Journal of Clinical Nutrition in which two researchers reported on their review of evidence that cognition in the elderly may also be adversely affected at low levels of vitamin B12 in the blood above the traditional cut-offs for deficiency.

Did these researchers claim that milk will stave off dementia? Well, let’s look at their study. The researchers are Drs A David Smith from Oxford University and Helga Refsum, from the University of Oslo, who first presented their findings at the symposium "Is It Time for Mandatory Vitamin B-12 Fortification in Flour?" held in San Diego in April 2008.

There is a known association between vitamin B12 deficiency and cognitive deficits. It is possible that this relationship is due to brain shrinkage (atrophy) and damage to the brain’s white matter? Both of these pathologies are associated with low levels of Vitamin B12.

One of the ways of evaluating whether or not a person has sufficient stores of vitamin B12 is by examining levels of holotranscobalamin and methylmalonic acid in the blood. Holotranscobalamin is a vitamin B12 carrier protein (a special type of protein that carries specific substances across cell membranes), and methylmalonic acid is a substance produced when proteins in the body break down.

Drs Smith and Refsum set out to determine whether cognition in the elderly may also be adversely affected in cases where the concentrations of vitamin B-12 in the blood are within the normal range, but at the lower end. They reviewed the evidence for such an association by studying the results of intervention trials. They concluded that the intervention trials that had been conducted to date were too inadequately designed to be able to test whether cognition in the elderly was diminished by the lower, but still normal, levels of vitamin B12.

Drs Smith and Refsum recommend that until these associations are better understood, the elderly should be encouraged to eat diets rich in vitamin B12 so that their vitamin B12 levels stay in the good, rather than adequate, range.

References: Smith AD and Helga Refsum H .2009. Vitamin B-12 and cognition in the elderly. American Journal of Clinical Nutrition 89: 707S-711S. First published December 30, 2008.

News story: Milk could help prevent Alzheimer’s disease. TelegraphUK 28 February 2009

This news story and study have also been reviewed by NHS Knowledge Services

No comments:

Post a Comment

Alzheimer's Australia NSW

Alzheimer's Australia NSW
Alzheimer's Australia NSW

Latest headlines from Library News

Library News

Total Pageviews