The cardiovascular benefits of folate and folic acid, the synthetic bioavailable form, have been reported previously, and are linked to the B vitamin’s effects on homocysteine levels, an amino acid that at high levels has been linked to an increase in the risk of heart disease.
The new study, led by Sai Wang Seto from the Chinese University of Hong Kong, found that diabetic mice fed a daily folic acid supplement equivalent to 5 milligrams per day for a 70 kg human, led to a reversal in the dysfunction occurring in the lining of blood vessels (endothelial dysfunction), compared to a lower dose of the micronutrient.
“Folic acid consumption may probably make it a beneficial addition to [improve] vascular disorders/complications associated with diabetes mellitus,” wrote the researchers in The Journal of Nutritional Biochemistry.
An estimated 19 million people are affected by diabetes in the EU 25, equal to four per cent of the total population. This figure is projected to increase to 26 million by 2030.
In the US, there are almost 24 million people with diabetes, equal to 8 per cent of the population. The total costs are thought to be as much as $174 billion, with $116 billion being direct costs from medication, according to 2005-2007 American Diabetes Association figures.
For the new study, Seto and co-workers used diabetic mice and fed them daily supplements of folic acid. After one month, the observed that mice not fed the supplements experienced blunted vascular relaxation, while the supplements improved this process.
The improvements were linked to a protein pathway that involves eNOS – a molecule that promotes dilation of the blood vessels and prevents clotting – and Akt – a signaling protein linked to the regulation of the insulin and insulin-like growth factor (IGF-1) pathways.
Folate and heart health
Epidemiological studies have linked increased blood levels of the amino acid homocysteine to an increased risk of cardiovascular disease (CVD). It has been suggested that by lowering the levels of homocysteine in the blood with B-vitamins, people could cut the risk of CVD.
Source: The Journal of Nutritional Biochemistry
Published online ahead of print, doi: 10.1016/j.jnutbio.2009.06.015
“Folic acid consumption reduces resistin level and restores blunted acetylcholine-induced aortic relaxation in obese/diabetic mice”
Authors: S.W. Seto, T.Y. Lam, P.M.Y. Or, W.Y.W. Lee, A.L.S. Au, et al.