A cross-sectional study with 1,205 people found that higher levels of pyridoxal-5'-phosphate (PLP), the active form of vitamin B6, were linked to lower levels of C-reactive protein (CRP), a marker of inflammation, as well as lower levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker for oxidative stress, both of which are related to heart disease risk.

CRP is produced in the liver and is a known marker for inflammation. Increased levels of CRP are a good predictor for the onset of both type-2 diabetes and cardiovascular disease. CVD causes almost 50 per cent of deaths in Europe, and is reported to cost the EU economy an estimated €169 billion ($202 billion) per year.

Researchers from the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University report their findings in the American Journal of Clinical Nutrition​.

“Our data suggest that vitamin B-6 may influence cardiovascular disease risk through mechanisms other than [reduction of the amino acid] homocysteine and support the notion that nutritional status may influence the health disparities present in this population,”​ wrote the researchers, led by Jian Shen.

Study details​

Shen and co-workers measured levels of PLP, CRP, and 8-OHdG in 1,205 Puerto Rican adults aged between 45 and 75 and living in Massachusetts.

Results showed a strong dose-dependent relationship between PLP levels and CRP levels, with the highest PLP levels associated with CRP levels almost 50 per cent lower than low PLP levels.

Furthermore, the highest average levels of PLP were associated with 8-OHdG concentrations of 108 nanograms per milligram, compared to 124 ng/mg for low PLP levels.

The associations were observed even after the researchers took into account homocysteine levels.

It is not the first time that PLP levels have been linked to CRP levels. A Harvard study reported last year that PLP levels were slightly inversely correlated with blood levels of CRP, and may also reduce the risk of colorectal cancer by 50 per cent (Cancer Epidemiology, Biomarkers & Prevention​, Vol. 18, pp. 1197-1202).

Source: American Journal of Clinical Nutrition​

February 2010, Volume 91, Number 2, Pages 337-342, doi:10.3945/ajcn.2009.28571

“Association of vitamin B-6 status with inflammation, oxidative stress, and chronic inflammatory conditions: the Boston Puerto Rican Health Study”​

Authors: J. Shen, C-Q. Lai, J. Mattei, J.M. Ordovas, K.L. Tucker