Chicago (ddp). An excess of B vitamins accelerates the progression of kidney disease in diabetics. This conclusion has come a Canadian research team and explicitly warns patients with so-called diabetic nephropathy of a vitamin B therapy so far believed, that she could slow down the deterioration of kidney functions. In their study, scientists had investigated 238 diabetics with kidney disease who received vitamin B tablets daily. Here they found not only a deterioration of the renal functions, but «JAMA» (vol. 303, no. 16, p. 1603) report also a doubling of risk for strokes and heart and vascular diseases, Andrew House from the University of Western Ontario in London, Ontario and his colleagues in the journal.

Longtime diabetics often develop kidney disease, which can ultimately lead to a failure of vital organs of the filter. Several studies had shown a correlation between the creation of these diabetic nephropathy and an increased concentration on so-called Homocysteinen in the blood. Because B vitamins can reduce the levels of these amino acids, was been propagated, that regular vitamin gifts could prevent the kidney damage or slow its progression. These recommendations were based mainly on the analysis of Homocysteinspiegels in urine samples of diabetics, where after a vitamin B therapy in fact a decline was observed.

House and his team examined now but also the glomerular filtration rate, the information on the functioning of the kidneys: determined the rate of 238 patients with diabetic nephropathy, which they have an average 36 months daily administered a placebo or contained a tablet, the 2.5 milligrams of folic acid (vitamin B9), 25 milligrams vitamin B6 as well as 1 milligram of vitamin B12. In addition, they saw from how many strokes suffered the patients in the different groups and how many heart and vascular diseases developed them.

Expectations of researchers to the patients who received additional B vitamins, would need to achieve better results in all respects than the placebo group – but the opposite was the case. Sank in turn of the Homocysteinspiegel in the urine of the vitamin group although their kidney function compared to the placebo group worsened significantly, were also additional complications encountered much more often such as stroke or heart and vascular diseases. According to the scientists, a vitamin B therapy in people with normal kidney function may be positive, because it can excrete excess vitamins with urine. Nierenkranke be to not or not in the normal ground capable of producing possibly the observed effects would be. Therefore they should be given as is now clear evidence, vitamin B no high doses. It must be sought now for other ways to reduce the Homocysteinspiegel.