People with type 1 or type 2 diabetes have about three-quarters less thiamine (vitamin B) in their blood than people without diabetes, according to new research out of Warwick Medical School in England. And it's not because they're not eating enough thiamine.

They run short because when the thiamine passes through their kidneys, it's not reabsorbed back into the blood like it is in other people. Instead, it just goes straight out: kidney clearance of thiamine is increased 24-fold in type 1 and 16-fold in type 2.

Oddly enough, this deficiency has never been noted before because researchers had been fooled by measuring an enzyme whose activity is usually reduced when thiamine levels are low. In people with diabetes, the enzyme's activity was still normal, causing earlier researchers to assume that thiamine levels were also normal.

And what are the unfortunate effects of this thiamine shortage? The low thiamine levels are linked to an increase in an inflammation marker related to microvascular and macrovascular complications. The marker reflects higher likelihood of problems in the endothelial cells that line the circulatory system and of chronic artery wall inflammation.

The researchers report that vitamin B has been shown to prevent vascular problems in previous studies. They estimate that because around forty percent of diabetic people develop vascular complications despite good blood glucose control, vitamin B supplementation could lead to as much as a forty percent decrease in those complications.

Although the currently recommended dietary intake of vitamin B is about 1 milligram, the study authors suggest that a supplement of about 100 milligrams might be of use. Don't act too fast, however, because they are calling for clinical trials to investigate the matter first.

Sources: Diabetologia, August 2007; Physorg.com; UK News