DUBLIN, IRELAND. Endothelial dysfunction is an established precursor for atherosclerosis and has also been implicated in diabetes and abnormal cholesterol levels. Endothelial dysfunction, in turn, is a disorder of the lining of the blood vessels manifesting itself by reduced arterial blood flow and greater platelet activity. It is believed that impaired synthesis of nitrogen oxide (NO), which acts to relax blood vessel linings, is the major cause of endothelial dysfunction.
Endothelial dysfunction is particularly rampant among smokers and is no doubt an important cause of the cardiovascular disease accompanying smoking. Medical doctors at Dublin's Beaumont Hospital recently reported that supplementation with vitamin C and in particular, the amino acid, taurine markedly reduces endothelial dysfunction in young smokers.
Their clinical trial involved 15 healthy smokers (aged 20 to 37 years) and 15 healthy controls. The extent of
endothelial dysfunction was measured in all participants at the start of the trial and after 5 days of
supplementation. Flow-mediated dilation (FMD) of the brachial artery was determined through ultrasound
images. FMD is a direct indication of endothelial dysfunction. Vitamin-C supplementation (2000 mg/day)
significantly increased FMD in smokers, but did not bring it to the level of the controls. Supplementation with
taurine (1.5 grams/day), on the other hand, brought FMD levels in smokers back to the level of the controls,
thus essentially eliminating the endothelial dysfunction. The researchers also performed test tube (in vitro)
experiments that clearly showed that taurine supplementation restores normal NO production. They
conclude that taurine has a beneficial effect on macrovascular endothelial function and may be useful in
dealing with problems caused by high cholesterol and triglyceride levels.