Observatory

Viagra as Diet Pill? One Day, Perhaps

By DOUGLAS QUENQUA

Published: January 28, 2013

New evidence suggests that the erectile-dysfunction drug Viagra might have another use: helping burn away excess fat.

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Chris Gash

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The drug, generically known as sildenafil, helped convert undesirable white fat cells to energy-burning beige fat cells in laboratory mice, researchers at the University of Bonn in Germany report in The Journal of the Federation of American Societies for Experimental Biology.

It was already known that mice fed Viagra became less prone to obesity when fed a high-fat diet. What was not clear was why.

Dr. Alexander Pfeifer, director of the university’s Institute for Pharmacology and Toxicology, said he already had some clues: Viagra works by preventing the degradation of the intercellular messenger cGMP. Dr. Pfeifer has long been testing the effects of cGMP on fat cells.

So he fed the drug to mice for seven days and monitored their fat cells. As it turned out, the troublesome white fat cells, which are associated with human problems like the dreaded spare tire, were being converted to the beneficial type of fat cells at a higher rate than usual. Dr. Pfeifer called the results “very promising.”

Still, he cautions against taking the drug purely for dieting purposes. “The idea to have one pill and then obesity goes away, that is a dream, but not easy to come by,” he said. “What we are up to is basic research in mice. This pill is approved by the F.D.A. for a particular purpose for a reason.”