New research shows concern that two popular weight loss drugs, Alli and Xenical, may cause liver damage. On Monday, August 24, 2009, the Food and Drug Administration (FDA) began investigating recent reports that these drugs may be causing liver damage in those who take them.

To date, there have been 30 reported cases of liver damage by those who take Alli, the only non-prescription weight loss drug the FDA has approved, and Xenical, its prescription counterpart. Of the 30 reports, 27 individuals have been hospitalized and six of them have experienced liver failure.

Both drugs are marketed by British drugmaker GlaxoSmithKline PLC, but Xenical is manufactured by pharmaceutical giant Roche.

A new study is suggesting that the diet drug Orlistat, more popularly known under its prescription name Xenical, doesn’t help people improve their eating habits. But it’s even being suggested that it has the opposite effect.

When Xenical works, it blocks the absorption of fat in the intestines. Users are advised to reduce their dietary fat intake, consuming no more than 30 percent of their calories from fat each day.

This is what The Diet Blog has to say:

A new study suggests the popular diet drug Orlistat… doesn’t inspire people to improve their diets, instead individuals popping Xenical are more likely to eat worse. How’s that for irony.