New Evidence Alli May Actually Promote Weight Gain

Despite a huge marketing push and tons of overly-optimistic press, plenty of skepticism was raised at the time the prescription anti-obesity drug Orlistat was released in a lower-dose over-the-counter version called Alli. Alli interferes with a key enzyme (lipase) involved in the digestion of fat and can reduce the amount of fat calories absorbed from food by a modest amount, around 30%.

Skeptics were quick to point out that, in terms of dietary factors, most people aren’t obese because they eat too much fat, they’re obese because they eat too much sugar and too many refined carbohydrates. So reducing the amount of fat calories by this modest amount isn’t likely to do much, and it comes as no surprise that Alli has yet to live up to the hype and promise that surrounded its introduction.

And Alli’s notorious side-effect profile has attracted almost as much attention as the drug itself.

A new human study adds to these concerns about the effectiveness of Orlistat.

The study showed that Orlistat tended to raise appetites overall while disrupting the balance of biochemicals and hormones (grehlin, CCK) associated with fat storage, appetite, and the sense of fullness and satiety that normally follow a meal. By increasing appetite and interfering with the feedback mechanisms that signal us to stop eating because we’re full, Orlistat may be ineffective for many obese people even to the point of encouraging further weight gain.

Link: http://www.ncbi.nlm.nih.gov/pubmed/18647814