Last week the FDA approved Arena Pharmaceuticals Inc.’s pill Belviq to treat obesity when combined with healthy eating and weight loss, after denying it in 2010 because of concerns over tumors that developed during animal trials of the drug. Now, however, the FDA cited three studies of nearly 8,000 overweight and obese patients before giving approval.

Since two-thirds of Americans are overweight or obese, many are hopeful that the pill will help fight obesity in new ways. With a positive response reported by ABC News and CBS News, Americans might recall other weight-loss drugs that were hailed as a magic bullet but proved to be more hazardous than healthy. In fact, Belviq works in a similar way to the fen-phen appetite-suppression drug combination, which was pulled from the market in 1997 because of a link to fatal heart problems. However, Belviq convinces people that they feel full after eating less food, like the more invasive lap band surgery.

Bottom line: Although the long-term effects of the drug are unknown, it is a huge breakthrough in the world of weight-loss medicine. We hope it helps fight the obesity epidemic.