Weight loss in a pill. It's the weight loss equivalent of the fountain of youth ... and just as elusive.

The major pharmaceutical company, Merck, has been in clinical trials for an anti-obesity drug called taranabant. But Merck recently announced that it was halting development of taranabant because of side effects. In certain doses, the drug was effective in helping patients lose significant amounts of weight. But there was an adverse side effect ... those taking the drug had an increased risk of psychiatric events. It's not clear from the article what exact psychiatric events were being experienced.

While the side effects of this pill are obviously extreme, it's not the first attempt at a weight loss pill that comes up short. While it would be nice to cure obesity with a quick fix, the old tried and true method of eating right and being more active is still the best bet.