The Motley Fool's health-care show Market Checkup focuses this week on obesity, one of America's largest health-care concerns. Recently classified as a disease, obesity leads to serious health problems, including diabetes, heart disease, and stroke. Currently 35% of adults in the U.S. are classified as obese, but more troubling, one out of three children is as well. All told, obesity adds $190 billion in medical costs to the system, but efforts to tackle this growing problem are increasing.

In this video, health-care analysts David Williamson and Max Macaluso discuss the third and often forgotten obesity-drug maker, Orexigen. This small-cap is stuck running an additional phase 3 trial for Contrave while its two competitors have made it to market. But given its prior positive FDA advisory committee vote and its small market cap, Orexigen may be the best speculative play of all obesity stocks. Watch and find out why.

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