There's a big question being explored right now about the intersection of health and social media: Does the tracking and sharing of personal fitness and diet data motivate us to get, and stay, healthy

A host of Web sites and mobile apps are banking on the answer being yes. FitDay provides a free diet journal' Daily Burn offers logs to track diet, exercise, and weight' an Awareness app promises to upgrade one's mental software' and dozens of other sites and apps cater to specific types of diets, exercises, and desired outcomes.

So the just-launched Humana fit social network, designed to help users live healthier, more active lives, is going to have to offer some pretty stellar features to stand out.

Humana fit is the brainchild of health benefits company Humana and health software app developer MapMyFitness, which after launching in 2006 boasts its own social network of about 3 million users.

Soft-launched to employees a few weeks ago, Humana fit boasts a wide range of features, including an online nutrition center, apps for mapping daily activities (iPhone, Android, BlackBerry), and a social network for sharing the minutiae of one's bodily health.

But the Web site is all over the place, with tabs ranging from routes and workouts to nutrition and community. Even if it turns out to be true that tracking and sharing helps motivate people to get and stay healthy, another important question looms: cover all aspects of health and fitness, or home in on a specific area of interest Go big, or go niche

Humana fit is clearly banking on going big. We'll keep an eye on whether it has found the winning formula.