Recently I caught a couple episodes of The Truth About Food on the Discovery Health Channel. It is a show where they conduct experiments based on full studies that have been done in the past. All the studies have something to do with food and how it affects your body. They start with a question like "Do you really have to drink 2 quarts of water every day?" Then they illustrate the original study on a smaller scale with a few volunteers.
If I've made the show sound dry, it isn't. It reminds me of the British show Brainiac without the sexually suggestive content. There are interviews with the volunteers so that you can hear how they are feeling while they are going through the experiments. The episode where they took six hard-partying young women and put them on a detox diet for a week was fun and informative. In fact, I learned a lot from several of the experiments.
I would suggest watching this show if you can find it. On my DirecTV guide, it was mislabeled; I only caught it because I thought a plastic surgery show was airing during that hour. Discovery Health has an episode schedule on their site, so that may be more helpful. There was also a British version of this show airing on BBC Two, but I can't tell from the website if it is still on the air.