Religion, it is said, nourishes the soul. Now there is a movement that uses religion as a path to a better body -- a burgeoning Christian diet industry that takes a faith-based approach to fighting fat.
Dr. Don Colbert, an evangelical Christian and Florida family doctor, read something that shocked him: Obseity, a 1998 Purdue University study concluded, was associated with strong religious participation. The firmer your faith, the study suggested, the flabbier your belly.
"Christians usually don't drink, they don't smoke, they don't use drugs and they don't party," Colbert said. "So as a result, what they'll do is simply eat."
In his book, "What Would Jesus Eat?," Colbert has made it his mission to promote a lean, Mediterranean-style diet that eliminates foods prohibited in the Bible, such as pork.
He says it works better than secular diets because religious dieters constantly connect food choices to their deepest beliefs by asking questions like: "Should I eat this food? Would Jesus eat this food? Is this food good for me?"
The Weigh Down Diet tells overeaters like Thea Wilson to fill any voids in their lives with Jesus.
"The moment that I decided when I'm sad I'm going to seek help from God instead of Lay's potato chips," Wilson said.
These programs combine two great American enthusiasms -- faith and dieting. But medical experts warn there are some false diet prophets out there.
"Sometimes they persuade people to follow their diet instead of getting care that they need," said Dr. Stephen Barrett. "Diets should be based on nutritional science rather than revelation."
George Malkmus says his Hallelujah Diet comes from the book of Genesis. It's almost entirely raw fruits and vegetables, containing no animals or animal products.
He says it cured his colon cancer.
"Within a year my baseball-size tumor was gone, as were all the physical problems I was experiencing," he said.
Another diet guru, Jordan Rubin, says his Maker's Diet, taken from the book of Leviticus, cured his Crohn's disease.
But the Food and Drug Administration warned that his previous book pushed products "not generally recognized as safe and effective."
Nutritionists say some faith-based diets are effective. But as with all prescriptions for better health, buyer -- or believer -- beware.