Meanwhile, Sears attacked Ornish's plan, charging that patients on his diet had died of heart attacks. And Glickman told reporters that he personally would be unable to adhere to a vegetarian regimen.
Robin Woo, PhD, deputy director of Georgetown University's Center for Food and Nutrition Policy, tells WebMD, "The [Atkins] low-carb, high-protein diet is excellent for the early management and treatment of some diabetes conditions. The Ornish diet, with the very low fat, is very good for some problems with [hardening of the arteries] and some of the cardiovascular conditions [such as heart disease and stroke]."
But Woo says, "The unbiased academic would say that none of those diets are ideal. They are for diseased states. They're not good for the long haul. We have to remember that we're omnivores, that we should have balanced eating."
Ayoob had a similar view, saying that "the real issue is long-term weight management," with research telling us that "diets don't work." Any diet would work in the short-term, he said, as long as it cut calories.
The other diet gurus proposed varying plans. According to Bethea, co-creator of a low-sugar diet, eaters should not drink water with meals and should avoid potatoes, beets, corn, and carrots. But under Sears' "zone" approach, individuals should focus on eating fruits, vegetables, and low-fat proteins.
McDougall, supporter of a low-fat, starch-based diet, maintained that both plans were "semi-starvation" approaches, because they were too complex and would leave people hungry.
The diet program kings agreed on relatively little. But their consensus areas included that water and physical activity are crucial to weight loss and health, that Americans should eat less refined and processed food, that smaller meals throughout the day are best, and that Americans should generally eat less food.
Woo tells WebMD, "The message is moderation in everything. Avoid taking intensive saturated fats and fatty acids. Make sure that you're positive in your eating habits, that you get good variety, that you eat plenty of vegetables and fruits, and that you get enough protein and calcium."
After their debate, the pack of diet gurus completed their day like Washington politicians might -- by smiling and clustering together for an official photo with Glickman.