Tech-savvy eaters have come to the defense of stone age eating habits after U.S. News and World Report "Best Diets" ranked the Paleo diet dead last in its best overall weight loss category.
For the rankings, 22 experts, including nutritionists, dietitians, cardiologists and diabetologists, reviewed 20 popular diet profiles that were developed by reporters and editors at U.S. News and World Report.
But now, proponents of the Paleolithic diet are defending their research and the diet by saying eating like a caveman may be the healthiest thing you ever do.
The eating regimen consists of fruits, vegetables, lean meats, fish and nuts. The dieters are told to avoid salt, sugar, milk and grains, as humans in the Stone Age time did not have access to such foods.
After the rankings giant posted its results two weeks ago, Loren Cordain, a leading voice on Paleolithic diets and professor of health and exercise at Colorado State University, posted an online rebuttal, noting five clinical studies that found the Paleo diet lowered blood pressure and cholesterol and improved insulin resistance. The trials specifically related to the Caveman Diet were small (none of them involved more than 30 people), but Cordain's blog post gained the attention of Paleo diet followers, who then also went online to personally vouch for the eating style.
On the U.S. News and World Report rankings Paleo diet page, more than 3,000 people said the diet had worked for them, while 80 said it did not. Compare that to the No. 1-ranked diet, Weight Watchers, in which 1,883 people said the diet worked for them and nearly 800 people said it did not.
"Whoever was the writer of these reviews had not read the science behind the Paleo diet," Cordain said. "I personally don't like evaluating something and have huge bits of evidence that weren't examined. That's bad science.
"There have now been five clinical trials showing that this diet is a powerful way to normalize health and well-being," Cordain said.
But U.S. News and World Report stood by its ratings.
"For the Paleo diet, additional evidence is needed to show conclusively whether or not it is as effective as some people hypothesize," said Ben Harder, general manager of Health & Science at U.S. News & World Report. "The most relevant studies have been small, as our published review of the Paleo diet indicates. We hope researchers will publish more -- and larger -- studies on the Paleo diet so that health experts, including our expert panel, have more evidence to consider in the future."
Cordain said the science behind the Caveman diet is analyzed by "evolution through natural selection." While he is put off by the term "caveman diet," because it sounds silly, sexist, and makes people thinking of Fred Flintstone and Barney Rubble swinging clubs around, there is an important scientific explanation behind the eating style.
"The environment has sped way ahead of what our genes are adapted to," he said. "We are a good field animal, we're good when we're outdoors and expending energy to get energy, but in the modern world, we've broken that link.
"We're stone-agers misplaced in space-age time."