Would adopting the diet our caveman ancestors supposedly ate allow modern-day Americans live longer, healthier lives?
Proponents of the Paleo diet (for Paleolithic) say that meals packed with fresh fruits and vegetables and heavy doses of lean (preferably wild) meat, fish and seafood will "swiftly improve your disease symptoms" if you have
, high cholesterol, Type 2
Not allowed are dairy, grains and legumes (beans, peas and lentils) because these were a late entry to the human palate, appearing about 12,000 years ago, and aren't foods to which we're "genetically adapted."
While the diet has fans — the recently released "Paleo Diet Cookbook" is fourth in a series of books written or co-written by Dr. Loren Cordain, a Colorado State University professor — dietitians argue that eliminating entire food groups is a mistake.
In particular, whole grains and low and nonfat dairy are inexpensive sources of nutrients that are essential to good health. They point to the
, which emphasizes grains, along with fruits, vegetables, fish, lean dairy and limited amounts of meat, as a proven way to decrease the risk of certain cancers and heart disease.
The problem with the American diet is excess, said Dr. Keith Ayoob, a pediatric nutritionist at New York's
College of Medicine.
"Do I want to see people eating a huge plate of pasta and nothing else? No," he said. "I want to see a reasonable portion with some lean meat and vegetables." Ayoob cites "the rice bowl" as an ideal meal: one cup of rice, two cups of vegetables and three ounces of lean meat in one bowl.
Dr. Joanne Slavin helped devise the 2010 Dietary Guidelines for Americans.
"Grains are really cheap, and for the average teenage boy it would cost a fortune to do this (Paleo) diet," said the food and nutrition professor at University of Minnesota. "Animals are a really inefficient way to get calories, and you don't need that much protein."
Ayoob argues that there's "a mountain of evidence for eating low-fat and fat-free dairy. People who eat dairy have better bone density, they're more likely to be normal weight … plus it's a great source of
and vitamin D."
Also, said Ayoob, people who eat grains enriched with
have reduced risk of neural tube defects, including
. Fortified grains "are cheap and there's no downside," he said.
Eliminating beans is another bone of contention. They're a cheap source of protein and have so many good qualities that it would be foolish to give them up, said Joan Salge Blake, a Boston-based dietitian and spokeswoman for the American Dietetic Association.
"Americans are only coming in at 14 grams of fiber, and we need 25 to 30," she said. "Beans are a great way to add fiber and protein at the salad bar and in pasta dishes."
Foraging folks have no set menu
The basic premise of the Paleo diet may be flawed too. Anthropologists say we don't know what Paleolithic man and woman survived on, and they most likely ate whatever was available.