Lately, nutrition experts have been saying we should eat like people used to. They don't mean before microwave ovens, but rather like our ancestors did 10,000 years ago. In those days, the main problem with food was not overconsumption as it is today, but rather finding enough to prevent starvation. Our evolutionary ancestors solved this problem by storing fat quickly and easily to see them through periods of famine.
But like many important decisions in life, choosing a weight-loss plan is one you shouldn't make alone. Many fad diets are questionable, controversial, and may even be unhealthy. Before starting a weight-loss program, including the six listed here, talk to your doctor about whether your choice is right for you.
"Back then," quips weight-loss expert Dean Ornish, M.D., president of the Preventive Medicine Research Institute in Sausalito, Calif., "it was survival of the fattest."
Today we have essentially the same genetic makeup as our starvation-threatened ancestors, but the very fat-storage mechanism that saved them is killing us. According to anthropologists S. Eaton Boyd, Ph.D., Marjorie Shostak, Ph.D., and Melvin Konner, Ph.D., authors of The Paleolithic Prescription, we've become caught in a dietary time warp. Like Rip van Winkle, we've awakened in a world of high-fat fast foods that our bodies are genetically incapable of thriving on. The result? The fat-related chronic illnesses that are now our leading causes of death.
But like many important decisions in life, choosing a weight-loss plan is one you shouldn't make alone. Many fad diets are questionable, controversial, and may even be unhealthy. Before starting a weight-loss program, including the six listed here, talk to your doctor about whether your choice is right for you.
"Back then," quips weight-loss expert Dean Ornish, M.D., president of the Preventive Medicine Research Institute in Sausalito, Calif., "it was survival of the fattest."
Today we have essentially the same genetic makeup as our starvation-threatened ancestors, but the very fat-storage mechanism that saved them is killing us. According to anthropologists S. Eaton Boyd, Ph.D., Marjorie Shostak, Ph.D., and Melvin Konner, Ph.D., authors of The Paleolithic Prescription, we've become caught in a dietary time warp. Like Rip van Winkle, we've awakened in a world of high-fat fast foods that our bodies are genetically incapable of thriving on. The result? The fat-related chronic illnesses that are now our leading causes of death.
How should we eat? Like our Stone Age ancestors
Boyd is an expert on ancient diets, and Shostak and Konner lived for several years with the Kung tribe of the Kalahari Desert in southern Africa, one of the few remaining hunter-gatherer peoples on earth. Together the doctors pieced together what early humans ate: primarily plants -- nuts, fruits, beans, grains, and roots -- with some game meats.
But those meats were much different from ours. They contained only about 5% fat by weight, much less than our domesticated meat animals (30% fat). Overall, these experts contend, the human body evolved to consume a diet with no more than about 20% of the calories come from fat -- only about half as much fat as most Americans eat today.
Throughout most of human history, even after the arrival of civilization, agriculture, and industry, people continued to eat more or less as they were genetically programmed to do. In 1910, Americans ate a diet based on carbohydrates, with only about 20% of its calories coming from fat.
"They consumed more total calories than we do today," says Neil Barnard, M.D. -- author of Food for Life and president of the Physicians Committee for Responsible Medicine in Washington, D.C., a professional organization that promotes preventive medicine through nutrition -- "but far fewer from fat, and heart disease, cancer, diabetes, hypertension, and obesity were all rare."
Today, according to a recent report by the National Center for Health Statistics, American fat consumption averages 34% of total calories. That average is down slightly from 1978, when the figure was 36%, but averages can be misleading. Some Americans have cut way back on fats, but millions still consume at least twice as much fat as their great-grandparents did.
But those meats were much different from ours. They contained only about 5% fat by weight, much less than our domesticated meat animals (30% fat). Overall, these experts contend, the human body evolved to consume a diet with no more than about 20% of the calories come from fat -- only about half as much fat as most Americans eat today.
Throughout most of human history, even after the arrival of civilization, agriculture, and industry, people continued to eat more or less as they were genetically programmed to do. In 1910, Americans ate a diet based on carbohydrates, with only about 20% of its calories coming from fat.
"They consumed more total calories than we do today," says Neil Barnard, M.D. -- author of Food for Life and president of the Physicians Committee for Responsible Medicine in Washington, D.C., a professional organization that promotes preventive medicine through nutrition -- "but far fewer from fat, and heart disease, cancer, diabetes, hypertension, and obesity were all rare."
Today, according to a recent report by the National Center for Health Statistics, American fat consumption averages 34% of total calories. That average is down slightly from 1978, when the figure was 36%, but averages can be misleading. Some Americans have cut way back on fats, but millions still consume at least twice as much fat as their great-grandparents did.