When it comes to what we eat, Americans have long chosen the path of least resistance. It’s been that way ever since the advent of fast food chains, microwave ovens, and the highly processed, pre-packaged convenience foods found on modern grocery store shelves, and the trend has had disastrous effects on our nation’s overall health and well-being. With more than one-third of our citizens overweight, we lead the world in obesity levels, and we shell out more money to treat preventable ailments — diabetes and heart disease just to name a few — than any other nation on earth. But our troubling health epidemic hasn’t gone unnoticed or untreated. Public awareness about our collective weight issue is at an all-time high, and the trendy diets are more prevalent than ever.One of the most popular is the “Paleo” or “Cave Man Diet.” Based on the premise that our bodies are biologically adapted to consume only that which appeared on the menus of our cave-dwelling, prehistoric ancestors, the Paleo plan promotes lean meat consumption and avoiding any modern convenience food that wasn’t hunted or gathered by nomads living from 2.6 million years ago to 10,000 B.C. Paleo advocates claim that only by abandoning agriculturally based diets, which are “out of sync with human biology,” can we begin to live fuller, healthier, longer lives. Many even go so far as to suggest the elimination of legumes and other veggies like tomatoes and eggplant. The number one tenet in the paleo diet’s detailed mission statement is an increase in daily protein intake. According to the diet’s creator and founder of the modern paleo movement, Dr. Loren Cordain, augmented meat consumption is afforded such high priority because that is exactly the way that our ancient Paleolithic ancestors would have had it. “In our laboratories we looked at 229 hunter gatherer societies,” Cordain said in a recent television interview, “and data from our findings suggests that the average meat intake was about 55% of calories.”“Paleo allows me to remain healthy and happy,” Cordain says, “and I’m truly gratified when I hear anecdotal evidence about the way in which it has changed people’s lives for the better.” It is Cordain’s finding that 55% of the Paleolithic diet was based in meat consumption that certain qualified individuals take issue with when critiquing the Paleo diet. One such individual is Harvard evolutionary biologist Daniel Lieberman, who argues that gathering provided far more calories than hunting for our paleo ancestors. “There is a lot of good information to be gleaned from the dietary habits of Paleolithic era hominids,” Lieberman told me. “But it’s important that we critically evaluate these habits and apply only that which makes good, sound biological sense. Just because Paleolithic people may have eaten something doesn’t necessarily mean it is a healthy option for the modern human.”He went on to explain: “There is no one paleo diet. These people existed for millions of years and inhabited many different corners of the globe. Trying to pinpoint one homogenous Paleolithic diet is neither feasible nor rooted in evolutionary study.” According to Lieberman, early humans used persistence hunting—literally chasing animals to death—as a way to supplement their staple foods like foraged tubers, insects and other wild plants, but meat was more of a hard-earned luxury than an everyday menu item like many modern Paleo diet advocates often claim. Most Paleolithic humans couldn’t possibly ensure that their daily diet was made up of 55% lean meats because, on the rare occasion that they actually ate meat, they literally had to chase it to death. Even when successful, they were likely forced to share the kill with other members of a growing tribe.Bipedal hominids who lived during this time frame are believed to have eaten anything and everything they could—including insects, scavenged entrails, and dozens of varieties of fruits, nuts, seeds, and tubers. Rather than emphasizing meat, a true Paleo diet should probably place more emphasis on the seasonality and wide variety of natural, unprocessed food sources, mainly from plants. This isn’t to say that we modern humans can’t derive valuable lessons from the lifestyles and culinary habits of our ancient ancestors. For instance, cutting as many processed foods from your diet as you possibly can is always a good thing, and implementing locally sourced, native plant foods will almost certainly benefit your health.But you should probably stop short of banishing legumes and tomatoes while freely consuming heaping portions of free-range bacon and porterhouse steaks.