The Paleo Diet: Your Definitive Guide To Eating Like A Caveman

You've probably heard the old health saying, "Don't eat it if your grandmother wouldn't recognize it." The idea being: toss the chemical-laden modern marvels in favor of natural, unprocessed foods for better health.

The paleo diet takes things a couple of generations (OK, a lot of generations) further.

Named for the Paleolithic Era (the period ranging from 2.5 million to 10,000 years ago), the paleo diet consists of the food groups that were available to our hunter-gatherer ancestors and it forgoes many of our relatively modern agricultural comforts.

Several studies suggest that it touts some major health benefits, too, including weight loss1 and prevention of chronic diseases2.

Whether you choose to go full-on caveman and follow a strict paleo diet or just cut back on processed foods, there's a lot to be learned from how our ancient ancestors ate.

We've improved on a lot of things since our cave-dwelling days, but cavemen may have had the whole "healthy diet" thing figured out.

But what exactly does it mean to eat like a caveman?

Essentially, the paleo diet rules dictate that you can eat no grains, no dairy, no soy or other legumes, no refined sugars, and obviously nothing highly processed that contains any of those ingredients. Even white potatoes are off limits, depending on how strictly you follow the plan.

First popularized by Loren Cordain, Ph.D. in his book The Paleo Diet, this way of eating is currently followed by about 7% of Americans. Everyone from LeBron James to actor Matthew McConaughey has reportedly dabbled with this caveman-inspired diet. With meal kit delivery companies offering paleo diet plans and grocery stores stocking shelves full of paleo snacks, it has never been easier to eat like a caveman.

So, why ditch foods that are typically considered healthy like whole grains and legumes? Many people who subscribe to the paleo diet believe we did not actually evolve to eat many of the foods in our "modern" diet. Agriculture, after all, is a relatively new development for our species, and for millions of years, our ancestors survived by eating only what they could scour from the earth.

If there is one thing nutrition experts agree on it's that the typical American diet is not healthy.

More than 73% of U.S. adults4 are overweight or obese, and at least four of the top 10 leading causes of death have been linked to poor diet—but it hasn't always been this way. For millions of years, humans were much more likely to die of a communicable disease than a chronic disease.

Our cave-dwelling ancestors weren't dying of diabetes or heart disease. The main goal of the paleo diet and paleo lifestyle is to prevent these modern chronic diseases by nourishing our bodies with the fuel that helped us survive, and thrive, for almost all of human history.

The paleo diet goes back to basics, promoting an unprocessed, whole-foods-based diet rich in protein, fiber, and good fats.

So, what exactly can you expect if you swap your modern diet in favor of a diet fit for a caveman? For starters, you'll probably lose some weight. 

Although weight loss is not the primary goal of the paleo diet, it is a welcome side effect. Studies have confirmed that the paleo diet can be more effective5 than conventional low-fat diets for short term weight loss. This may be due to the elimination of most added sugars and processed foods that tend to be loaded with calories and fat. 

Notably, it seems the paleo diet is especially effective for reducing belly fat6, the most harmful kind of fat, that can lead to diabetes and other weight-related hormonal issues. But does the paleo diet deliver on its proposed chronic disease-fighting promises? You bet.

Although the paleo diet in modern times is fairly new, meaning there are limited long-term studies, it has been shown to reduce risk factors for many common chronic health conditions.

In one small study7 comparing the paleo diet to the Mediterranean diet (often considered the optimal way of eating), in patients with heart disease, those following the paleo diet saw significantly greater improvements in blood glucose tolerance. Meaning: The paleo diet may help reduce the risk of developing diabetes.

Another study8 found that the paleo diet can be as effective as the Mediterranean diet for reducing signs of inflammation and oxidative stress, important biomarkers for cancer and chronic disease. 

And when it comes to heart health, the paleo diet came out on top5 for improving triglycerides, systolic blood pressure, and HDL cholesterol as compared to a diet based on our current dietary guidelines.

Coffee, tea, and herbal tea are also allowed, and you should also drink plenty of water.

Although there are many health benefits to following this way of eating, functional medicine practitioner Mark Hyman, M.D., warns that "some use the paleo philosophy as an excuse to eat too much meat and too few plant-based foods."

Instead, he advocates a healthy mix of a plant-based vegan diet and a back-to-basics paleo diet, called the pegan diet. Essentially, prioritizing fiber-rich antioxidant-packed vegetables while ditching processed grains and added sugar, can help ensure you reap all of the anti-inflammatory disease-fighting powers of this ancient diet.

Another thing to watch out for: paleo flu. Also known as the "low-carb flu" and the "keto flu," some of the symptoms you can expect from transitioning to a refined-grain-free diet include headaches, fatigue, and brain fog. 

As your body adjusts to using protein and fat as its main fuel sources rather than a steady stream of glucose from grains and refined carbs, you may experience some of these not-so-great side effects. 

However, unlike the keto diet, you don't necessarily have to go low-carb on paleo. Just be sure to consume your carbs from healthy, non-grain sources such as squash, sweet potato, or any type of fruit.

Staying hydrated can also support your body's detoxification mechanisms and help ward off these symptoms.

It feels like there are a million different eating styles to choose from these days (paleo, keto, vegan, and intermittent fasting, just to name few), and what works for one person may not necessarily work for another.