Paleo Rules: The Science Behind the Diet

July 16, 2019

Meat, fish, nuts and vegetables spread out on a table
Jonathan Thompson

What is the paleo diet? What sort of foods does it include or exclude? Should you give this popular diet a try?

Guidelines

Also known as the Paleolithic diet or (rarely) the caveman diet, the general idea of eating "paleo" is to mimic the diet of hunter-gatherers as it was over 10,000 years ago. In large part, this diet is based on the concept that the human body has not evolved to eat any of the foods that have been developed after the agricultural revolution. Fans of this diet will tell you that this means sticking to lean, protein-rich foods like grass-fed meat and eggs, with a heavy emphasis on fruits and vegetables. Most grains are to be avoided, as are dairy, potatoes, legumes and any processed or refined foods.

It's worth noting, however, that there is some disagreement regarding this list of dietary do's and don'ts. Some adherents, for example, allow seeds while others do not. There's also some dispute within the paleo community about exactly how our ancestors divided up their macronutrients. The typical recommendation is that your diet should consist of 40% protein, 40% fat and only 20% carbohydrates. For the sake of comparison, most health organizations recommend a diet of 20% protein, 30% fat and 50% carbs.

The Benefits

The idea that people should limit their intake of refined foods and stick to whole, natural options with healthy fats is nothing new. Even better, there is a substantial amount of research to back-up this concept. This general dietary structure has been shown to increase cardiovascular health and aid in weight loss while decreasing the risk of diabetes and certain cancers.

A well-executed Paleolithic diet also focuses heavily on locally-grown, organic foods, which have a range of benefits. Overall, the Paleolithic diet seems like a relatively good option for those looking to lose weight and enhance their well-being.

Negative Aspects

Upon closer inspection, however, the Paleolithic diet usually doesn't hold up very well. The inconsistencies and internal disagreements mentioned above make the diet somewhat hard to follow; there are various versions all claiming to be the right one. Regardless of which version you follow, the rules are still fairly restrictive. Not only does this tend to make any diet hard to adhere to, but it can also lead to nutrient deficiencies. In fact, many people on the Paleolithic diet end up taking vitamin D and calcium supplements.

Though studies back the use of high-protein diets for weight loss, more recent research has lead to doubt about the overall health impact of these strategies. Individuals who have certain conditions that affect the kidneys and other organs are usually advised to avoid high-protein diets. In fact, many experts feel like the lack of research into the diet should be of concern to even healthy individuals. Adding to the confusion, a recent study suggests that some Paleolithic humans did, in fact, eat bread, which would contradict central teachings held by supporters of the paleo diet.

But, by far, the biggest criticism of this diet is that the whole concept behind it — eating like Paleolithic humans — is flawed. Humans in Europe ate very differently from their counterparts in Africa; there wasn't a universal Paleolithic diet. Also, many foods eaten by humans during that time period no longer exist, and a lot of foods eaten now did not exist then. So, really a true Paleolithic diet is an impossibility.

Ultimately, there is no clear answer to the question, "what is the paleo diet?" Generally speaking, the idea is to eat the way that humanity's ancestors supposedly did before the advent of agriculture. Unfortunately, this seems to be based on an oversimplification and the diet has some fairly significant flaws.

Sign Up to Receive Our Newsletter & Get the Best Ergonomic Tips