THE BLOG

The Pros and Cons of the Paleo Diet

09/17/2014 08:29 am ET | Updated Nov 17, 2014

You've probably heard about the Paleo diet; maybe you've even tried it. The "primal eating" trend is everywhere.

Paleo, of course, encourages us to eat like our ancient ancestors did.

The concept is this: Humans evolved on a diet very different from today's eating habits.

Therefore, the Paleo proponents argue, to be healthier, leaner, stronger and fitter, we must re-think our diet and remove some of the food groups we consider basic.

Promising everything from fat loss to more energy and clearer skin, Paleo certainly has appeal.

But what is Paleo really? Is it a diet worth trying?

Why "Paleo": The basic concept of eating primal

To understand Paleo thinking, we've got to go back in time. (My DeLorean is parked right outside.)

Let's have a quick look at what our ancestors ate:

  • 60 million years ago: Our oldest cousins, the earliest primates, ate a lot like, well, primates. They subsisted mainly on fruit, leaves, and insects.
  • 2.6 million years ago: Evolution at work! Humans started using tools and fire, and moved to a hunter-gatherer diet.
  • 10,000 years ago: At this point, "agriculture" had taken the world by storm.

Paleolithic humans definitely got some eating habits right. In general, they consumed:

  • three times more produce than the typical American,
  • more fiber,
  • more protein,
  • more omega-3 fatty acids,
  • more unsaturated fat,
  • more vitamins and minerals,
  • and much less saturated fat and sodium.

That said, Paleo fans tend to overlook the fact that hunter-gatherers were not models of pristine health. Paleolithic humans suffered from parasites, infectious diseases, and even atherosclerosis (hardening of the arteries).

The dangers of our modern diet

Fast forward to today. Our diet has changed significantly, and not necessarily for the better. For one thing, it contains far more processed, packaged and commercially-produced foods than ever.

Case in point: The top six calorie sources in the U.S. diet today are:

  • grain-based desserts (cake, cookies, etc.),
  • yeast breads,
  • chicken-based dishes (and you know that doesn't mean roast chicken),
  • sweetened beverages,
  • pizza,
  • and alcoholic drinks.

Yikes. Not only are these foods not ancestral, some of them could barely be called food.

Meanwhile, obesity, diabetes, and cardiovascular diseases have dramatically increased over the past 50 years.

The Paleo claim that our modern Western diet isn't healthy rings true. So what should we do to make it better?

According to Paleo: What to eat and what to avoid

Paleo fans suggest we return to the meat and produce-based diet of our past. Specifically, the Paleo dietary model encourages us to base our diets on the following foods:

  • animals (especially a "whole animal" approach, including organs, bone marrow, cartilage, and organs),
  • animal products (such as eggs or honey),
  • vegetables and fruits,
  • raw nuts and seeds,
  • and added fats (like coconut oil, avocado, butter, ghee).

Notice what's missing from the list? Paleo tells us to avoid grains (even "whole grains"), heavily processed oils (such as canola and soybean oil), and processed foods in general.

Legumes and dairy are typically off limits too, though some guidelines allow these foods as the Paleo diet continues to "evolve."

Should you stop eating grains and legumes?

We already know the above list of processed foods and treats aren't good for us -- but what about whole grains and legumes?

Let's tackle legumes first. Paleo people say we shouldn't eat legumes because of their high concentration of anti-nutrients like lectins or phytates. Supposedly that reduces their nutritional value to zilch.

Fortunately for bean fans, that's not true.

Research suggests that the benefits of legumes outweigh their anti-nutrient content. Cooking eliminates most anti-nutrient effects, and some anti-nutrients (like lectins) may even be good for us.

As for grains, Paleo proponents say grains can lead to inflammation and related health problems. This can be true for people with celiac disease (about 1 percent of the population) and for those with non-celiac gluten sensitivity.

But a substantial body of reliable research suggests that eating whole grains improves our health. At the very least, whole grains appear to be neutral when it comes to inflammation.

Bottom line on grains and legumes: Completely eliminating these important foods from our diet is probably a bad idea.

The problem with Paleo

Paleo-style eating has a lot of good qualities: It emphasizes whole foods, lean proteins, vegetables, fruits, and healthy fats. Incorporating more of these foods into your diet would likely be a big improvement.

However, the Paleo diet has some flaws. The evolutionary arguments don't hold up, and the evidence for excluding dairy, legumes, and grains isn't strong (yet).

But my biggest concern is this: A one-size-fits-all "best diet" approach doesn't work.

Strictly following a list of "good" and "bad" or "allowed" and "not allowed" foods is problematic for most people.

Even more, long-term, it's tough to be consistent on a strict diet regime like Paleo. Sure, most people can follow it for weeks or months. Maybe even years. But decades? That's unlikely.

Of course, without being consistent, you can't make progress.

What you can do today

Instead of signing up for a strict lifestyle template, think about small changes you can make in your "modern" life that support what your "ancient" body needs.

For example, look for simple ways incorporate a bit of what's good about the ancestral lifestyle into your day. Could you:

  • Eat a little more fresh food, like adding some fresh fruit or vegetables to dinner tonight?
  • Consider replacing a bit of the processed food you might normally be eating? (Not all of it, just some.)
  • Get outside for some movement and fresh air?
  • Go to bed a little earlier to get a good night's sleep?

These small actions -- done consistently -- can do much more for your health and happiness long-term. And consistency is more important than any food list or evolutionary theory.

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Want some help finding the best diet for you? Download this free guide: Paleo, vegan, intermittent fasting...Here's how to choose the best diet for you.

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About the author

John Berardi, Ph.D. is a founder of Precision Nutrition, the world's largest online nutrition coaching company. He also sits on the health and performance advisory boards of Nike, Titleist and Equinox.

Dr. Berardi was recently selected as one of the 20 smartest coaches in the world by livestrong.com, the internet's most popular fitness site.

In the last five years, Dr. Berardi and his team have personally helped over 30,000 people improve their eating, lose weight, and boost their health through their renowned Precision Nutrition Coaching program.

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