Get full access to Outside Learn, our online education hub featuring in-depth nutrition, fitness and adventure courses, and more than 2,000 instructional videos when you sign up for Outside+..
Is the Paleo diet a healthy way to go or just another fad?
— Jack T., Dallas
The theory behind the Paleo Diet becomes clear if you think, for a minute, about the giraffe.
Giraffes, with their majestically long necks, evolved to thrive in a particular environment. In their natural habitat, the tastiest food you can imagine—assuming you are a giraffe—are the nourishing leaves that grow on the upper branches of acacia trees. These trees easily grow to 30 feet. Giraffes with shorter necks starve and pass on fewer “short neck” genes. Long-necked giraffes, on the other hand, thrive in this environment, reproducing, and peppering the gene pool with more “long neck” genes. When this keeps happening over eons, you have the giraffe as we know and love him. A perfect—if oversimplified—example of how genetics adapts to an environment in a way that ensures the continuation of the species.
The theory behind Paleo is that we humans are also “genetically adapted” to a particular kind of food environment—a food environment that existed for most of the 2.6 million years the human genus has been around. Food you could hunt, fish, gather or pluck. Nutritionist Patrick Quillan once labeled this diet the “factory specified fuel” for humans. It’s been the diet of homo sapiens for at least 100,000 years.
In contrast, the first supermarket opened in 1930—less than 100 years ago—and the first McDonald’s franchise opened in 1953. And according to the Paleo crowd, there’s a great disconnect between the diet our genes are crying out for and the diet we actually eat.
So what should we be feeding our genes? Well, if you follow the Paleo diet, there are three things you won’t be eating: dairy, beans, and grains. Additionally, sugar and virtually all processed foods are forbidden. What you will be eating is lots of meat, poultry and fish, as well as berries, nuts, fruits, and vegetables.
Paleo proponents point out that crops like wheat, corn, and potatoes are all products of modern agriculture (“modern” meaning in the last 10,000 years, a mere blip on the time clock of human development). Paleo folks feel—not without some justification—that our genetics simply have not had time to catch up with these newfangled foods.
Not only are we eating foods that we have not evolved to eat, we’re getting the majority of our calories from them. They’re not just occasional treats—they are our predominant source of calories.
Does Research Support Paleo?
There isn’t a great deal of research on Paleo eating, so we have to rely on the clinical experience of the many nutritionists and health professionals who swear by this way of eating and recommend it to their clients. Admittedly, the collective experience of thousands of people won’t satisfy those who need randomized, controlled, double-blind studies before they endorse anything, but that doesn’t mean we should ignore valuable clinical experience. After all, as the late great nutritionist Robert Crayhon used to say, “The NYC fire department doesn’t have a double-blind study showing that water puts out fire, but that doesn’t mean it doesn’t work!”
People report far more energy on Paleo than they had on their former (usually bad) diets. Weight loss is also common. Some Paleo gurus—like Robb Wolf, for example, author of The Paleo Solution—originally turned to Paleo to conquer serious gut problems. Many of these folks report improved digestion and elimination, and a noticeable boost in well-being.
Although Paleo and “low-carb” do not mean the same thing, the eating plans do overlap. But you can eat far more carbohydrates on Paleo than you’d ever get away with on the Atkins diet, where carbs can be limited to as little as 20 grams a day. Low carb expert and researcher Professor Jeff Volek, PhD, RD, estimates that the average Paleo dieter consumes about 30 percent of calories from carbohydrates. All vegetables and all low-sugar fruits like berries and apples are virtually unlimited on Paleo, which alone distinguishes it from most classic low-carb plans.
To Bean or Not to Bean?
One area of controversy about Paleo is the ban on beans. The reason given for the “off limits” sign on beans and legumes is that these foods contain compounds called lectins that can cause inflammation. But beans and legumes are great sources of fiber and antioxidants. And some experts think lectins may not be as harmful as believed. “From my experience treating thousands of patients over the years, only about 10 percent of them react to lectins,” says Steven Masley, MD, director of the Optimal Health Center in Florida and author of The 30-Day Heart Tune-Up.
Luckily, Paleo is fairly forgiving. Even Wolf told me that he doesn’t stick to the program 100 percent of the time, and orthodox Paleo proponents like Loren Cordain allow for about three “off-duty” meals a week where you can wander away from the basics. Some Paleo gurus have even confessed to me—off the record—that they’ll frequently experiment with beans for some of their clients. I haven’t found any, however, who endorse grains, dairy, or sugar.
Are There Any Caveats?
There are a couple of things you should be aware of before you embark on this plan.
Chris Kresser, LaC, author of Your Personal Paleo Code, points out that in a few cases, making a quick switch to Paleo may bring about some digestive problems and sugar cravings. Kresser thinks—and I agree—that in the majority of cases, people who find themselves with digestive issues on Paleo probably had them before they started this way of eating. The symptoms may suddenly become more noticeable on a healthier diet because they were being hidden by poor eating habits.
I’ll explain. Consider what happens when you stop smoking—many people feel a lot of anxiety. But that anxiety was present before—you just didn’t notice it as much because you were smoking. Smoking was compensating for that anxiety, an attempt to “self-medicate.” When it comes to stomach issues, the same is sometimes true. For example, someone with low stomach acid may be unconsciously compensating by eating fewer foods that require stomach acid in order to digest them properly. Or a diet high in simple, empty carbs may be hiding low enzyme activity. Or a low-fiber diet may be hiding chronic inflammation in the gut. (“Consuming large amounts of insoluble fiber when your gut is inflamed is like rubbing a wire brush against an open wound,” says Kresser.)
So in a way, unhealthy food choices may do the same thing that cigarette smoking does for anxiety—prevent you from noticing things like inflammation or digestive problems that were there all the time. That doesn’t mean those unhealthy choices were good ones. It just means they were successful in suppressing the overt symptoms of your underlying problems.
Kresser points out that gut problems like low stomach acid, decreased enzymes, and gut inflammation have several causes, such as parasites, bacteria, or fungi. Going Paleo won’t necessarily eliminate these problems, and they should be worked on with a good health practitioner.
The Bottom Line
David Katz, MD, director of Yale’s Prevention Research Center, recently reviewed popular diets to find out if they had anything in common. They did. “The best (diets) push real foods that are minimally processed or direct from nature,” he says.
And at the end of the day, that’s exactly what Paleo is about. Real food. Food your grandmother’s grandmother—and her grandmother before her—would have recognized. That, after all, is the basis of every healthy diet ever invented. It’s a hard prescription to argue with.