The 20th century was an exciting time for fad diets, including the byzantine, the bizarre, and the utterly nonsensical. One such diet started cropping up in the 1960s, alongside the back to the land movement: An early form of what we call the “paleo” or “primal diet” today, consisting of unprocessed natural foods, with a heavy dependence on meats, certain vegetables, nuts, fruits, and seeds.
And little else. Like Atkins, another diet that proved extremely popular in the second half of the century, the paleo diet eschews carbohydrates, but it’s even more extreme, requiring adherents to cut out all processed foods, eschewing all grains, and eliminating legumes along with dairy products. It’s notoriously expensive and quite difficult to adhere to, and it’s become one of the most hotly debated diets of recent years as adherents with ardent personal testimonials do battle with vitriolic critics. This year, it came in dead last on U.S. News & World Report’s “Best Diets” ranking, which relies on research and the opinion of experts like doctors and dieticians.
For those who haven’t been inducted into the world of paleo yet, it’s not just a diet: It’s a way of life, and people who eat it treat this way like an identity, not simply a series of dietary decisions. Fans of the diet tend to push hard in the hopes of winning converts, and there’s a great deal of crossover with the CrossFit community (speaking of fads that have been controversial, but more about that in a moment). If you don’t eat paleo, they’ll tell you, you should be, and if you criticize paleo, prepare for substantial pushback as they outline all the reasons a primal diet is superior.
A massive online community of paleo people thrives on blogs, websites, and bulletin boards, including sites like Paleo Mom and The Primal Parent (who wrote a passionate defense of eating raw and rotten meat). Testimonials about the diet include claims that it makes people feel more energetic, leaves them feeling glowing with vibrant health, and reduces the risk of so-called “diseases of civilization” like heart disease and diabetes. Paleo cures autism, puts auto-immune diseases in check, and more, according to fans and converts.
The fundamental argument behind the paleo diet is that humans were healthier 10,000 years ago, and that one reason is the diet they consumed (unlike us, they also didn’t deal with hipsters, Glassholes, and a non-stop, always-on society, which may also have something to do with it). Existing primarily as hunter-gatherers meant that people ate a great deal of fish, meat, nuts, seeds, fruit, some vegetables, and little else. Authorities in the paleo world claim that eating a minimally processed diet can reduce health problems, and on that score, they’re definitely right, as numerous studies have demonstrated.
But is their diet the right diet, and do their arguments hold up?
Let’s take a look at the health of our hypothetical cave man (or lady). Most people living over 10,000 years ago didn’t live past 40, and a huge majority died below the age of 18. This was due to a wide variety of factors, including predation, childhood disease, and poor sanitation, but hunger and limited food availability likely played a role, just as they do in the health of extant hunter-gatherer communities today.
Furthermore, about those diseases of civilization. A Lancet study taking a look at mummies from communities all over the world found signs of atherosclerosis in 47 out of 137 bodies, indicating that whatever those people were eating, it wasn’t preventing buildups of fat in their bodies. One thing they definitely were eating, though, was carbohydrates and sweets like honey, as evidenced by the appearance of dental caries in skulls ranging from 15,000 to 13,900 years old. This suggests that diet-related health problems were in fact a part of life for earlier generations.
What else were they eating? Certainly not much found in the pantries of most paleo dieters. Every aspect of the modern human diet, not just processed foods, has been shaped by centuries of human interference. Long before anti-GMO campaigns, humans were genetically modifying organisms large and small all around them. Almost every food animal and crop currently on the market was bred to be larger, more flavorful, more nutritious, and more appealing to human consumers. Vegetables as we know them were almost nonexistent, including crucifers (also known as brassicas, also known as the huge group of cultivars of just one species of vegetable, Brassica oleracea, that’s been spun off into broccoli, Brussels sprouts, cabbage, and kale, among others).
Meats, too, have changed dramatically. It’s not just that animals are bred to be larger, but that their diets are also radically different, changing the nutritional and structural composition of their flesh. While paleo adherents warn that it’s important to buy organic, grass-fed animals raised in humane environments, there’s considerable leeway under the organic label, and they might be surprised by the conditions some of their favorite meats are raised under.
Fans of paleo also frequently claim that humans haven’t evolved significantly in 10,000 years and thus haven’t adapted to the stresses of eating packaged foods and a diet high in carbs. In fact, evolution and science are a lot more complicated than that. While it’s true that humans haven’t undergone a huge evolutionary shift in the last 10,000 years akin to the moment hominids started exploring this whole walking upright thing, they have evolved.
In fact, as genetic studies of the global population show, they’ve evolved enough for your genes to betray key information about where you’re from and who your ancestors were. Humans have evolved to digest dairy, to resist certain diseases, and to cope with other environmentally-specific threats. In Europe, the gene that allows people to guzzle down milk is alive and active, thanks to the fact that cattle were domesticated and farmed widely throughout the region. In Japan, however, that genetic shift lags, as dairying wasn’t a significant part of Japanese culture until recently.
If anything, even 10,000 years ago, humans had evolved to become resourceful, flexible eaters who were willing to eat whatever came their way, because they had to be, and that same trait has been passed on today. Unlike more geographically limited species, we don’t have the luxury (and tragedy) of becoming dependent on a narrow range of foods—we are not, for example, like the doomed panda, stuck on a bamboo broken record. We are obligate omnivores, able to eat and safely digest a huge range of foods, including the verboten grains and legumes. There is no specific “caveman diet” that was eaten globally 10,000 years ago, just as hunter-gatherer societies today don’t eat the same diet worldwide.
Instead, people ate what they could find in their regions, when it was seasonally available, and they moved when food supplies ran out. It was a harsh life in which a huge amount of energy was dedicated to food, until the day some bright person decided to try the idea of planting a few things. That day likely happened earlier than we realize: Human history is not fixed and static, and it’s unlikely every society adopted agriculture at the same time, or that the oldest agriculture in history dates to 10,000 years ago, given how difficult it can be to find evidence of early agricultural pursuits. Failed crop experiments, for example, wouldn’t show up in coprolites. Certainly people were storing and consuming grain well before 10,000 years ago, and cheese was a part of the diet as early as 7,500 years ago.
Paleo adherents today do little to no hunting and gathering, unless the aisles of Whole Foods have turned into the savannah. Some may engage in urban foraging, but few live near regions where it’s feasible to actively hunt for food and forage for nuts and berries. More to the point, they likely wouldn’t want to, as most of their time would be taken up with searching for food instead of working, participating in the paleo community, and enjoying free time. One of the reasons humans adopted agriculture so widely and so readily is because it revolutionized society, creating a world where people had time to create art and culture. And not spend all their time chasing after antelope.
Fans of the paleo diet argue that this is where humanity went wrong, that along with art, culture, and living in fixed villages came radical changes to our bodies, lives, and health. In many senses, they’re right: Living in fixed communities improved our diet significantly, provided more time to breed and refine crops for better nutritional yield and performance, and offered a chance to domesticate and keep animals. It did come at a cost, though—settlements became breeding grounds for disease, a consequence of keeping people crowded together in close environments. Cities became hazard zones, a paradise for microbes. Tradeoffs are the way of life.
Within the cities of today, made cleaner and healthier than ever before, paleo fans believe that returning to an old way of life will act as a silver bullet, curing social ills. Disturbingly, some of them may actually be making themselves sick. While it’s easier to meet your nutritional needs when you can forage in the produce section and hunt at the local butcher’s, malnutrition can still be an issue on a limited diet, as humans aren’t adapted to eat restrictive diets. It’s not just about meeting caloric needs, but accommodating other dietary needs as well.
Milk, for example, is an excellent source of calcium and Vitamin D, both of which are critically necessary for life. Especially for women, meeting daily calcium needs is very important, as they can be subject to osteoporosis later in life. Calcium deficiency was one of the issues cited by U.S. News & World Report in their evaluation of the diet. They also noted that few studies, with extremely small sample sizes, have been conducted on paleo eating, making it difficult to determine the long-term risks and benefits. In a balanced paleo diet with a rich supply of fruits, allowed vegetables, nuts, and seeds and a limited amount of meat, dieters will get fiber and lots of nutrients, but if they rely too heavily on meat, they can also get themselves into trouble, as meat isn’t a complete food for humans.
Noted dietary commentator Marion Nestle doesn’t understand why legumes, dairy, starchy tubers, and grains are nixed from the paleo diet, when ample science suggests they can play a vital role in a balanced diet. “I can’t think of any nutritional reason why such foods should be prohibited,” Nestle says. Along with other experts in the nutritional field, she also raises concerns about the amount of meat in the paleo diet, specifically, the amount of fatty meats. While the war over fat is far from over, numerous studies have linked a diet high in animal fats with adverse health events in the long term—and one popular paleo travel food and snack is pemmacin, appropriated from Native American communities and comprised of dense fat and protein. When you were out hunting and gathering all day, pemmacin made sense as an easily-packed and consumed trail food. If you’re spending most of your time in your office, it’s more dubious.
Overall, authorities on healthy eating generally agree that the best diet contains a balanced mixed of minimally processed foods including lean meats, vegetables, fruits, whole grains, legumes, and tubers (yams are a great source of energy and they’re packed with nutrients). On this score, paleo eaters are right: Unprocessed foods offer dietary and health advantages. Some nutritionists suggest a happy medium: An 80/20 split between paleo and a more mixed diet.
Another issue that often isn’t addressed is the expense and burden of eating a paleo diet. It is, in essence, a diet of privilege. Sustainably-sourced fish and meats are expensive (even their conventional parts are). Organic, high-quality produce is expensive. So are nuts and fruits. Paleo dieters must live at a higher economic standard to sustain their diet and stay healthy, at least, if they want to adhere to the rules. In a country where 14.5 percent of households experienced “some” food insecurity and 5.7 percent experience “very low” food security annually, the cost of food is a very real and serious issue. The diet also requires a great deal of food preparation (particularly for those who struggle with adhering to it, and who try to make it as varied as possible to retain interest).
In today’s society, the sad reality is that many people lack time for food preparation due to constraints like child care, work, and other obligations. Notably, many of the active paleo blogs are run by women, especially mothers, another reminder that even in the paleo world, women are expected to perform the bulk of the labor when it comes to sourcing and preparing food for the family. Is paleo a good solution for families struggling with food insecurity and limited time availability?
Ultimately, people’s eating decisions are their own, and it’s critical to avoid assigning value judgments—one way or the other. The paleo diet isn’t really historically or scientifically accurate, but that doesn’t make it invalid for people who experience benefits from it, though they shouldn’t be dangerously touting it as a cure-all for an assortment of serious illnesses or using bad science to advance their cause. And while it’s tempting to attack the cult of paleo, let those without sin cast the first stone: Are you so sure there’s nothing in your life that hasn’t taken on an element of the cultish, stubborn following? Ardent Mac fan? Fiendishly dedicated to YA? Think veganism is superior? All of us have causes we passionately believe in and pushing those causes (or denigrating others) isn’t the way to win friends and influence people.