Updated: Mar 1
I‘m scared of trendy or catchy diets. I believe in reasonable and practical eating patterns, mostly those that have been proven by science to improve health and longevity. Where do we find the paleo diet on the spectrum of health, since it is one of the most googled diets ever.
The paleo diet gets a lot of things right. It tells you to ditch candy bars, doughnuts and processed junk. That's where we can agree. But here's where we don't. "Eat like a caveman" is the premise of this dietary pattern. I'm sure our paleo ancestors were the picture of health, considering the average life expectancy was less than 30 years. Cavemen didn't even survive long enough to suffer from chronic disease. So why are we promoting this diet and telling people it prevents them? In 2020, the paleo diet came in 3rd place among the most frequently googled diets. The keto diet came in first, and intermittent fasting came in second. I already summarized the science behind the keto diet and have an upcoming article on intermittent fasting. But for now, let's focus on paleo. In this article, instead of relying on recommendations from your latest guru, I'll deconstruct the paleo diet and detail what it is, if it's healthy compared to other diets and I'll break down the nutritional profile of this pattern of eating. In a nutshell, paleo diets have pros and cons.
What's A "Paleo" Diet Anyways?
Firstly, the term paleo refers to the paleolithic period, which ranges from 2.6 million to 12000 years ago. The paleo diet's premise is that for optimal health, we should eat like our cavemen ancestors did. They were more hunter gatherers than farmers, and so according to paleo proponents, our diets should rely on fruits, veggies, nuts, fish and meat. It also advocates for eliminating dairy, whole grains, beans and legumes, since these foods only appear with the advent of modern agricultural practices. Although it's logical to think that our body's nutritional requirements could have evolved according to foods we ate in the last 2 million years, why single out the last 2 million when we know that we've been evolving from our common great ape ancestors for the last 25 million years? Why focus on the last 10% of our evolution and ignore the first 90%? Data from various lines of evidence already support the view that humans evolved from a lineage of herbivores and so we were plant-based for more than 90% of our evolution. This might explain why we are so susceptible to heart disease, considering that in more than 90% of evolution, we didn't consume dietary cholesterol, since it's only in animal products. It doesn’t matter how much cholesterol you feed a carnivorous animal, say a lion or a dog for example, they DO NOT develop atherosclerosis, or blocked arteries. Yet, this very process is one of the greatest killers of humans in the westernized modern world.
Back to paleo. The pros: this diet also promotes avoidance of refined foods and ultra-processed junk, which is one thing we can agree on. Which is precisely why people eating a S.A.D. (standard American diet) tend to feel better and get healthier once they switch to a more paleo friendly diet. Processed and ultra-processed foods are definitely worse than animal products and so it's no surprise that metabolic parameters get better. What would happen if you gave a plant-based eater a paleo diet? Yup you guessed it, their metabolic parameters would get worse.
The Paleo Claims
People who move up the spectrum of health, from a highly processed diet to a more paleo-type pattern of eating will absolutely notice health improvements. Cutting out ultra-processed food, that accounts for 50-60% of our calories, tends to do that. Some of their other health claims have no scientific backing though, and that's where I come in. I don't like it when people use unproven claims to up-sell their products to unsuspecting consumers looking for a miracle. How can you claim chronic diseases will be prevented by a diet when it's based on a population that didn't even live long enough to get them? Getting eaten by a lion at 20 is a surefire way of not getting diabetes in your forties, but their claims range from curing cancer, to decreasing fatigue, to adding muscle and reversing diabetes. What part of these supposed health benefits is paleo and what part is the avoidance of processed crap. Which one of these claims are anecdotal and which are backed by peer reviewed science?
Sound the alarm!
Red flags everywhere. Firstly, any diet recommending avoidance of legumes, beans and whole grains should raise suspicion, since the evidence shows that these are precisely the foods that are associated with the lowest rates of chronic disease and the longest life expectancy in the world. We've been evolving for over 25 million years, so focusing on the last 10% of our evolution to determine our genetic make-up and how we should eat has no leg to stand on. Haters might try to convince you that through natural selection, our bodies evolved with animal products, so we have gotten efficient in metabolizing them, when studies show the opposite. One particular study showed that even when coupled with a high-intensity exercise program, putting people on paleo diets increased their bad cholesterol (LDL) by up to 20%. Since life expectancy was a mere 25-30 years in the paleolithic era, cavemen didn't live long enough to get cancer or heart disease. They simply lived long enough to reproduce and so natural selection would not have cared about living to 90, like we commonly see today.
Secondly, how can we assume that a paleo-type diet is protective in chronic disease when there is almost zero data that supports that claim. Remember? Science? That thing we use to prove or disprove hypotheses. How we can we assume that cavemen lived free from chronic disease when they didn't survive past 30. Exactly, we can't. If peer reviewed literature shows that a paleo pattern of eating is the optimal way of eating, I'll definitely update this article. Now, if you're eating Twinkies, the paleo diet will improve your health, since it does promote eating fruits and veggies. Paleo isn't the devil and it might even be something to strive for if you're currently eating a highly processed diet, but encouraging your dieters to avoid foods most associated with disease protection, like beans and whole grains, is not only irresponsible and dangerous, it's not based on any high quality evidence.
Moving In The Right Direction
I tend to repeat myself, so here it goes again. You can put different dietary patterns on a spectrum. On the far left we have a diet rich in processed and red meats, as well as ultra-processed foods. These people get more cancer, more chronic disease and live shorter and sicker lives. People on the far right eat a whole food plant-based diet containing at least 30-40 different plant varieties per week, while avoiding animal protein and processed foods. They live longer and healthier lives. Paleo is somewhere in the middle. You're avoiding refined foods and eating more whole foods, but you're also avoiding some of the healthiest foods in the world, such as legumes, beans and grains, while consuming saturated fats and cholesterol in meat. The goal in any health journey is simply to move towards the right, one plant at a time, by adding as much plant variety as possible. The more towards the right you feel like moving, the better for your health.
What Did Paleos Eat?
Yes, there are actual scientists that have donated their lives to studying paleolithic nutrition. Funny how authors of Paleo Diet books didn't think to check with the scientists first. According the science, and common sense, they didn't eat packaged food in a box or a bag. They didn't have McDonald's or deep fried chicken. They didn't consume salt, refined oils, fats or sugar. They didn't consume milk from another species and they didn't consume processed meats like ham, turkey slices, bacon or salami. True paleo diets, actually resembling the ones used in paleolithic times, are far different from the new paleo diets suggested on the bestseller shelf. Actual studies on paleolithic nutrition have suggested that our ancestors ate a predominantly plant-based diet, with some insects and small amounts of animal flesh. Studies have determined that our cavemen ancestors were eating upwards of 70 grams of fiber everyday, much more than the average of less than 15 g in Canada. When looking at all the other macro and micronutrients and comparing them in a "true" paleo diet, a "new" paleo diet and a calories matched plant-based diet, the nutrient discrepancies were shocking. The Paleo diet sold in bookstores looked nothing at all like what cavemen actually ate in paleolithic times. Talk about a well designed marketing scheme. What sells books is a diet that promotes a concept, an ideal, whether it relies on science or not. A book saying "eat like a caveman and lose weight, while enjoying bacon and red meat" is much more interesting than one that states: "broccoli helps prevent cancer". And we already know that cavemen didn't eat bacon, so why the hell would it be in your recipe book?
The Paleo Discrepancies
You now know that the Paleo diet in bestselling books is much different than the true paleo diet. They tried to match similar protein intakes, but didn't seem too worried about matching any of the other nutrients. There were many discrepancies between fiber, carbs, fats and many other nutrients when comparing "true" versus "new" paleo diets. Also, the meats we eat today aren't at all similar or as healthy as those eaten back then. Back then, wild meat would have been much richer in omega-3 and much lower in fat, accounting for 5-15% of calories instead of the 30-60% of calories from fat that we see in today's farmed animals. Their meats were also free of antibiotics, added hormones and environmental contaminants. Modern plants are also quite different, since they've been cultivated and bred for appearance, taste, transportability, digestibility and yield. Plants back then would have contained 3 times the amount of fiber per gram.
Short term trials have reported impressive results. Improvements in weight, satiety, lipids, blood pressure have been shown, but why? If you are in search of a miracle diet and your google search lands on paleo, you'll be avoiding refined grains, refined sugars, refined fat, refined oils, fast food, fried food, dairy products, processed meats and alcohol. Probably better than what you were doing before. In this way, if a plant-based diet seems impossible to maintain for you, maybe a paleo diet could be a move in the right direction. But remember this, the true Paleo diets that have been studied in these short term trials are much different than the ones being sold to you in book stores. Be careful. The diet that has these short term claims isn't the one they're selling to you. And although health improvements can be seen in the short term, I have significant concerns about adopting this diet long term. Paleo diets are extremely high in meat and we know that a high animal protein diet is very inflammatory and not health promoting. If you step back and look at the scientific data, the optimal amount of red meat you should be eating would be zero.
My Paleo Prescription
If you give someone who is eating a highly processed diet a paleo meal plan, they'll likely get better. They'll lose some weight, their blood pressure and other metabolic parameters might improve. Give someone eating a whole food plant-based diet a paleo diet, and their health markers will get worst. Use it as a stepping stone towards a more balanced dietary pattern if you must, but there are safer roads you could take. There are no miracle diets out there. Weight loss is achieved by calorie deficits, not catchy diets. Health is achieved by eating a diet high in antioxidants, vitamins, minerals, phytochemicals, fiber and healthy fats and by minimizing processed ingredients, saturated fat, heme iron and animal protein. The fun part about being an adult is that you can do whatever you want. If it's paleo your heart desires, then by all means, enjoy! But I believe that it's very easy for unsuspecting and naive dieters to buy in quickly to this trendy eating pattern, not knowing that they’re being sold something that is very far from an actual paleolithic pattern of eating .
Hopefully you learned something today! Please share this article and help your community increase their nutrition IQ. Check out my recent posts on the ketogenic diet, paleo diet and plant-based diet at plantbaseddrjules.com
Plant-based Dr. Jules 💚🌱
Pitt CE. Cutting through the Paleo hype: The evidence for the Palaeolithic diet. Aust Fam Physician. 2016 Jan-Feb;45(1):35-8. PMID: 27051985.
Challa HJ, Bandlamudi M, Uppaluri KR. Paleolithic Diet. 2021 Aug 1. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan–. PMID: 29494064.
Manheimer EW, van Zuuren EJ, Fedorowicz Z, Pijl H. Paleolithic nutrition for metabolic syndrome: systematic review and meta-analysis. Am J Clin Nutr. 2015 Oct;102(4):922-32. doi: 10.3945/ajcn.115.113613. Epub 2015 Aug 12. PMID: 26269362; PMCID: PMC4588744.
Jamka M, Kulczyński B, Juruć A, Gramza-Michałowska A, Stokes CS, Walkowiak J. The Effect of the Paleolithic Diet vs. Healthy Diets on Glucose and Insulin Homeostasis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. J Clin Med. 2020 Jan 21;9(2):296. doi: 10.3390/jcm9020296. PMID: 31973038; PMCID: PMC7073984.
de Menezes EVA, Sampaio HAC, Carioca AAF, Parente NA, Brito FO, Moreira TMM, de Souza ACC, Arruda SPM. Influence of Paleolithic diet on anthropometric markers in chronic diseases: systematic review and meta-analysis. Nutr J. 2019 Jul 23;18(1):41. doi: 10.1186/s12937-019-0457-z. PMID: 31337389; PMCID: PMC6647066.
Ghaedi E, Mohammadi M, Mohammadi H, Ramezani-Jolfaie N, Malekzadeh J, Hosseinzadeh M, Salehi-Abargouei A. Effects of a Paleolithic Diet on Cardiovascular Disease Risk Factors: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Adv Nutr. 2019 Jul 1;10(4):634-646. doi: 10.1093/advances/nmz007. Erratum in: Adv Nutr. 2020 Jul 1;11(4):1054. PMID: 31041449; PMCID: PMC6628854.