Alan Aragon is a nutrition expert and renowned Paleo critic that writes research reviews on the latest nutrition publications, writes a monthly column in Men’s Health Magazine, and is also a continuing education provider for several organizations, including the Commission on Dietetic Registration, National Academy of Sports Medicine, and the National Strength & Conditioning Association.
Aragon has been openly criticizing the Paleo Diet for over a decade, so I asked him a few questions about his background and opinion of the Paleo Diet and Paleo Movement in general to gain some insight and clarity to his oppositional stance.
I’ve spent the majority of my career in nutritional counseling, but as of the past few years, I’ve been progressively more involved in research and conference lectures. My areas of concentration are the integration of training and nutrition for altering body composition or enhancing exercise performance (my latest publication is here). I have two primary research projects in the works and one secondary research project that should make it past peer review hopefully before the year is over. I’m also working on a book for the lay audience, and at this point I’m not too sure how much I can divulge about that. The speaking road will lead me to London and Canada before the year is up, in addition to my regular speaking spots at the Fitness Summit and the NSCA. My formal bio can be seen here.
Are you trying to tell me I’m over the hill? If that’s the case…then I can’t argue with you on that. In all seriousness though, AARR (Alan Aragon’s Research Review) is a monthly review of the scientific literature related to nutrition, training, and supplementation. It’s what I do to stay on top of the current research, and help other health/fitness professionals and enthusiasts do the same. It’s an outlet for me to pour out my nerdy obsessions, when you really boil it down. Both the theoretical and practical sides are covered. I also have various guest contributors from all corners of the allied health fields, so it’s pretty diverse in terms its scope of content.
It’s logically faulty to just assume that pre-agricultural times were optimal in terms of nutritional circumstances, and general health circumstances, for that matter. Some of the most significant technological breakthroughs for improving human health and preventing/treating disease occurred within roughly the last century. The march of technology can be both good and bad, but let’s not dismiss or ignore the enormous amount of good. But beyond that, many whole foods (both plant & animal) of the present day did not exist in the Paleolithic period; they are products of modern-day farming and food engineering, so that virtually kills the objective right there. The best practical move we can make as modern-day humans is to predominate our diet with whole and minimally refined foods, while judiciously moderating the “naughty” stuff. One thing that really bugged me was seeing potatoes (a whole, nutrient-dense food) on the list of banned foods set forth by pioneering Paleo diet researcher Loren Cordain. Talk about going full-potato!
I don’t think it’s practical or even accurate to assume population-wide extreme intolerance to grains and legumes. The issue with grains inevitably boils down to some level of gluten intolerance. The most current estimates of celiac disease prevalence fall below 1% of the population. As far as non-celiac gluten sensitivity (NCGS) goes, a very recent study led by Daniel DiGiacomo of the Celiac Disease Center at Columbia University estimated that the national prevalence of NCGS is a smidge over 0.5%, which is about half the prevalence of celiac disease. I’ve seen higher gluten sensitivity prevalence estimates in less reliable literature, but the bottom line is that the gluten-tolerant fraction of the population is likely to be well over 90% of us. So, it simply makes no sense to view gluten-containing foods as universally “bad.” Adding to the illogic of banning foods that are tolerable by the vast majority of the population, the traditional Paleo diet doctrine selectively ignores the fact that ‘Paleo-approved’ foods (i.e., nuts, fish, and shellfish), have a combined prevalence of allergenicity comparable to – and by some estimates even greater than that of gluten-containing grains. Another amusing fact is that 4 of the 8 “major food allergens” designated by the Food Allergen Labeling and Consumer Protection Act are Paleo-approved.
If you include taste enjoyment as an indirect benefit to health, then I’d say yes, that applies to all of those foods. Anyone who can tolerate a given food, and truly enjoys the food, should not force the avoidance of it. This rigid, all-or-nothing approach to dieting is a recipe for disordered eating in susceptible individuals. Speaking of the foods from a nutritional standpoint, I’d also say yes. Every species of food has its own unique nutrient profile – and I’m not just talking about essential vitamins and minerals. There are a plethora of phytonutrients (& zoonutrients) in those foods that may act individually or synergistically to promote health and/or inhibit disease. Let’s take oats, for example. There is a substantive body of research pointing to multiple beneficial effects attributed to the beta-glucan content, and other non-essential components of oats. These benefits range from appetite control (as indicated by increases in peptide Y-Y) to enhanced immune response, and improvements in blood lipid profile and glucose control. The list goes on. As for dairy, I pity the poor soul who can digestively tolerate dairy just fine, truly enjoys it, yet avoids it just because it breaks Paleo rules. I’ll quote research by Rafferty & Heaney on the nutritional profile of milk:
“NHANES 1999–2000 and CSFII 1994–1996 analyses of food sources of calcium, vitamin D, protein, phosphorus, and potassium reveal milk to be the number 1 single food contributor of each of these bone-related nutrients with the exception of protein in all age groups of both sexes…”
Regarding legumes, the aforementioned principles apply. Furthermore, I’ve repeatedly challenged folks to show me research indicating the adverse effects of whole legume consumption (not soy protein isolate by the bucketload) in healthy humans. Invariably, I hear crickets. In contrast, the scientific literature (in both observational and controlled studies) on the health benefits of legume consumption is substantial. Peanuts are legumes, and peanut butter (especially combined with chocolate) has been known to impart magical powers. Your mileage may vary on this. An interesting bit of information that folks ignore or overlook is that legumes are common staples of some of the healthiest populations in the world. In fact, Dan Buettner (of Blue Zone research fame) reported that beans, including fava, black, soy, and lentils, are the cornerstone of most centenarian diets. Of course, this is observational data with many potential confounding variables. Nonetheless, it warrants caution against the assumption that legumes are the bad guys. I’ve recently made the point that traditional Mediterranean populations have intakes that violate every food restriction rule of the Paleo diet, but they’re busy being too healthy to give a damn.
For those who enjoy grains, yes. I am a big believer in respecting your own personal taste preference, and letting that override the rules and formalities of any given fad diet. If grains don’t suit your personal taste, then by all means don’t eat them. It’s the idea of banning them universally despite a lack of supporting evidence that I take issue with. For those who DO have the desire to eat grains but have issues with gluten intolerance, the good news is that commercially available gluten-free grains outnumber gluten-containing grains by at least 2 to 1 (complete resource here).
Well, right off the bat, I wouldn’t do a knee-jerk recommendation to avoid all grains, legumes, and dairy. The British Dietetic Association recently published evidence-based guidelines for the management of irritable bowel syndrome (IBS). In summary, lowering the intake of fermentable carbohydrates is recommended. Also, avoiding or minimizing gluten-containing foods may be necessary, but let me reiterate that there’s still a fair range of gluten-free grain foods available to choose from if the person likes grains. Lactose-containing foods can be problematic, so their minimization or elimination should be considered as well (note that low & no-lactose dairy products are abundant). A high consumption of fructose has also been implicated in exacerbating IBS, so this should be moderated as well. Indiscriminately having an IBS patient “go Paleo” can potentially lead to problems since there are Paleo-approved foods are high in fructose, fructans, and polyols suspected to aggravate IBS. However, I would concede that as a quick-and-dirty shotgun solution to managing IBS, the Paleo diet model is actually quite a good approach. I would also encourage screening and treatment by a gastroenterologist (or similar qualified medical specialist), since many times the treatments for digestive disorders are beyond the scope of nutritional modulation alone.
Yes, it is unfounded. There’s no objective evidence demonstrating the optimality of a 1:1 ratio of dietary omega-6 to omega-3 fatty acids. It’s all speculation without a solid research basis. For example, the ratio of omega-6 to omega 3 in coconut oil (a Paleo fetishist favorite) is almost 4000 to 1, yet the weight of the evidence does not indict coconut oil as an agent of adverse effects. Most commercially available land animals’ fatty acid composition has omega-6 content that’s many times greater than its omega-3 content. So, if we were to strive for a 1:1 ratio in the diet, we’d have to minimize the consumption of beef, chicken, pork, etc. It’s just silly. In line with this, the higher proportion of omega-6 fats in whole foods of plant origin such as nuts is not a concern. The evidence of omega-3 consumption’s beneficial effect on health indexes is abundant, so I would recommend keeping fatty marine foods in rotation in the weekly menu in order to reap these benefits. For those really worried about it, omega-3 supplementation is always an option.
It depends. I’d say in rational, health-conscious, physically active adults, the fear of sugar is indeed unfounded. In children and adolescents (who are mostly clueless about health, lets’ face it), sugar consumption is often unbridled & combined with physical inactivity, so yeah – the concern is there. The crux of sugarphobia centers around fructose, which is an almost unavoidable component of commercially available sugar-sweetened products. Table sugar itself (sucrose) is half glucose, half fructose, and high-fructose corn syrup (HFCS) which is ubiquitous in soft drinks and packaged sweets has a slightly but inconsequentially higher proportion of fructose. Many are familiar with Robert Lustig’s campaign against sugar, and his emphasis on the evils of fructose. What often fails to be addressed is that dose and context make all the difference in the world. The research indicting fructose as an inherent agent of harm uses artificially high doses that are many times greater than typical human intakes. Much of this research is rodent-based, and rodents’ capacity to convert dietary carbohydrate to fat is roughly ten-fold that of humans. There are several diligent scientific reviews that have been done on this topic, which I would encourage everyone to read, since the full text is publicly available. To quote a recent review by Salwa Rizkalla:
“Despite the epidemiological parallel between the marked increase of obesity and fructose consumption, there is no direct evidence linking obesity to the consumption of physiological amounts of fructose in humans (≤ 100g/day). A moderate dose (≤ 50g/day) of added fructose has no deleterious effect on fasting and postprandial triglycerides, glucose control and insulin resistance.”
I would also encourage everyone to read John White’s recent review challenging the fructose hypothesis, whose key points are quoteworthy:
“In considering the volume of contemporary literature on fructose, 1 conclusion stands clear: fructose is safe at typical intake levels but can produce adverse metabolic effects when abused—as is true of most nutrients. It turns out that the largest abusers of fructose are not American consumers, but research scientists. […] It is only when researchers hyperdose human and animal subjects with fructose in amounts that exceed the 95th percentile by 1.5- to 3- and 4- to 5-fold, respectively, that adverse effects are provoked.”
The way I see it, the practical take-away for the general population would be to keep added sugar (as opposed to intrinsic sugar in milk or whole fruit) limited to roughly 10% of total calories. This will allow for moderation & sane dietary practices while also hedging your bets away from the adverse potential of excess intake. Certain athletes involved in high-volume endurance competition (and other highly physically active folks) can safely exceed this in order to meet the demands of their sport.
My biggest gripes with the Paleo Movement is the extreme-ism and absolute-ism that some folks apply to food avoidance despite a lack of supporting research evidence. And even the “Primal” model of going 80% Paleo while leaving 20% for the non-Paleo stuff is rather humorous. For example, in the context of a typical 2500 kcal diet, 20% of those calories coming from grains & dairy would constitute 500 kcal – which is the capacity for a typical bowl of cereal. So, if a bowl of cereal (or 2 cups of pasta, or 4 slices of bread) every day qualifies as Primal, then it sounds a lot like conventional eating to me. It’s just difficult to tolerate the lack of logic there. I generally can’t stand the labeling or branding aspect of a diet, or the universalization of diet rules. This is because individuals have vastly different preferences, tolerances, and goals for the function of their eating habits.
As for what I appreciate about the Paleo movement, the push toward consuming more whole foods is definitely a positive thing. I appreciate guys like Robb Wolf & Mat Lalonde who are much more flexible and objective in their approach & philosophies than the majority I’ve communicated with in the Paleo sphere. Last but not least, I like the CrossFit training attire.
Not that I can think of at the moment, this should be plenty to get people thinking. I want to give thanks and credit for being the first Paleo-focused publication to reach outside the box and interview me.
To learn more about Alan Aragon, visit his website here.
Karen Pendergrass is an ENTP who is an enthusiast in a myriad of areas including Agricultural Sustainability, Food Politics, Applications of Bacteriotherapy, Autoimmunity, Color Theory, Hard Determinism, Social Technologies, and Social Engineering. She is the Founder of the Paleo Foundation, the International Paleo Movement Group (IPMG), author of the not-yet-published Sustainability Diet, and Founder of DinnerCrasher.com.