Review of “Diet Cults” by Matt Fitzgerald

In his book, Diet Cults, Matt Fitzgerald lumps all diets into one category — cults. These “cults” he says, are fundamentally flawed, and the evidence of their flaw is that they all assert their superiority over one another. Since they can’t all be correct, they must all be wrong. From there, his book takes us on a bizarre journey jumping from one of Matt’s pet “diet cult” peeves to another, all while cherry picking research that conforms to his own beliefs about what constitutes a healthy diet.
One of the things that makes “diet cults” eminently frustrating to read is how often Fitzgerald contradicts himself in his writing. The theme of his book is that there is no singular way to eat for health, yet he continually recommends mainstream guidelines such as the SAD (Standard American Diet) as a way to eat for optimal health.

Considering the fact 2/3 of Americans are either overweight or obese, I fail to see how mainstream recommendations such as the SAD should be used as a template for an optimal eating strategy. The reason diet fads are so popular in the first place is because the SAD has failed us so miserably.

Another thing that makes “diet cults” so frustrating to read is the paucity of research went into the writing. If you’re going to attack something, at least do the research and find out what you are against. By Matt’s own admission, he doesn’t actually read the books he attacks. In a Nov 2013 interview with Endurance Planet, Matt says:

“I actually don’t read many of these books, because they just make me tear my hair out, but my understanding is that in Loren Cordain’s book, he says that, like, you know, that this is the diet we were all meant to eat, in no uncertain terms, because I actually quote it in the book.”

Since he didn’t actually read any of the books he’s against, it makes sense why I found so many errors, such as his claim that the Paleo Diet advocates eating a 50% meat diet. But, in Cordain’s book, The Paleo Answer, he specifically says not to eat more than 35% of calories from protein, as it becomes toxic to the body above that threshold.

Fitzgerald also claims that The Paleo Diet author Loren Cordain advocates “eating just like a primordial hunter-gatherer”. Yet, in my interview with Cordain, he advocated a diet that allows us to find foods at our local grocery store that are similar to the nutritional quality of our ancestor’s foods. He never says that we should eat exactly like our primordial hunter-gatherer ancestors.

I found so many errors of this sort when he was attacking The Paleo Diet, it made me wonder what research he did, aside from conducting a few Google searches or reading some tweets in his spare time. It also made me wonder about the veracity of the claims he made about other diets that I am less familiar with.

Mainstream Nutrition

Matt also gets it wrong when it comes to mainstream nutrition. He quotes Marion Nestle as a mainstream nutritionist saying,

“The range of healthful nutrient intake is broad and food from the earth, tree, or animal can be combined in a seemingly infinite number of ways to create diets that meet health goals”.

But we shouldn’t take this quote by Nestle as an endorsement of the mainstream Food Guide Pyramid. Her reaction to the Food Pyramid was more skeptical. When asked about the Food Pyramid in 1991 she said,

“The USDA is in the position of being responsible to the agriculture business. That is their job. Nutrition isn’t their job.”

A Rational “Agnostic” Diet?

Fitzgerald chastises those who follow one of the “diet cults” for thinking that they have come to their way of eating through rational, scientific analysis. A more honest analysis, he says, shows that we all come to our own way of eating based on our personalities and food preferences.

Matt, ever the rational philosopher, prides himself on taking an “agnostic” approach to healthy eating; presumably believing that he has somehow escaped the emotional tendencies that guide the rest of us. What he fails to see is how his own dietary choices are just as biased and influenced by circumstance as everyone else’s.

Complexity in Nutrition

The problem with studying human nutrition is that it is an infinitely complex science and it’s difficult to form conclusions based on scientific studies alone. There are so many uncontrolled variables present during any study that it makes it nearly impossible to draw hard conclusions.

Rather than seeing nutrition science for what it is: a budding science that has yet to make its way to the hard sciences, Matt thinks that mainstream nutrition has basically nailed down what we should eat.

The fact that there are so many conflicting studies, points to the idea that nutrition is still a new science that shouldn’t be taken too seriously. Nutrition is more like the alchemy that preceded modern chemistry. It’s still greatly lacking and is prone to the bias, whim, and prejudice.

Evolutionary Principles

If mainstream nutrition has figured it all out, as Matt suggests, why is it that despite our best efforts to maintain a healthy diet, so many of us are tired, depressed, and overweight? Anthropologist Daniel Lieberman shows in his book, The Story of the Human Body, that a long list diseases like obesity, acne, flat feet, myopia, depression, anxiety, heart disease, fatty liver disease, and type II diabetes, are rare amongst hunter-gatherers, and often have roots in our modern diet and lifestyle.

Taking a true agnostic approach to eating would be more like that of Weston A. Price, a dentist in the early 20th century. Price was one of the first to point out what was so wrong with our modern diets. He showed that modern man’s teeth, despite special care, suffered from cavities and decay, while indigenous people around the world never brushed their teeth and kept most of their teeth into old age. Price found that the dietary practices among indigenous people varied widely, but lacked the processed packaged foods, refined grains, and sugar, common in modern diets.

Traditional diets also placed great emphasis on food preparation. Indigenous peoples knew that certain food such as grains, legumes, and dairy were difficult to digest. When consuming those foods, they employed elaborate preparation methods such as soaking, sprouting, and fermenting. This made the food more nutritious and easier to digest. Michael Pollan points this out in his latest book Cooked. He shows how modern food preparation, in the name of convenience forgoes traditional methods, and the nutrition of our food suffers.

A Broader Perspective

Fitzgerald places a lot of emphasis on “real world” results, but dismisses the positive experiences of those who follow ancestral or Paleo style diets. He sees them as being co-opted by cult-like thinking. Ignoring the diets of our ancestors misses a huge sample size of past generations that we must include if we want to find out what kept our ancestors healthy and robust. One need not go back to the days of the paleolithic to understand what makes a healthy diet, but taking a broader perspective helps avoid the myopic thinking of the nutritional mainstream as exemplified in Diet Cults.

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Paleo lifestyle enthusiast, Minimalist runner

One thought on “Review of “Diet Cults” by Matt Fitzgerald”

  1. Excellent review. I find the skepticism about so-called “alternative diets” pretty precious. We know that the nutrient content of most raw foods has dropped dramatically in the last fifty years, whether that’s because the iodide is gone from the soil where most of US lettuce is grown (for example), or the prevalence of antibiotic use in cattle in feedlots kills off the bacteria that would transfer b12 to their tissues.

    And there’s the things we’re actively doing: wheat flour is sprayed with folic acid and cyanocobalamin to prevent neural tube defects, for example, and compensate for the loss of the natural vitamins through processing. But that can lead to starvation states for folate and b12 in the people consuming high wheat diets.

    So when people talk about the SAD as some kind of “standard” instead of just an historical accident, at best a product of imperfect information and at worst a conspiracy to supply the cheapest calories for the highest profit, its a pretty poor excuse for clear thinking.

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