I take it for granted that I know better than to believe everything I read or hear; and that the people I know, work with, and choose to spend my time with are critical thinkers too. I shouldn’t take it for granted. The reason that I’m writing this post? Because I just watched Forks Over Knives and am feeling upset that it’s full of misinformation… and that people are watching this and swallowing it whole. A girlfriend just came back from a summer in Wisconsin proclaiming the benefits of a vegan diet, touting this book as her life-changing guide. I had eggs for breakfast. She had two donuts. I guess that’s what happens when you put a paleo and a (confused) vegan in the same breakfast booth. They judge each other and both feel right.
I’ll never forget the moment that I was taught to think outside of the published word. I was sitting in a freshman biology class at Reed College and the professor told us to open up our biology textbook and turn to a specific page. “See that bottom right paragraph?” he asked us. “Cross it off. That’s no longer true.” Then: “Turn to page 187,” he said, “and I want you to tear out the next two pages. Tear it out,” he said, “it’s wrong.” I was shocked. Horrified. This is a book! I wanted to protest. Tear it out!? I had stupidly (oh, to be 19 years old) assumed that if it had been published in a book it was accurate and true. Right? WRONG.
My issue with Forks Over Knives? They take a reductionist and outdated view on animal products. This book prescribes to the same misguided logic that proclaims that you’re better off eating a KFC Double-Down than a single egg. What? They both assume that dietary cholesterol increases blood cholesterol levels and therefore eating cholesterol-containing foods causes heart disease. The problem with this? Dietary cholesterol only contributes a tiny amount to your blood cholesterol — about 70 percent of your cholesterol is actually made by your liver. If your body isn’t busy producing too much of its own cholesterol, then eating cholesterol really isn’t a problem. (If you’d like a great guide to cholesterol, check on Mark Sisson’s Definitive Guide to Cholesterol.)
The world used to be flat, people! Well, not really, but it might as well have been for all the people who believed that it was.
To bring this back to Forks Over Knives, what I do appreciate about this book is that it encourages us to think about the foods that we’re putting into our bodies. It attributes most disease to diet. I agree. I absolutely agree. But I’m not so sure that they’re right that a vegan diet is the best way to go. Forks Over Knives vilifies processed foods (I agree) and then lumps in animal food products, too. I’ve got a problem with this. Why? Because, for instance, they relied upon studies that fed casein (a protein in dairy products) to rats to explore whether or not protein is bad. This is a seriously flawed study. Many people are allergic to dairy and have serious problems with casein, much like at least 1 in 133 of us have trouble with gluten. Casein causing health problems is not the same thing as a steak causing health problems, or egg yolks causing problems, or clarified butter causing problems. All their study showed is that feeding a diet of 70% casein to rats caused health problems in rats. Forget protein in people in general.
My takeaway? Think for yourself. Consider the number of conflicting studies you’ve seen in your lifetime and take each subsequent study you see with a (huge) grain of salt. And where diet is concerned, consider a self study to see what really works for you. And a note on that: You have to eliminate any given food for about 21-30 days until you’ll know if it adversely affects you. You’ll also have to test each food individually so that you can be sure that you understand what food specifically is causing problems. If you want a little structure to help you explore diet and its effect on your health, the Whole30 from Whole9 Life is a great place to start.
UPDATE: Turns out this post is timely. Now, another study comes out: Egg Yolks Almost as Bad as Smoking. See Mark Sisson’s smart response here; but to summarize, the study was conducted by three scientists, two of whom have ties to the statin industry (conflict of interest?); and the study failed to take confounders such as waist circumference, age, smoking, blood pressure, stress, etc. into account.
Correlation is not causation–and any study that uses observational data to “prove” something without isolating the factor being tested hasn’t proven anything at all. In fact, along those lines, this study, this study, and this study all found that there was no correlation between consuming egg yolks and high cholesterol.
Now what? (Another shout out to Reed College: My professors frequently gave us five to six conflicting articles, all citing “facts,” and then asked us to discuss. After triggering a slight existential crisis, this method of teaching taught me to ask good questions and be critical of everything I read.)
Where egg yolks versus smoking are concerned, maybe we should be asking more questions than we should be accepting “answers,” and do a little more thinking for ourselves instead of turning to the news for diet advice.