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From Vegan to Keto: Myths About Nutrition

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Q: I want to eat healthy. How do I sort out the marketing hype from the science in the diet wars? 

— Kurt, Seattle

A: The original title of this article was going to be “The Trouble with Vegans.” It was provocative and catchy, which certainly would have prompted a lot of people to read it.

But the “trouble” with vegans isn’t confined to vegans. It’s really the trouble with nutritional politics, which have become as partisan and divided as Congress. Facts matter little, allegiance to your nutritional orthodoxy take precedence over science, and if you’re on the wrong “side” of things, you’re not only stupid and uneducated, you’re also morally bereft.

So this article is really about the marketing claims made for popular diets, misconceptions about things like “vegan” and “keto,” nutritional politics, and “know-nothing” science. I’ve been accused many times of being antivegan; what I really am is antimisinformation.

Let’s see if we can sort out some of the myths, truths, and misconceptions in the diet marketing wars, and come up with some basic, non-partisan facts we can all agree on.

The Vegan Myth

A vegan diet is defined by what’s not in it. As long as you don’t eat foods that once had a face, you can be a vegan. Vegans make all kinds of recommendations for foods you should eat, but the fact is, you can eat a 100 percent junk-food diet and still be a vegan as long as it meets the single requirement: no animal products.

So let’s bust myth number one: A vegan diet is not by definition healthy—it’s just a diet without animal products.

Personal story: I’m a fan of the pizza pie. It’s my one non-low-carb food vice. Recently I grabbed a slice of what looked like a gloriously cheesy pizza from the self-serve section at Whole Foods, and when I took a bite of it I thought I had been poisoned. Every molecule of my health-aware consciousness said, “Bad. Food. Abort. Mission.” I took it back to the counter, only to find that it was the “vegan pizza.” I asked for the ingredients, and what I saw confirmed my worst suspicions. This was a chemical stew of unpronounceable ingredients, fake flavors and texturizers, chemical stabilizers, extracted soy proteins, and a baker’s dozen of things no self-respecting health fanatic would go near. I did a similar inspection of the ingredients list for vegan donuts, vegan “chicken,” and vegan “turkey.”
All I can say is—if you do eat this stuff, don’t read the ingredients list or you’re likely to experience a serious amount of cognitive dissonance.

But let’s say you do veganism as it was intended to be done, with an all-whole-foods, plant-based diet rich in nuts, berries, and vegetables. You’re not out of the woods yet, because you have to make sure your diet is healthy. You can’t get everything you need from a vegan diet.

Those who say you can are not informed by science, they’re just sticking to the party line. Despite claims to the contrary, there’s no B12 in plant foods. There are what’s called B12 analogues in plants—molecules that look suspiciously like B12 but behave differently in the body. Vegans are very likely to be underconsuming iron, selenium, zinc, and omega-3 fatty acids. Vegans will argue, “but there’s iron in spinach!” and they’re right—but it’s not the same iron that’s found in beef. Beef has heme iron—the most absorbable and usable form of iron. Spinach does not.

Then there’s the omega-3 issue. Yes, there are omega-3s in plant foods, but the omega-3 in plants (alpha-linolenic acid, or ALA) is not identical to the omega-3s found in fish and grass-fed beef. The two that come from fish—EPA and DHA—have been the most extensively researched, and are the ones that are ready to do their magic in your system. On the other hand, ALA has to be converted to EPA and DHA, which the body can do, but doesn’t do very well.

So vegan omega-3 and animal (fish) omega-3 are not the same thing. If you’re a vegan and relying solely on flax, chia, and hemp for your omega-3s, that’s fine. But be sure to double (or triple) your dosage, since only about 10 percent at best is going to wind up as DHA and EPA.

The Keto Conundrum

Keto diets come with their own set of myths, starting with this one: You can get everything you need on a keto diet.

You can’t—at least if you believe that fiber is important, and not all keto advocates do.

I think the enormous amount of emerging research being conducted on the health of the microbiome (the ecosystem of bugs and other microbes that live in our gut) shows overwhelmingly that fiber is one of the most important (and neglected) parts of our diet. And it’s a myth that you need to eat grains to get it. There is fiber in fruits and vegetables, including some that you wouldn’t think of as fiber heavyweights (like avocado!). Most people just don’t get enough. That’s why I recommend fiber supplements for everyone (but especially those on keto).

The other myth about keto is that it works for everyone. It doesn’t. Genetics may offer a clue as to why that’s so, but that it’s so is indisputable. The Paleo-friendly nutritionist Esther Blum, MS, RD, author of Why Cavewomen Don’t Get Fat, has told me numerous times that her female clients just don’t do all that well with keto. One reason might be a variation of a gene called ApoE2. People with a certain variant of that gene thrive on fat—they have the enzymatic machinery to break it down, and their metabolic pathways are primed to extract every nutrient. Others have a variant of the gene that produces the opposite effect, and these people feel dreadful on a high-fat diet. Once again, it’s confirmation of my basic thesis in nutrition: everybody’s different.

Another myth is that vegan and keto are polar opposites. They’re actually not. You get most of your calories from plant-based fats like coconut oil, extra-virgin olive oil, and Malaysian palm oil; you get your protein from vegan sources; and you eat a ton of vegetables.

Still confused?

Diet programs in the age of the internet are a black hole of promises and marketing claims, with only the most casual relationship with the science on which they claim to be based. And one of my missions in life is to dumb it down and leave people with some basic nuggets that can help them navigate the diet wars and sort out marketing hype from actual science.

Here’s the one nugget that I’d like you to take away from this article. It’s advice that’s “diet-agnostic,” the ultimate nonpartisan principle that will actually work for everyone. (I know I implied that there’s no one program that works for everyone—this is the exception, and you’ll see why in a moment.)

Eat Whole Foods

Keto, vegan, South Beach, Atkins, raw food, Paleo, Primal, or low-fat—what matters most is that you eat real food, and you eat it in its natural, unprocessed state.

Imagine that you were naked on the African Serengeti with a sharp stick for a weapon. What could you hunt, fish, gather, or pluck? Those are the food groups.

Vegans do have one thing right: the meat we get in this country is a toxic waste dump of hormones, antibiotics, steroids, and bad fat. It’s known as “factory-farmed meat,” and it comes not from real farms but from huge behemoth factory-type operations where cows are confined, fed acid-producing grain, and basically live horrendous lives and produce disgusting food. If that were the only kind of meat available to me, I’d become a vegan myself. But it’s not.

If you look for it, you can find 100 percent grass-fed beef, pastured pork, and truly
free-range (not fake free-range) chicken and eggs. Those are very far from the “meat products” that vegans correctly demonize. Those foods are health foods, and they’re very close to what you’d eat if you hunted down game every day like your Paleo ancestors.

In fact, if you choose your diet from foods that could be hunted, fished, plucked, or gathered, it won’t matter as much what diet you’re on. It won’t matter as much what proportions of fat, carb, and protein you consume, nor how many calories. In terms of health, those are the four basic food groups that fed the human genus since our homo-sapiens predecessors first roamed the earth 2.4 million years ago. Those are our “factory-specified” fuels.

Healthy tip!

If you choose your diet from what can be hunted, fished, plucked, or gathered, it won’t matter much which diet you’re on.

Keto, vegan, South Beach, Atkins, raw food, Paleo, Primal or low-fat—what matters most is that you eat real food, and you eat it in its natural and unprocessed state.

Start with that premise and you’ll do just fine, no matter what dietary program you decide to follow.