No longer vegan

After several years, I’ve decided to experiment with a non-vegan diet.

My knowledge of nutrition has grown, the available evidence has evolved, and my own goals and needs have shifted.

I’m treating this as a 30-day experiment, and then I’ll reassess.

If you’re curious, here’s a closer look at what led to this decision and how I’m approaching it.

How I became a vegan

I had been meaning to adopt a vegan diet for a long time. I tried various approaches in the hope of becoming healthier: I practiced intermittent fasting, followed a low-carb diet inspired by Gary Taubes (author of “Good Calories, Bad Calories”), and relied on whatever evidence-based guidance I could find amidst the usual nutritional confusion.

I later learned that the scientific basis of healthy nutrition was shaky at best, so I kept experimenting in search of something better.

The search ended when I found Michael Greger’s excellent book How Not to Die. In that book, as well as in his other works, How Not to Diet and How Not to Age, Greger argues convincingly that a vegan diet is incredibly healthy and, for most people, the healthiest way to eat.

So I switched to a vegan diet, and honestly, thought I had the diet part of my life figured out: my health was excellent, I felt energetic, and my blood markers were good. I’d continue to optimize other aspects of my life, but not my diet. Although I tried to maintain a healthy skepticism, it was hard not to feel like I had this one figured out.

Maybe I was right, and a vegan diet is the best. It’s just tough to follow while pursuing the goals I have now.

Those goals fall into three (interrelated) areas:

1. Strength training and overall fitness
2. Managing hemochromatosis (iron overload)
3. Cutting body fat and lowering LDL

They’re all entangled, but strength training and fitness drive the other two. So let’s start there.

Strength training and veganism

Let me get this out of the way: you can be vegan and strong, really strong. There are great examples of high-performing athletes, including the vegan strongman Patrik Baboumian.

What I don’t think you can do, though, is be vegan, really strong, and not either 1) rely on a lot of supplements, or 2) stay in a perpetual bulking phase.

This, I think, is a core deficiency of Michael Greger’s evidence-based dietary advice: his recommendations around protein intake differ significantly from those of other notorious experts .. and most people building muscle for that matter.

In particular, Peter Attia’s “Outlive” and Greger’s “How Not to Age” seem to present opposing views on the role of protein quantity in health and longevity in an almost comical fashion.

Greger writes:

Evidence that protein restriction extends lifespan actually predates the evidence from studies using caloric restriction. Data on the relative importance of protein versus caloric restriction are mixed, but a comprehensive comparative meta-analysis of dietary restriction of more than a hundred studies across dozens of species found that when it comes to life extension, protein reduction was more important. […] To help slow this aging pathway, on a daily basis, consider: striving to stick to the recommended daily intake of protein of 0.8g per healthy kg of body weight (0.36 g per pound), which translates to about 45 g a day for the average-height woman and about 55 g a day for the average-height man.
— Michael Greger, How Not to Age (p. 571)

Attia, on the other hand, writes:

The first thing you need to know about protein is that the standard recommendations for daily consumption are a joke. Right now the U.S. recommended dietary allowance (RDA) for protein is 0.8 g/kg of body weight. This may reflect how much protein we need to stay alive, but it is a far cry from what we need to thrive. […] How much protein do we actually need? It varies from person to person. In my patients I typically set 1.6 g/kg/day as the minimum, which is twice the RDA. […] So if someone weighs 180 pounds, they need to consume a minimum of 130 grams of protein per day, and ideally closer to 180 grams, especially if they are trying to add muscle mass.
— Peter Attia, Outlive (p. 331)

So one doctor says “eat 55 grams of protein,” and the other says “eat 180g.” That’s a huge difference! They can’t both be right for the same set of goals.

But the truth is, on an all-natural (no-supplement) vegan diet, it’s virtually impossible to eat 180 grams of protein without also consuming a ton of calories. Your diet would be 3,000 to 4,000 kcal worth of beans, tofu, lentils, whole grains, and vegetables every. single. day.

That’s a point Gabrielle Lyon makes in Forever Strong, a book I don’t quite place at the same caliber as the ones I quoted above, but one that, in my view, gets this part right.

[From a Diagram] There are 24.5 grams of protein in:
- Beef: 136 Calories (3 ounces)
- Quinoa: 666 Calories (3 cups)
- Peanut Butter: 632 Calories (8 tablespoons)
- Black Beans: 409 Calories (1 cup)
- Edamame: 244 Calories (1.3 cups)
– Gabrielle Lyon, Forever Strong (p. 127)

It’s a huge difference, and while she exaggerates on the beef, this is the equivalent of calories for chicken breast or tilapia. To get the same amount of protein from plant-based options, the caloric load is often 2x to 5x higher. And when you’re aiming for 180+ grams of protein a day, that’s impossible without heavy supplementation.

Which is why Michael Greger can’t offer this within the bounds of his plant-based framework: to get 180 grams of protein from black beans alone, you’d have to eat around 2 kilos (~4.5 pounds) of cooked beans per day, which amount to about 2,600 calories, not counting anything else you eat!

This wasn’t as much of a problem when I was bulking, as I was gaining both muscle and weight. But now that I want to lose 10 pounds while maintaining muscle, this changes. For someone at my body weight, that means eating 180 to 220 grams of protein per day.

And that left me with two options:
1. Drink 3–4 vegan protein supplements per day
2. Eat meat

But I just wasn’t up for going from one shake a day to three or four. That’s not sustainable for me, not in the long term.

And that led me to another critical factor: controlling hemochromatosis, or iron overload.

Hemochromatosis control

Hemochromatosis is a condition in which the body absorbs and stores excessive amounts of iron, often to toxic levels. Over time, excess iron can accumulate in organs, especially the liver, heart, and pancreas, leading to toxicity, organ damage, and, if left unmanaged, even death. Like many others, mine is genetic.

Controlling iron intake on a high-protein diet can be challenging because many protein sources are also rich in iron. That includes red meat, dark poultry, fish, beans, lentils, tofu, whole grains, leafy greens, and seeds. Whether animal-based or plant-based, it’s hard to consume high amounts of protein without blowing past my iron limits.

It also happens that the vegan protein shake I drink, which is great in almost every respect, is high in iron. That’s common for vegan shakes, since they’re often derived from iron-rich plants. So if I were to move to a 3–4 shakes-a-day routine, I’d need to switch supplements and find a new one I like the taste of.

So I found myself with a rough set of options:

• Drink 3–4 shakes a day, which felt excessive, and try to find a new vegan shake that was lower in iron but still effective and palatable
• Lower my protein intake to around 80–100 grams instead of 180g+, just to keep iron levels in check, but losing muscle
• Rely more heavily on plant-based whole foods, drastically increase calories, stall fat loss, and risk even more iron intake from legumes, soy, and grains
• Eat meat, low-iron options like chicken breast and white fish

While heme iron from meat is more readily absorbed than plant-based iron, you can still hit high-protein goals with low calorie and low iron intake by choosing specific meats like chicken breast and tilapia, something that, with plant-based diets, is only realistically achievable through heavy supplementation.

To hit the same protein target with black beans instead of chicken breast or tilapia, I’d absorb about 3 times more iron, consume 3 times more calories, and have to eat over 3 times more food.

All of this ties directly to my goals of reducing body fat and lowering LDL.

Cutting body fat and lowering LDL

A high-protein, plant-based diet that doesn’t rely heavily on supplementation is, by necessity, a hypercaloric diet. And under that kind of diet: • I gained fat alongside muscle • My LDL and other markers, like triglycerides, increased

Interestingly, the only blood marker that’s ever been out of range during my vegan diet was triglycerides. And I suspect that was largely due to consistently eating in a caloric surplus. I’m sure it could have been brought under control if I had eaten far fewer calories and much less protein, like many vegans do.

It’s relatively well-studied that vegans have lower LDL levels than omnivores, but I think that’s only possible at significantly lower levels of protein intake as well.

So to lose fat, lower LDL, and maintain my weight and muscle, I need a much higher protein-to-calorie ratio than what’s realistically possible through a regular vegan diet.

Again, I think it’s entirely possible that heavy plant-based supplementation could overcome this limitation, but that brings me back to the same fork in the road:

Given my goals, I chose to eat meat instead of drinking 3–4 vegan supplement shakes a day and staying vegan.

Final Thoughts

This is simply an adjustment to better align my diet with my current goals. One close friend of mine is both strong and vegan, and makes it work well with supplementation and proper tracking, so I know it’s possible.

I may return to an entirely plant-based approach at some point, perhaps with improved supplementation, more tofu, a fresh strategy, or a combination of all of the above. Perhaps it’s more sustainable when I’m maintaining instead of cutting, for example.

But for now, this is the experiment.

Just as I did when I first went vegan, I’m giving it a 30-day trial.

And then I’ll reassess.