A few months ago, I took on a personal experiment in the form of a plant-based diet, based on the compelling film, Gamechangers. I followed the diet for about 3 weeks, and during that time had good results: perceived increases in strength and endurance, and a slightly slimmer waistline. But I’ve since abandoned the experiment and come to believe that the optimal human diet includes animal protein – but with some major caveats.

As I wrote in my original post, there is a tremendous amount of conflicting information out there, when it comes to diet and nutrition. Determining the credibility of information on any topic in this day and age is extremely difficult. This holds especially true with diet and nutrition, perhaps because food is one of the largest economic markets in the world, estimated at nearly $4 Trillion in 2020. But I’ve come to appreciate the approach of thoughtful scientists like Chris Kresser, who explains his methodology in an entertaining and informative debate with Dr. Joel Kahn on an episode of the Joe Rogan Experience. I maintain a bit of skepticism with regards to Chris, especially since a couple of his recent podcast episodes have a bit of a product shill to them (still, pretty convincing; I bought some). But I generally agree with his scientific approach to seeking truth.

So, about those caveats:

1. Not all animal protein is created equally. Even when excluding meats fried in oil (see below) and restricting the comparison to just grilled or roasted cuts of meat, free from marinades and other toppings, the difference between grain fed and grass fed meats is pretty significant – and entirely non-obvious! My current understanding is that the feed of traditional meat animals includes a lot of industrial seed oils, taking the omega-6 content of their meat up to unhealthy levels. Grass fed meats, on the other hand, are higher in omega-3 fatty acids. 
2. Conventional meat animals are typically given significant amounts of hormones and antibiotics, to boost “yield” (the amount of sellable meat per animal) and offset the risks of farming practices that would otherwise make the animals very sick. These hormones make their way into the meat that humans consume, and are not optimal for human health (to say the least).
3. Almost all prepared foods – whether meat or vegetarian, whether sold in a restaurant or in a grocery store – contain industrial seed oils, which I’ve come to believe are at least as bad for human health as my previous enemy #1, sugar. Check out Chris Kresser’s article on these ubiquitous food additives and see what you think. Industrial seed oils are commonly listed on labels as soybean, canola, sunflower, safflower, peanut, vegetable, etc – basically any oil that’s not olive, avocado, coconut or tree nut (cashew, macadamia, etc). If seed oils really are as bad for us as Kresser believes, it’s no wonder we’re seeing record levels of obesity and chronic disease.

So what’s my diet now? It’s pretty simple. As much as possible, I eat whole foods that I prepare myself, in reasonable macronutrient proportions (protein/fat/carb), during a 6-8 hour “feeding window” each day to keep with my intermittent fasting regimen. I don’t pay any attention to the quantity of food I eat during that window, and I certainly don’t count calories. I could probably optimize my diet another 10% by really dialing in the macro proportions. But that’s a lot of work for a relatively small incremental benefit. Basically, I’ve arrived at Michael Pollan’s common sense prescription from The Omnivore’s Dilemma: “Eat food, not too much, mostly plants [by volume, not calories].”

Many thanks to JB for turning me on to the Kresser/Kahn debate and other good info from Dr. Peter Attia.

I’ve been voluntarily vegetarian (and mostly vegan) for two weeks now. Let me say right off the bat that I welcome any compelling info regarding canivory, veganism, nutrition, etc. I generally try to base decisions on first principles. But there is so much conflicting information on diet and exercise out there (and all of it so convincing! except maybe this one) that it’s basically impossible to separate signal from noise. I’ve tried ‘em all: Paleo, Zone, Keto. Was even tempted by GoMaD at one point. I do time-restricted eating, aka Intermittent Fasting. And I’ve been curious about plant-based diets (PBDs) for years now. I had concluded that a PBD is probably optimal if your top goal is longevity. But I had assumed the cost of those extra years was athletic performance, lean muscle mass, etc. Now, I’m no elite athlete – far from it. But I do like to push my limits. And I figured I could always make the switch to a PBD later in life when being active and pushing myself wasn’t as important to me.

What finally got me off the fence was the movie Gamechangers, a documentary hosted by UFC fighter, James Wilks. I’m a sucker for documentaries anyway. But this one really got me. Where other veg-docs have stressed the environmental or general health benefits of PBDs (Cowspiracy, for example), Gamechangers addresses athletic performance head-on. I nearly wrote it off in the first 5 minutes, as it started off featuring a sinewy ultra-marathoner (400m is plenty, thanks). But then it featured a world-record strongman, an olympic weightlifter, and a bodybuilder – folks with more than enough lean muscle mass supposedly packed on through hard work and vegetables. The film highlights plenty of pro-veg science. But then again, the meat industry has plenty of pro-meat science too. Still, the film made me PDB-curious enough that I decided to seek some first principles the only way I can in this case: to self-experiment.

At two weeks, it’s obviously way too early to call. But I can confidently report the following:
1. I have plenty of energy. Truthfully, I feel especially energetic. But I’m going to tip my hat to the placebo effect and say no more than that I have noticed no decrease in energy levels.
2. My bodyweight workouts (pushups, pullups, airsquats, etc.) have not suffered. The empiric evidence is that my performance has actually improved. But again, there are other factors in play: I might weigh less from a likely calorie deficit, making bodyweight workouts easier. And/or, I could just be improving naturally from doing workouts on the regular. So I’ll simply say that I have not noticed any reduction in strength.
3. The food has been delicious. Our staples are rice, lentils, baked potatoes, pasta marinara, salad, fruit, and nuts. I do still find the smell of grilling meat appetizing (and there’s plenty of that here, in the land of carne asado). But I haven’t craved meat like I thought I would, and I haven’t gotten bored with our mostly-vegan fare.

I imagine a behavioral change as big is this would be very difficult if those around me were still eating meat. Luckily, Dallas led the charge, followed by Julia, and finally Dana and me. We are encouraging each other remotely, although none of us has really needed much encouragement. I keep reminding myself that this doesn’t have to be forever, nor does it have to be all-or-nothing, as most diet advocates would have me believe. But as long as I continue to feel good and don’t detect any drop in strength or energy, this experiment might just become something a little more permanent.