Is A Vegan Diet Best For Athletes?

A plant-based diet can be a fine way to eat, whether you’re an athlete or not. A Netflix documentary called Game Changers argues that it’s not just fine, but that it’s better and that meat is harmful in some way. That’s not what most nutrition experts say, so let’s take a look at the claims in Game Changers and what you should know about vegan nutrition and training.

True: You can get plenty of protein and nutrition from a plant-based diet

Early in the movie, experts appear and debunk a host of myths about vegetarian diets. If you came into this believing that a vegan or vegetarian diet cannot be healthy, this is valuable stuff (although I don’t know how common these misconceptions really are). A few things that the movie correctly points out are true:

• Protein doesn’t give you “energy” for endurance exercise (although it is helpful for building muscle)

• Vegan diets can provide plenty of protein

• You can get high quality protein from plants

These statements come with some caveats, but they’re true and the bottom line is that there are plenty of vegan athletes out there doing quite well.

Vegan protein sources will almost never match the protein-to-calorie ratio of meat, so you’ll need to eat more food to get your protein in. That’s fine if you’re a cyclist or ultra runner, because you’re consuming tons of calories to fuel your workouts. If you need a lower calorie intake, like if you’re losing weight or if you’re a strength athlete who needs a lot of protein relative to their calories, you’ll probably need a plant-based protein powder.

The movie gives an example of four foods that it says contain roughly equivalent amounts of protein. Here are the numbers, and you can decide for yourself whether these are comparable food items (I think the comparison is a bit iffy):

• 1 cup of cooked lentils: 18g

• a peanut butter sandwich: 15g

• 85 grams of beef: 22g

• three large eggs: 18g

If you take the approach that there are many ways to build an effective diet for athletes, and that sticking to plant-based foods is one of those many ways…none of this seems very surprising. And that is, in fact, the position of the Academy of Nutrition and Dietetics, the American College of Sports Medicine, and others. There is, however, no compelling evidence that vegan diets are better for athletes than omnivorous ones.

False: we were “meant” to eat vegetables and not meat

Disappointingly, there’s a section in the movie that repeats some inaccurate and misleading tropes about how our bodies are built.

Yes, we have longer digestive tracts that carnivorous animals; but we also have shorter digestive tracts than herbivores. Yes, we have molars that don’t match those of carnivores; but our teeth aren’t specialised to plants, either.

And sure, we have three-colour vision while most mammal carnivores do not—but neither do most mammal herbivores. Humans are clearly equipped to eat both plants and animals, and that’s not even controversial among scientists. This segment was just silly.

False: a vegan diet alone can make a good athlete into a great one

Movies are stories, carefully scripted and edited, even if they are non-fiction. Think about reality shows: they’re “real,” but you know the producers have put a lot of effort into constructing a storyline based on what they want the finished product to convey.

So, think about that when you see the movie’s stories about plant-based athletes. Maybe they switched from eating a lot of fried chicken to eating vegan meals, but is that responsible for their success? Probably not. It’s great that Kendrick Farris went to the Olympics, but so did tons of meat-eating weightlifters.

Anytime an athlete goes from struggling to successful, it’s a safe bet that they changed many things about their life and training, not just one. If you’re motivated enough to change up your diet, you’re probably motivated enough to question your coaching, your training time, your rest days, your weight class, and everything else that could potentially affect your success. Not to mention, when athletes in untested sports talk about how they got “stronger and bigger”…there’s always the possibility they are taking more than just plant-based protein powder.

False: the studies cited at the bottom of the screen provide solid support for what the narrator is saying

I couldn’t go down every rabbit hole of scientific sources for this movie, but the dives I took were always very unsatisfying.

For example, there’s an “experiment” (more of a demonstration) in which three athletes eat meat-based or plant-based burritos, supposedly to demonstrate that meat inhibits endothelial function in the blood vessels.

When the narrator talks about what this means, seven studies appear at the bottom of the screen.Rather than comparing the effects of beef and chicken versus beans and avocados on blood triglycerides, they include studies about grape juice, chokeberry juice, blueberry flavonoids, cocoa, and tea. Meanwhile, a quick google finds studies like this one showing a beneficial effect of ham on endothelial function. Meanwhile, the study they claimed shows a beneficial effect of avocado on blood lipids actually compared hamburgers with and without avocado, rather than a meat versus a plant-based meal.

Layne Norton, a bodybuilding coach with a doctorate in nutritional sciences, sums up the demonstration this way:

[the scientist who conducted the demonstration] spoke at length about the endothelium and vasodilation but then did not measure ANYTHING pertaining to vasodilation or endothelial function. The reason the serum from the meat eaters was cloudy was likely because those burritos contained more total fat. Fats from the diet are packaged into chylomicrons which cause the serum to appear cloudy after a high fat meal.

In another typical example, the movie claims that ancient Roman gladiators ate a plant based diet of mainly beans and barley. But the actual research on which that claim is based states that the analysis cannot say for sure how much meat the gladiators ate.

True: there is an undeserved relationship between meat and manliness

This is a stereotype that has always bugged me. People of any gender can eat meat, or eat vegetables. People of any gender can be strong. So I applaud the film for its work breaking down the stereotype and letting men just eat some freaking vegetables in peace. If you need to hear Arnold Schwarzenegger say it before you’ll believe it, then the Game Changers has you covered.