Iron Strong Health Reviews: "The Game Changers"
The documentary, The Game Changers, released in 2018 and explores the unconventional dietary patterns of a select group of elite athletes and the potential benefits of swapping out meat for a plant-based diet. The film begins with the story of James Wilks, a UFC Welterweight champion who, near the height of his MMA career, was left injured and sidelined for nearly six months. During that time, he explored sports science and nutrition that led him down the path of plant-based eating. The documentary then details the achievements of world-class athletes who follow a plant-based diet from Olympic sprinters and power lifters to ultramarathon legend Scott Jurek, to Patrik Baboumian who holds numerous world records in carrying and lifting very heavy things.
The synopsis describes this as a journey to find "the truth about meat, protein, and strength." So how well does this film deliver on this quest for truth and do the arguments presented suffice for reason enough to change your dietary habits?
Well, for one thing, if any single documentary or blog article are enough to upend your dietary trends, I would challenge you to select a different critical thinking cap from your closet with a more robust construction. I also don't think it's entirely fair to hold any documentary director to provide a scientifically well-rounded, air tight case for human diet within a two hour time window. With that said, I'm going to address some of the biggest things that stuck out to me, so below is not necessarily a comprehensive list of their arguments. With that aside, let's dive into some of the stances the film takes and what my take on each of them are. If you haven't seen it yet, I would recommend the film, and I would recommend a critical thinking cap along the way.
Premise 1: You don't need meat to satisfy your protein needs.
The documentary takes a significant amount of time trying to explain that plants do in fact contain all essential amino acids for human function. It offers anecdotes about how vegan powered athletes have beaten their meat eating counter parts and put them to shame. It challenges the societal norm that men aren't as manly if they don't eat copious amounts of meat and steak. There are a few demonstrations of what happens when you compare blood plasma samples of NFL athletes 24 hours after eating a burrito with either beef, chicken or rice and beans. The viewer gets to see how clear the blood plasma is after eating fully plant based and meat based. They convince the viewer that this is "quality" meat, even. "Organic chicken" and "grass-fed" meat.
It bothers me that these terms automatically equal "quality." "Organically" fed chickens don't mean the chickens had good lives, eating a diet full of grasses and bugs like a natural chicken would have eaten. A chicken can be considered "organic" if it ate "organic" corn all it's life but is still confined in a tiny cage, hampering its natural growth. This has profound impacts on the true quality and inflammatory effects of the end product. The same goes with beef. All feedlot cattle can be considered "grass-fed" because at some point in its life, it was, but "grass-finished" is the gold standard of good beef. The last few months of a cows life on a concentrated animal feeding operation takes the poor animal down a very unhealthy path, eating a diet of corn-based feed and living in an environment that produced excessive stress hormones on the animal, leading to a much more degraded end product.
There are some fancy graphics that demonstrate how all of your animal protein must originate from plants to begin with, so on a chemical (and surface level), why shouldn't the human be able to acquire all they need from plants? Patrik Baboumian tells of how people are amazed, asking him, how can you be as strong as an ox just eating plants? To which he retorts, "what do you think the ox eats!?"
So, there was a lot to unpack there and I believe the film makers take some liberties here. As they're deconstructing the idea that we must get protein from meat, they also throw in a lot of other arguments that don't get their fair share of attention and analysis. If they were to just explain that our bodies must consume 9 different amino acids to be fully nourished in the areas of protein and that a fully plant-based diet can satisfy those, I wouldn't have too much more to add. I agree that those amino acids all exist in the plant kingdom, although they take for granted the fact that many humans have adverse responses to eating certain plants. Never mind that, their select group of high performing athletes don't seem to have that problem so let's keep the focus on them...anyway, did they succeed in at least presenting a valid argument that there is a possibility that we can keep muscle mass while eating plants? Sure, I think it's valid, but there were a lot of assumptions that this is good idea for everyone.
Premise 2: Humans are designed to eat plants instead of meat
This one was a little more loosely explored and most of the assertions came through soundbites from various doctors and scientists.
Claim 1: The length of our digestive tract is longer than carnivores, therefore, our digestive systems were designed for plant breakdown more so than animal breakdown.
They threw up a basic infograph to show the difference in digestive tract length of humans compared to carnivores and indeed, some carnivores do have shorter digestive tracts relative to body length than humans do. But that doesn't tell the whole story. Humans have the same intestine to body length ratio as elephants but it's still far lower than ruminant animals like horses and cows. Plus, there are exceptions. Pandas and sloths, both vegans, have relatively much shorter intestines than other plant eaters. (Panda's intestines are 4.5x the length of their body and sloths come in at 3.3.) Conversely, dolphins and seals have digestive tracts that are upwards of 30x their body length, even longer than some ruminants. 
So, the idea that digestive tract length shows that we're meant to eat plants instead of meat is not a reasonable conclusion.
Additionally, plants have a lot of built in defense mechanisms for predators. Aside from fruits, plants don't "want" to be eaten! We've identified a family of compounds referred to as "anti-nutrients" that bind to minerals and hamper nutrient absorption. Once bound to a mineral, these molecules damage the small, hair-like "microvilli" that line our digestive tract. Celiac disease is an extreme example of the damaging effects of anti-nutrients on our gut, but all humans have some amount of intolerance to them.
Wheat and legumes are particularly high in anti-nutrients, especially the strains of wheat we've genetically modified in recent years for their drought resistance and high yield, not for human health. The film makes no mention of these problems and seems to lump wheat-based products as part of a perfectly healthy human diet that we were clearly designed for.
Claim 2: You have to obtain vitamin C from plants.
I mean, right off the bat, this is not an argument against meat. A primal-aligned diet that includes meat, fish, foul, eggs, some fruit and plentiful vegetables will well satisfy their need for vitamin C. But I think what they were getting at is that humans had to rely on some amount of plant food as we developed as a species because we had to consume vitamin C. While it's true that we cannot produce vitamin C endogenously and must obtain it from diet, it's not true that you can't get enough from animals.
If you include organ meats in you diet, as our ancestors certainly did (you only have to go back a few decades to see that!), you have more than enough vitamin C to satisfy your needs. In fact, you'd only need to consume about 4-5 ounces of liver to ward off scurvy, a disease caused by vitamin C deficiency.
Furthermore, if you are eating a high meat diet, you're not taking in as many carbs as a result. Our cells use the same pathway to absorb carbohydrate energy as they do vitamin C. Think of it like a one lane bridge where only two types of car can cross over and there is a set number of cars that can pass on a given day. Carb molecules and vitamin C molecules use the same bridge, so when you remove the carbs, the cell can absorb more vitamin C and your daily requirements actually end up going down.
Claim 3: Your brain runs on glucose. Glucose comes from plant food. Therefore, we must eat plant food.
The soundbite didn't go much further than that but it came from a man in a lab coat, so that must be the end of the story, right? Well, there are two major assumptions in these premises.
1) The assumption is that your brain *only* runs on glucose and 2) that glucose can *only* come from plants. Both of these assumptions are wrong as we'll see.
Your brain is a hungry organ and can use up as much as 20% of each day's energy, a highly disproportionate amount. And it cannot uptake free fatty acids (FFAs) from the bloodstream because of something called the blood-brain barrier. This barrier ensures that only specific molecules can reach your precious brain and FFAs are too large to fit, but glucose molecules are not.
It is true that your brain has an absolute requirement for glucose each day of about 120g. There is no escaping that. However, the brain is also very good at burning an alternative fuel source called ketone bodies. These are produced in the liver and produce far fewer free radicals when metabolized, and the argument can be made that these are the body's preferred fuel source (that's another story). When an individual has been eating a higher-fat diet for a sufficient amount of time, the brain starts to shift it's fuel source to ketones and the absolute glucose requirement can even go down.
When glucose levels are low from eating a high fat/higher meat diet, the liver also has a neat trick called gluconeogenesis, a process that allows the body to produce glucose from ingested protein. Over the course of the day, the liver can produce enough glucose in this way to satisfy the brains' absolute needs for glucose.
What does all that mean? It means we can make enough glucose inside our bodies to fuel our brain and that it is not necessary to survive on carbs from plants. In fact, there's not such thing as an "essential" carbohydrate.
Premise 3: Eating meat is bad for the environment
The last vignette the documentary explores is the story of an ex-military Australian who's mission is to decrease poaching endangered species in Africa. It's all very emotionally driven and he said that he could not in good conscious continue to consume animal flesh while protecting the rhinoceroses.
The dialogue then turns to pointing out all the greenhouse gas emotions caused by global agriculture and the intense amount of plant products and water it takes to produce meat. While it's hard to deny that mono-culturing of crops to produce feed for feedlot animals has a host of environmental and ethical concerns, once again, the argument against meat makes a lot of assumptions.
They categorize "meat" as the stuff found in fast food hamburger patties and if that were all meat was, I would be in total agreement that it should be eschewed in favor of plants. But that's simply not the case. The documentary takes aim at "big meat" and lumps all meat in that category. This is the straw man fallacy. They make good claims against factory farmed meat products and think that is enough of an argument to dissuade people away from all meat.
But not all meat is factory meat and not all meat is bad for the environment. There are in fact methods of producing our meat that can be carbon neutral and even carbon sequestering, while honoring the immediate environment. One prominent example can be found in Polyface Farm in Virginia. This farm and its methods have been well documented in Michael Pollen's The Omnivore's Dilemma and in another documentary called Food, Inc. The farming methods used there produce 100% grass-fed beef on land that takes the entire ecosystem into account. It produces a sustainable farming method that, acre-for-acre, can even match the production of factory farms while being kind to the animals. Trouble is, these farms aren't supported by Government subsidies since they don't rely nearly as heavily on the corn industry. But I digress...
To simply state that meat eating is bad for the environment is really just silly. Humans have been contributing to the carbon cycle via meat eating for as long as we've been around without adverse consequences to the environment. It's just the modern, factory approach that's had a negative impact, but that doesn't have to be the only way we get our meat.
Overall, I thought at the very least, The Game Changers was a good film to help challenge the notion that Conventional, meat-based diets don't have to be the best diets for athletes and the modern human. I appreciated that they offered an alternative and I would absolutely join in their fight against factory farmed meat for the betterment of humanity. Where the film falls short is taking for granted the categories of "plants" and "meat" and makes too many assumptions about one versus the other. This dualistic thinking has marred much of the debate on what the modern human ought or ought not to consume. But, if it makes you think critically and think twice before your next fast food burger, then that's a win in my opinion.