An Evidence-based Review of ‘The Game Changers’

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This fantastic guest post was written by Dietetic student Zachary Wenger. This review summarises some of the main issues related to this biased and scare-mongering film, and it’s great that it has been written by an evidence-based vegan like Zachary.

You can follow Zachary on Instagram @Planted

Whether it’s for environmental, ethical, or nutritional reasons, veganism is growing exponentially in popularity, and many professional athletes are now following this lifestyle.

We can look at Venus Williams, professional tennis player, to Kyrie Irving, professional basketball player, to Kendrick Farris, olympic weightlifter. All vegan and all at the top of their game.

The Game Changers release is drawing in a ton of debate. The film was produced by James Cameron and it promotes a vegan diet, which is the practice of reducing all forms of animal exploitation as much as reasonably possible.

This film has had very mixed reactions, some people love the pro-vegan messages while others feel that it is biased and full of anecdotes and poor research.

Some background on me before I give my thoughts on the film. I’m a college dietetics major, and intern here at Dietetically Speaking. I have been vegan for over 3 years now and am a huge advocate of the ethical principles of veganism. However, my stance on the ethics, will not and can not overshadow the current knowledge we have on nutrition.

Plant vs. Animal Protein

“I think one of the biggest misconceptions in sports nutrition, is that we have to have animal protein, to get big and strong and perform at a high level. That’s just clearly not true.”  – The Game Changers

That is correct. Animal protein isn’t in any way essential to the body. If you switch to plant protein, you will not spontaneously develop kwashiorkor.

A legitimate potential downside would be that on average, the amino acid profile of plants is less optimal than in animal products. EAA’s cannot be produced by the body, therefore they are essential to obtain through our diet. Contrary to popular belief, plants are indeed complete sources of protein, just like animal-based proteins (1). They differentiate by simply containing less of the essential amino acids. For example, plants are lower in the EAA lysine and leucine relative to animal-based proteins.

It is also true that on average, the further one restricts animal products, on a population level, the less protein one consumes (2). This could be the case simply due to consuming fewer kilocalories, which is common after shifting to a vegan diet. Another potential explanation may just be absorbing information from certain vegan medical doctors, who claim that protein decreases longevity (based solely on animal models, bleh).

Nonetheless, this could be problematic for vegans with higher protein requirements, like athletes (3). The good news is that there are suitable workarounds. Going vegan doesn’t mean that you’re out of luck. Plants that are rich in protein include legumes, tofu, seitan, tempeh, plant-based protein powder, mock meats, and more!

Bottom line, it is true that we do not need animal-based protein to build muscle. We can properly build muscle on plants, and get enough protein. Though, I would be hesitant to claim that plant protein are superior for athletic performance relative to animal protein. If essential amino acids are matched across both diets, we wouldn’t expect significant differences.

Plant vs. Animal Burrito Blood Lipid ‘Experiment’

This part of the movie had my blood boiling (pun intended). Cardiologist, Robert Vogel, conducted an experiment with 3 NFL players, where he gave them each a plant based burrito and a meat based burrito, then compared the blood drawn 2 hours after each meal.

As we can see from the image, the blood after consumption of the plant based meal is clear and transparent, while the meat based meal resulted in a cloudy effect. This made major headlines because according to the film, the cloudy serum we see with the meat based burrito, symbolizes endothelial dysfunction. 

This sounds scary, but how much of this is science and how much of this is fear-mongering? 

The cloudy effect seen in the blood, is called postprandial lipemia.

It is physiologically normal to see a rise in triglyceride rich lipoproteins in the blood post-consumption of dietary fat.

If we tested these athletes fasted, their serum would all look identical. Hence, why the film decided not to take fasted samples. It wouldn’t have fit their agenda. Using non-fasted triglycerides is inherently flawed due to meal-timing and fat content of the last meal. 

The film claimed they added avocado to the plant-based burrito, which should show cloudy serum as well. Why didn’t it? 

For one, we don’t know how much avocado was added, because this wasn’t a published study. Were the fat contents matched for both burritos? Was it due to the difference in polyphenols? We can’t look at the methodology, all we can do is take the film’s word for it, which is not how science works. Luckily, they cited a paper that apparently replicated the results they achieved (4).

The study looked at different foods in relation to the rise in postprandial triglycerides.

Olive oil, which is vegan, had the same postprandial rise in triglycerides as cheesecake and hamburger/fries!

Now, is this something to worry about? Should we all be eliminating olive oil due to this? Definitely not. Interestingly, when you pool together multiple papers on this topic into a meta-analysis, olive oil would actually improve endothelial function (5)! To take it a step further, when looking at actual risk for disease, cardiovascular disease (CVD) specifically, olive oil consumption has consistently been associated with a reduced risk for CVD (6).

Furthermore, the researchers even found that salmon had half the rise in triglycerides relative to olive oil. They also found that omega-3 fatty acids, vitamin C, and vitamin E improved endothelial function.

According to the research that The Game Changers linked, and our current knowledge on postprandial lipemia, this is not an issue with consuming plants vs animals. It is simply what we see when we draw blood from an individual that just consumed a fatty meal.

Vegan Diets and Health Outcomes:

Towards the end of the film,  they share success stories of individuals that have lowered their cholesterol, blood pressure, BMI, etc,from going vegan. Which brings up the question, do you need to go fully vegan to achieve these benefits?

A landmark paper that looked directly at this was the Adventist Health Study 2 (7). The study took a total of over 96,000 Seventh-day Adventist men and women and followed them for seven years. Seventh-day Adventists believe that the body is the temple and they eat plant predominant diets, though not all fully vegan. For example, there were over 5,000 vegans (only plants), 21,000 lacto-ovo vegetarians (dairy, eggs, and plants), 7,000 pescatarians (seafood and plants), 4000 semi vegetarians (consumed meat no more than 1x per week), and 35,000 nonvegetarians (omnivores, though still plant centric). 

While vegan men had a lower incidence of ischemic heart disease, total cardiovascular disease, total cancer, and a lower death rate from all causes relative to the other diet groups, the same couldn’t be said for the vegan women. They didn’t perform nearly as well as the vegan men and the explanation for that has been an ongoing academic question that has stumped many. 

Furthermore, when you pool together the men and women into their respected diet groups and not separated by gender, the lacto-ovo vegetarians had the lowest incidence of total cancer and the pescatarians had the lowest incidence of total cardiovascular disease, ischemic heart disease, and all cause mortality. 

Now, this isn’t to demonstrate that a vegan diet would increase risk for disease. Rather, that while a vegan diet is great, it’s not the only diet that can produce positive results. The Game Changers shares stories of individuals following a whole food plant based diet. This diet does not include oil, added sugar, or ultra processed foods, whereas a typical vegan diet may.

A whole food plant-based diet primarily works because it promotes a frequent intake of fruits, vegetables, legumes, and whole grains. It promotes the intake of fibre, which can lower cholesterol, increase satiety, lower blood pressure, lower risk of certain gut diseases, lower risk of heart disease, and more (8). Also, consuming only whole foods completely eliminates the consumption of ultra-processed hyper-palatable food, which could assist one in lowering kilocalories. Whole plants are typically lower in kilocalories, which can aid in creating a caloric deficit, and in result, assist in weight loss. Plants are also typically lower in saturated fat. Reductions in saturated fat can lower LDL cholesterol (9). However…..

— Do you *need* to go vegan to consume more fiber? No. 

— Do you *need* to go vegan to eat more fruits/vegetables? No. 

— Do you *need* to go vegan to go create a caloric deficit? No. 

— Do you *need* to go vegan to decrease saturated fat intake? No again. 

We can all make steps in the right direction, which doesn’t require going entirely vegan. Animal products aren’t essential to the diet, but are a great source of vitamins that are harder to obtain on a vegan diet, like Vitamin D and Vitamin B12.

Quality of Evidence:

The quality of evidence in this film was extremely poor. Multiple times, the film conducted experiments on 3 people and made firm conclusions off those experiments.

While these experiments are entertaining, they’re far from robust. In reality, they are glorified anecdotes. There was no control group, there was no randomization, there was no blinding, there were no statistical adjustments like we would expect to see in a well-powered randomized controlled trial. Well, I guess it’s hard to randomize participants when there are only 3 total people doing the experiment…

Glorifying experimentation on three individuals, rather than presenting converging lines of robust human outcome data on a respected topic, is just silly.


I understand that The Game Changers’ end goal is to get people to change dietary patterns and go vegan. I understand what they were attempting to do, I’m emotionally tied to the ethics of veganism. However, I still find it morally wrong to conflate animal ethics with actual robust science.

Using fear-mongering tactics on people who are uninformed, is simply not the right way to grow veganism.

This will just continue the influx of stories from individuals ditching their vegan diet because they were misled, which in turn negatively impacts the vegan movement.

In terms of health, there are numerous benefits related to plant-based diets. but plant-based doesn’t mean plant-only!

We need to remember that veganism is an ethical position. There are solid ethical reasons to adopt a vegan diet if one so chooses to do so. We don’t need to stretch the science in order for it to fit our biases. Again, this hurts the movement long term. 

It is vital that we make informed choices about our diet, rather than fear-induced choices on the back of biased and sensational documentaries like The Game Changers.


  1. Gardner, Christopher D et al. “Maximizing the intersection of human health and the health of the environment with regard to the amount and type of protein produced and consumed in the United States.” Nutrition reviews vol. 77,4 (2019): 197-215. doi:10.1093/nutrit/nuy073
  2. Allès, Benjamin et al. “Comparison of Sociodemographic and Nutritional Characteristics between Self-Reported Vegetarians, Vegans, and Meat-Eaters from the NutriNet-Santé Study.” Nutrients vol. 9,9 1023. 15 Sep. 2017, doi:10.3390/nu9091023
  3. Jäger, Ralf et al. “International Society of Sports Nutrition Position Stand: protein and exercise.” Journal of the International Society of Sports Nutrition vol. 14 20. 20 Jun. 2017, doi:10.1186/s12970-017-0177-8
  4. Vogel R. A. (1999). Brachial artery ultrasound: a noninvasive tool in the assessment of triglyceride-rich lipoproteins. Clinical cardiology, 22(6 Suppl), II34–II39.
  5. Schwingshackl, Lukas et al. “Effects of Olive Oil on Markers of Inflammation and Endothelial Function-A Systematic Review and Meta-Analysis.” Nutrients vol. 7,9 7651-75. 11 Sep. 2015, doi:10.3390/nu7095356
  6. Guasch-Ferré, Marta et al. “Olive Oil Consumption and Cardiovascular Risk in U.S. Adults.” Journal of the American College of Cardiology vol. 75,15 (2020): 1729-1739. doi:10.1016/j.jacc.2020.02.036
  7. Orlich, Michael J et al. “Vegetarian dietary patterns and mortality in Adventist Health Study 2.” JAMA internal medicine vol. 173,13 (2013): 1230-8. doi:10.1001/jamainternmed.2013.6473
  8. Anderson, James W et al. “Health benefits of dietary fiber.” Nutrition reviews vol. 67,4 (2009): 188-205. doi:10.1111/j.1753-4887.2009.00189.x
  9. Hooper, Lee et al. “Reduction in saturated fat intake for cardiovascular disease.” The Cochrane database of systematic reviews vol. 5,5 CD011737. 19 May. 2020, doi:10.1002/14651858.CD011737.pub2


Maeve has been consulting on The Food Medic Educational Hub for 12 months now and has been a huge asset to the team. Her ability to translate some very nuanced topics in nutrition into easy-to-follow, informative articles and infographics is really admirable.

Dr Hazel Wallace

Founder of The Food Medic

Maeve is incredibly talented at sharing scientific information in an easy to understand way. The content she shares with us is always really interesting, clear, and of very high quality. She’s one of our favourite writers to work with!

Aisling Moran

Senior UX Writer at Thriva Health

Maeve has written extensively for NHD magazine over the last few years, producing a wealth of dietetic and nutritional articles. Always evidence based and factual, Maeve creates material that is relevant and very readable. She provides high quality work with a professional and friendly approach. Maeve is a beacon of high quality knowledge and work within the nutrition writing community; and someone NHD magazine is proud to work with.

Emma Coates

Editor of Network Health Digest

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