The Game Changers: Do Its Claims Hold Up?

Published: 4 October 2026

The Game Changers is one of the best-known films about plant-based eating and sport. Netflix describes it as the journey of a UFC fighter who meets visionary scientists and elite athletes in search of the best diet for human performance and health. The fighter is James Wilks, the director is Louie Psihoyos, and the executive producers include James Cameron and Arnold Schwarzenegger. Variety reviewed it in March 2018, after festival screenings at Sundance and Berlin. Here are six of its claims, checked one at a time against published studies.

Claim 1: Vegan athletes can compete at the top level

Verdict: supported.

Even the film’s sharpest critics agree. Joe Schwarcz of McGill University’s Office for Science and Society, who called the film “basically a two-hour promo for a vegan lifestyle”, wrote that “there is nothing about a vegan diet that would preclude this” and that it is “certainly possible with proper attention to food intake to meet the body’s protein needs.”

Claim 2: A plant-based diet makes you perform better

Verdict: not supported by the evidence so far.

A 2016 systematic review found only eight studies that directly compared vegetarian and mixed diets on physical performance, seven of them randomised trials. It found “no distinguished differences”: a mostly vegetarian diet “did not improve nor hinder performance”. A 2018 review in Nutrients agreed that plant-based diets are unlikely to give an advantage, and do not put athletes at a disadvantage, in strength, anaerobic or aerobic exercise. One cross-sectional study found higher VO2 max in vegetarian than in omnivorous women, but not in men, and a snapshot like that cannot show cause. All three papers note how thin the research is.

The athletes on screen are real, but they are anecdotes. The sports nutrition scientist Asker Jeukendrup made this point about Patrik Baboumian’s reported 25 kg weight gain after going plant-based: such a story shows the gain is possible on a plant-based diet, but not that another diet would have done worse.

Claim 3: Plant protein builds muscle as well as animal protein

Verdict: supported, if protein intake is high enough.

In a 2021 trial in Sports Medicine, 19 untrained young men who were habitual vegans and 19 omnivores did 12 weeks of resistance training, twice a week, with protein topped up to 1.6 g per kg of body weight a day: soy for the vegans, whey for the omnivores. Both groups gained 1.2 kg of leg lean mass, with no difference in muscle size or strength.

A 2023 study in the Journal of Nutrition pushed protein higher, to about 2 g per kg a day, over 10 weeks of heavy training. In one group all of it came from non-animal sources. Lean mass, thigh muscle volume and strength rose to a similar degree in both groups.

Both trials were small and short, and both used generous protein intakes with supplements. Our guide to protein quality explains why total protein and the mix of sources matter for vegans.

Claim 4: Roman gladiators were vegetarian

Verdict: overstated.

The film’s gladiator segment rests on bone-chemistry evidence, chiefly a 2014 study of a gladiator cemetery at Ephesus, in today’s Turkey, dated to the 2nd and 3rd centuries AD. The researchers analysed the bones of 53 people, 22 of them gladiators. Roman texts called gladiators hordearii, “barley eaters”, and the bones confirm that wheat and barley were the staple food. Two findings support the film’s picture: the gladiators’ strontium-to-calcium ratios were significantly higher than those of other Ephesians, possibly from a plant-ash drink, and the generally low nitrogen values across the city point to frequent legume eating.

But nitrogen values, which reflect meat and dairy intake, did not differ between gladiators and ordinary Ephesians. The two highest values in the sample belonged to gladiators; for those two, the authors inferred “a regular consumption of animal proteins”. They described the people buried in the gladiator cemetery as “a very heterogeneous group who consumed different kind of foods”. Jeukendrup’s summary is fair: “they were NOT vegetarians or vegans. They just ate a lot of vegetables.”

Claim 5: One meat meal thickens your blood and narrows your arteries

Verdict: the demo proves nothing; the real effect is about fat, not meat.

The film’s website says the experiment on three NFL players showed that “a single animal-based meal can quickly thicken our blood”. On screen, their plasma looked cloudier after a meat meal than after a plant meal. Schwarcz called the comparison “meaningless”: the sample is far too small, and he dismissed any link between cloudy plasma and artery function.

There is research on the underlying effect, though, and it points to fat. In a 1997 study led by the cardiologist Robert Vogel, ten healthy volunteers ate two meals of the same 900 calories, one with 50 g of fat and one with none. After the high-fat meal, blood triglycerides rose from 94 to 147 mg/dl, and flow-mediated dilation, a measure of artery function, fell from 21% to 11% at two hours. The low-fat meal changed neither. The effect was temporary, and the comparison was high-fat against no-fat, not meat against plants. Our article on plant-based diets and heart health covers the long-term evidence.

Claim 6: Meat affects erections

Verdict: the demo proves nothing; the association is plausible.

Three men wore a device that recorded night-time erections after a meat meal and after a plant meal. Schwarcz called three men “a statistically meaningless sample size” and noted that nothing was known about their medical history or lifestyle.

A 2025 meta-analysis pooling 14 studies of several diets, with 27,389 participants, found plant-based diets linked to lower odds of erectile dysfunction (odds ratio 0.71). Studies like these track long-term eating habits; they cannot tell us what a single meal does overnight.

What else to watch for

McGill’s review flags more claims that do not hold up, from iceberg lettuce supposedly beating salmon and eggs for antioxidants to a peanut butter sandwich supposedly matching a three-ounce (about 85 g) steak for protein. Crediting the Tennessee Titans’ playoff run to 16 players going vegan is, it says, “a big stretch”.

Whatever the film covers, vegan athletes still need to plan for a few nutrients, starting with vitamin B12.

Should you watch it?

Watch it as a well-made, motivating film with real athletes in it, not as evidence. Even Schwarcz granted that it “does make some solid points about the environmental unfriendliness of animal agriculture” and that if it moves viewers towards a more plant-based diet, “it will have done some good”. Its strongest true message is that a well-planned plant-based diet does not hold athletes back. Its weakest is the promise that it will push them ahead.

Where to watch

Netflix Türkiye: the film has a title page, but when we checked on 2 October 2026 it said the film was not currently available in Turkey.
Other platforms: the film’s official website lists digital platforms such as iTunes, Google Play and Vimeo, but the page dates from 2019 and we could not confirm current availability in Turkey.

Sources

Netflix Türkiye. The Game Changers title page, checked 2 October 2026.
The Game Changers. Where to Watch and The Plant-Based Advantage, official film website.
Lodge G. Film Review: The Game Changers. Variety, 8 March 2018.
Schwarcz J. Will “The Game Changers” change your game?. McGill Office for Science and Society.
Jeukendrup A. Is Game Changers game changing or is it sensationalism?. mysportscience, 6 November 2019 (archived copy).
Craddock JC, Probst YC, Peoples GE. Vegetarian and omnivorous nutrition – comparing physical performance. Int J Sport Nutr Exerc Metab. 2016;26(3):212–220.
Lynch H, Johnston C, Wharton C. Plant-based diets: considerations for environmental impact, protein quality, and exercise performance. Nutrients. 2018;10(12):1841.
Lynch HM, Wharton CM, Johnston CS. Cardiorespiratory fitness and peak torque differences between vegetarian and omnivore endurance athletes: a cross-sectional study. Nutrients. 2016;8(11):726.
Hevia-Larraín V, Gualano B, Longobardi I, et al. High-protein plant-based diet versus a protein-matched omnivorous diet to support resistance training adaptations. Sports Med. 2021;51(6):1317–1330.
Monteyne AJ, Coelho MOC, Murton AJ, et al. Vegan and omnivorous high protein diets support comparable daily myofibrillar protein synthesis rates and skeletal muscle hypertrophy in young adults. J Nutr. 2023;153(6):1680–1695.
Lösch S, Moghaddam N, Grossschmidt K, et al. Stable isotope and trace element studies on gladiators and contemporary Romans from Ephesus (Turkey, 2nd and 3rd Ct. AD). PLoS One. 2014;9(10):e110489.
Vogel RA, Corretti MC, Plotnick GD. Effect of a single high-fat meal on endothelial function in healthy subjects. Am J Cardiol. 1997;79(3):350–354.
Yang B, Wei C, Zhang YC, et al. Association between improved erectile function and dietary patterns: a systematic review and meta-analysis. Asian J Androl. 2025;27(2):239–244.

Editor: Anıl Güler, Pharmacist
Last reviewed: 2 October 2026