The Game, Unchanged (Short Version)

Dr. Mel Davis, PhD
Read the full article with over 200 scientific references here!


There is an enormous scientific consensus that eating a plant predominant diet has a multitude of potential health benefits. Upon closer inspection of this evidence, however, these benefits mainly appear to result from the addition of whole plant foods, not, as Game Changers claims, from the elimination of animal products (with the exception of evidence in support of reducing red meat consumption and especially minimizing processed meat consumption). 

The overall data suggest that a health and fitness-promoting diet need not be vegan, unless you want it to be. At the end of the day, both vegans and omnivores alike may need to supplement their diets with some nutrients while minimizing other foods for optimal health and fitness.

The health and fitness “game” continues to boil down to maintaining a healthy weight, exercising, and eating a diet rich in fruits, vegetables, sufficient protein, healthy fats, and unprocessed whole foods. Omnivore or vegan, the data continue to tell us that athletic performance is fueled by informed diet choices, relentless hard work, and good genetics. 

READ MORE on any points below, or browse (over 200!) scientific works cited

Section-by-Section Responses to Claims Made In Game Changers:

Unless you aspire to be overweight and fight wild animals, the Gladiator diet - much of which is unconfirmed, but likely having consisted of primarily grain, possibly with some meat and/or seafood - is probably not the way to go. 

Yes, it’s totally possible to get all of the essential amino acids from plant protein. Achieving this just takes a little more care and consideration on a vegan diet, due to differing amino acid ratios and absorption rates.

There is no evidence that plant protein is better for muscle mass retention or gain. There is evidence that animal protein is superior, but a growing body of research suggests that protein source - plant or animal - is likely irrelevant for muscle protein synthesis, given adequate consumption and attention to amino acid ratios. Total carbohydrate and total energy intake are the main determinants of endurance performances in healthy athletes. 

You can eat blueberries, drink green tea and eat chicken! High fat meals of all types, vegan or animal-based, can result in lipemia (cloudy blood) and acutely impair endothelial function. Game Changers, accurately references the large body of evidence for plants having a positive impact on endothelial function. However, none of the 19 papers cited in the documentary compare vegan and omnivorous diets, bringing us back to the fact that showing how plants can improve our health, does not show how - or whether - meat hurts it. 

Dietary nitrate (contained in beetroot juice) might be a worthwhile supplement for athletes, but the details, dosages, and effects are still being worked out. No studies of relative effects of beetroot juice or dietary nitrate on vegans versus omnivores were cited in the documentary.

Heme iron is a well-absorbed version of a mineral essential for bodily function found only in meat, over-consumption of which may carry cardiovascular risk and risk of certain cancers. Conversely, vegans run the risk of under-consuming iron, which can lead to anemia and is associated with cardiovascular dysfunction and risk of certain cancers. In both cases, a little diet tuning should mitigate respective risks: meat eaters can minimize red meat consumption and vary their iron sources, while vegans can increase iron intake with supplementation.

Microbiome and TMAO changes in response to foods varies from person to person, and we do not presently know enough about either TMAO or its relation to the microbiome to make any dietary recommendations. 

On average, plants do have more antioxidants than animal products, but you can eat both and still get the benefits of plants. 

Vegan and vegetarian interventions consistently have health benefits. But, keeping the meat and adding fruits, vegetables, fiber, and plenty of whole foods seems to have the same benefits. 

The bulk of the literature suggests that cardiovascular risk is not associated with plant versus animal protein source.


  • Prostate Cancer: The strongest association is adult body fatness. Individual dietary factors are not conclusively predictive of prostate cancer risk, while eating lots of whole foods and n-3 polyunsaturated fatty acids (whose primary source is fish), and limiting alcohol intake are associated with decreased risk.
  • Breast Cancer: The strongest associations with this cancer is alcohol consumption, adult weight gain, and adult body fatness, while physical activity and lactation are associated with decreased risk. Some data also link intake of lowfat dairy with a decreased risk, but others find no association.
  • Colorectal Cancer: The strongest associations with risk include salted fish consumption, alcohol consumption, and adult body fatness. Smoked foods of any kind and meats cooked under high heat also seem to be risk factors. Lots of fruits, vegetables, and fiber appear to be associated with reduced risk, and some data suggest the same for milk products, fish, and poultry consumption. 

The healthiness of (or lack thereof) of participants’ diets prior to going vegan was not assessed. Research suggests that switching to a healthy, lowfat, high fiber, veggie and fruit-centric diet with lean animal protein would have had the same effect. 

Veganism does not appear to alter free testosterone. Further, it seems that diet might not directly affect sex hormones (though weight and body fat might). There is no evidence that erections are related to plant versus animal protein consumption.

Soy consumption appears to have both benefits (ex: reduced risks of certain cancers) and risks (ex: increased risks of certain cancers). 

Relationships between meal content and stress hormones are complex, but, contrary to Game Changers’ insinuations, carbohydrates seem to be more related to cortisol changes than protein.

Read the full article with over 200 scientific references here!

RP Tools For Vegans

Vegan Diet Templates 
A modified version of our top-selling diet templates to fit the needs of vegan athletes and fitness enthusiasts.

RP Vegan 
50 RP diet-friendly and delicious protein recipes for a plant-based diet!

The RP Diet For Endurance 
This 50 page read has everything you need to know about fueling, hydrating and managing electrolytes for ultimate performance.


Back to blog