Joe Rogan Experience #1393 - James Wilks & Chris Kresser - The Game Changers Debate

Episode Summary

Main Topics

This episode features a direct and intense debate between James Wilks, producer of "The Game Changers" documentary, and Chris Kresser, a functional medicine practitioner, regarding Kresser's critiques of the film. The discussion primarily revolves around the scientific evidence supporting plant-based versus omnivorous diets, dissecting claims related to gladiator diets, the influence of industry funding on nutritional science, the health implications of dairy and red meat, the truth about Vitamin B12 sources and deficiency, and the complexities of protein quantity and quality from plant versus animal sources, especially for athletes.

Key Discussion Points

• Gladiator Diet & Historical Accuracy: James Wilks clarified that "The Game Changers" stated ancient Roman gladiators were "predominantly vegetarian" and ate "mostly plants," not exclusively vegan, based on archaeological and anthropological data from the only known gladiator burial site in Ephesus. He argued Chris Kresser misrepresented this as a vegan claim, while Kresser maintained the film's portrayal was biased towards a plant-based narrative.
• Industry Influence on Research & Evidence Evaluation: A significant portion of the debate focused on how nutritional studies are funded and interpreted. Wilks asserted that industry-funded studies are 4 to 8 times more likely to show conclusions favorable to their sponsors, drawing parallels to the tobacco industry's playbook. He argued Kresser, by citing certain meta-analyses, was unknowingly or knowingly promoting research potentially swayed by meat and dairy industry funding.
• Dairy Consumption and Cancer Risk: Wilks challenged Chris Kresser's previous claim that 84% of meta-analyses showed no or inverse association between dairy and cancer. Wilks presented the actual study text, showing Kresser combined "no evidence" (71%) with "decreased risk" (13%) categories, while also noting 16% showed increased risk. Wilks also highlighted that the highest correlation found in Kresser's cited meta-analysis was a 50/50 split for dairy and prostate cancer, which Wilks argued isn't compelling evidence for causation, despite experts like Walter Willett suggesting a link.
• Vitamin B12 Sources and Supplementation: Wilks definitively refuted Kresser's previous dismissal of the film's B12 claims. He presented evidence (feed documents, supplier websites) showing common B12 supplementation in farm animals like chickens and cattle. Wilks also cited research indicating historical human B12 intake from unwashed plants and natural water, now reduced by modern sanitation. He further highlighted Kresser's own e-book, which cited the Framingham Offspring Study showing 40% of people (including meat-eaters) have low B12, directly contradicting Kresser's prior skepticism of a similar claim. Wilks concluded that B12 supplementation is the safest, surest, and most affordable way for everyone, globally.
• Protein Quantity and Quality for Athletes: Wilks systematically debunked Kresser's claims about the difficulty of obtaining sufficient protein from plants. He demonstrated that a peanut butter sandwich with two slices of bread provides 18 grams of protein, comparable to 3 ounces of lean beef, without excessive calories, countering Kresser's "five tablespoons of peanut butter" argument. Wilks also presented scientific consensus on athlete protein requirements (1.2-2.0 g/kg/day, with diminishing returns above 1.6 g/kg/day), arguing plant-based diets can easily meet these. He criticized the DIAAS protein quality score as being designed for preventing malnutrition in developing countries, not optimizing Western athletic performance, and cited recent Stanford research showing only a few percent difference in digestibility between plant and animal proteins.

Notable Moments

• Kresser's B12 E-book "Gotcha": James Wilks reveals that Chris Kresser's own e-book on B12 opened with a statistic (40% B12 deficiency in omnivores) that Kresser had previously dismissed as unreferenced or contradictory when made in "The Game Changers" film, leading to a significant "gotcha" moment.
• Forest Plot Interpretation Challenge: Wilks directly questioned Kresser's ability to read a "forest plot," a statistical chart used in meta-analyses, which Kresser admitted he could not. Wilks used this admission to challenge Kresser's authority in interpreting complex scientific data, especially regarding heme iron's effects.
• "Meat Causes Inflammation" Debate with Kangaroo vs. Wagyu Beef: Wilks presented a study comparing inflammatory markers (CRP, TNF-alpha, IL-6) after consuming kangaroo meat versus Wagyu beef, showing roughly half the inflammation from kangaroo. He used this to suggest that not all meat is equal and that even "healthy" meat (like Wagyu) can cause inflammation, though Kresser countered with studies showing plant foods can mitigate these effects.

Key Takeaways

The episode highlights the intense scrutiny and differing interpretations applied to nutrition science, particularly when challenging established dietary norms. Listeners gain insight into the specific scientific arguments both for and against common criticisms of plant-based diets, such as those regarding B12, protein, and the alleged inflammatory nature of meat and dairy. Wilks' detailed rebuttals, often citing Kresser's own words or studies, suggest that "The Game Changers" may have been unfairly characterized and that a well-planned plant-based diet is a viable and robust option for health and athletic performance.