Dietary Diversity or Carnivore: Which Fuels Better Health, Longevity, and Performance? Dr. Shawn Baker & Joel Greene Debate

Ben Greenfield

Sep 27, 2025

Episode description

In this episode we dive into a hotly debated topic: should you eat meat or not? Ben is joined by two powerhouse guests with decades of experience in nutrition and health—Dr. Shawn Baker, best-selling author of The Carnivore Diet and leading carnivore advocate, and Joel Greene, creator of The Immunity Code and champion of dietary diversity.

In this spirited debate, Dr. Baker highlights the benefits of a strict carnivore approach—meat, eggs, some dairy, and minimal plant foods—not only for himself but also for patients managing chronic health issues. He explains why animal-based nutrition can be so effective, breaks down the science of ketosis and gut health, and responds to concerns about long-term effects of fiber-free diets.

Meanwhile, Joel Greene makes the case for dietary variety, drawing from evolutionary biology, clinical research, and personal experience. He explores the synergies of combining animal and plant foods, the role of fiber in gut and immune health, and the ancestral rhythms of scarcity and feasting. Joel argues that even small amounts of diverse foods can offset downsides of strict elimination diets.

Dr. Baker is a physician, athlete, and author known for his straightforward, meat-focused approach to nutrition and his background in strength sports. Joel is the creator of Veep Nutrition, a program targeting gut communities to improve health, used by major employers and featured on the Dr. Phil Show. Author of The Immunity Code, Joel has devoted 50 years to health and anti-aging, pioneering practices like MCTs in the ’80s, keto in the ’90s, and AMPK activation by 2009. At 55, he remains a 100% natural athlete.

Full show notes: bengreenfieldlife.com/diversityorcarnivore

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Mindsip insights from this episode:

Measure two methylbutyl carnitine to assess metabolic distress on keto

You can measure a specific marker called 'two methylbutyl carnitine' to check for metabolic distress that may arise from prolonged keto or carnivore diets.

#keto

#testing

Beware long-term ketosis risks from high-fat diets

A potential long-term liability of high-fat diets is that the body's ability to burn fat (beta-oxidation) can outpace its ability to use the energy (TCA cycle), leading to an accumulation of stressful intermediates called acylcarnitines.

#keto

#metabolism

Utilize carnivore diet as short-term therapeutic tool

The carnivore diet is best viewed as a short-term therapeutic tool for three to six months to address issues like autoimmune conditions or gut problems, not necessarily a lifelong diet for everyone.

#carnivore

#nutrition

Experience enhanced focus and muscle pump with Outlier pre-workout

The pre-workout 'Outlier' uses paraxanthine, a cousin of caffeine, along with Cognizin for focus and 3T (betaine nitrate) for a significant muscle pump.

#muscle

#supplement

Incorporate grains to enhance muscle synthesis in high-protein diets

Adding about 50 grams of grains per thousand calories to a high-protein diet has been shown to improve muscle synthesis rates, demonstrating a synergy between food groups.

#muscle

#nutrition

Live normally without a colon after colectomy

People who undergo a colectomy (colon removal) can live a normal lifespan, which questions the absolute essentiality of the colon's microbiome for long-term health.

#longevity

#microbiome

Distinguish protein putrefaction from fiber fermentation for gut health

The bacterial breakdown of protein in the colon is called putrefaction and produces ammonia, whereas fiber fermentation produces beneficial antioxidants and short-chain fatty acids.

#digestion

#microbiome

Add fiber to prevent cancer from alkaline colon

Contrary to popular belief, an alkaline colon—which can be caused by high-protein, no-fiber diets—is a major cancer promoter, and this is easily solved by adding a small amount of fiber.

#cancer

#fiber

Question cholesterol reliability with dramatic fluctuations

A personal experiment showed that total cholesterol can fluctuate dramatically, rising from 154 to 345 in just 18 hours after fasting and exercise, questioning the reliability of a single blood test.