Greg talks about his journey on the carnivore diet.
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Title: “I Didn’t Eat for 39 Hours… Then Ran 62 Miles (Fasted) — Carnivore Ultra Runner Interview”
Summary (from the video only; no sponsors, no CTAs):
• Background
Greg describes discovering the carnivore diet via a relative (his uncle).
Initial skepticism (“you need fiber/fruit/veg”) shifts after trying it himself.
• Pre-carnivore health/issues
Long-standing eczema/skin problems treated repeatedly with steroid creams and pills.
A severe rash two years prior led to more steroids; doctors framed it as “this is who you are.”
• Switching to carnivore
Adopted a meat- and egg-based diet after conventional approaches failed.
Within ~2 weeks he noticed significant improvement in skin/eczema.
Reports steadier energy, reduced food preoccupation, simpler meals, and less stress about recipes.
• Training/running context
Took up running ~1–1.5 years prior; later got into ultrarunning.
Began experimenting with fasted training runs (dinner the night before, then run without breakfast).
• The fasted 100K (≈62 miles)
Entered a 100-kilometer ultramarathon with a plan to remain fasted.
Did not eat for 24 hours before the start, ate only after finishing.
Total time without food ≈39 hours (24 hours pre-race + ~15 hours of racing).
During the race he consumed only water and electrolytes (salt-stick type: sodium, potassium, magnesium).
Took roughly one electrolyte capsule per hour to prevent cramps/fatigue.
Reports no GI issues, no energy crashes, and no “hitting the wall.”
Observed other athletes consuming large amounts of carbohydrates (he mentions ~80–100 g/hour as a common target among ultrarunners) and some experiencing bonks/crashes.
• Perceived effects/observations
Describes stable, even energy throughout most of the race; acknowledges normal late-race fatigue but no bonk.
Says he has “never hit the wall” since being on carnivore.
Notes that conventional endurance advice (high-carb fueling) conflicted with his experience.
• Adaptation period & practical notes
Warns athletes to expect an adaptation period (possibly 1–2 months of worse performance) when switching diets.
Emphasizes electrolytes (sodium/potassium/magnesium) and hydration on carnivore/fasted runs.
Typical pre-run approach outside of races: eat the evening meal, then run fasted the next morning.
• Social reaction & debate
Fellow runners were surprised he attempted and completed a 100K entirely fasted.
Mentions critics of carnivore and says he’s open to being a “guinea pig” for testing/measurement in the future.
Referenced papers (as mentioned in the video):
• None explicitly cited; no DOI-identifiable papers referenced by title or author in the conversation.