The carnivore diet doesn’t have a single invention date. Its roots stretch back centuries to indigenous meat-based eating patterns, but the modern movement took shape between roughly 2006 and 2018, when online communities and a handful of vocal advocates turned all-meat eating from a medical curiosity into a named dietary trend. The idea that humans can thrive on animal foods alone, though, was first tested under clinical conditions nearly a hundred years ago.
Indigenous Diets That Inspired the Concept
Long before anyone called it “carnivore,” entire populations ate diets dominated by animal foods. The Inuit of the Arctic subsisted largely on seal, fish, and caribou. The Maasai of East Africa built their traditional diet around cattle blood, milk, and meat. These groups are still cited by carnivore diet proponents today, usually because of their historically low rates of heart disease.
The Maasai case is particularly interesting, and frequently misrepresented. Studies from the 1960s and 1970s found that among 227 Maasai individuals over age 15, average total cholesterol was just 135 mg/dL, with only seven people exceeding 200 mg/dL. Among 388 men examined, only a handful had elevated blood pressure. Those numbers sound like a vindication of high-fat eating, but the full picture is more complicated. The Maasai have genetic adaptations that allow them to absorb cholesterol at more than twice the rate of white Americans while simultaneously suppressing their own cholesterol production by 50%. They also burned an average of 2,565 calories per day above their baseline metabolic needs through constant physical activity, had a mean BMI of just 19.4, and ate no added salt. A 2025 review in Cureus concluded that these biological and lifestyle factors make the Maasai experience essentially inapplicable to modern sedentary populations adopting a carnivore diet.
The 1928 Bellevue Hospital Experiment
The first formal scientific test of an all-meat diet happened in New York City. In 1928, Arctic explorer Vilhjalmur Stefansson and his colleague Karsten Andersen checked into Bellevue Hospital to eat nothing but meat for an entire year under strict medical observation. Stefansson had already spent years living among the Inuit and eating their traditional diet, but skeptics dismissed his claims. The experiment was designed to settle the debate.
A committee of scientists led by Dr. Raymond Pearl of Johns Hopkins University oversaw the trial. The results, published in The Journal of the American Medical Association in 1929, surprised the medical establishment. Neither man showed signs of nutritional deficiency. Stefansson lost about 5.5 pounds, which he considered excess weight. Both men reported sleeping well, maintaining their mental sharpness, and actually appearing healthier by the end. Andersen even fought off a bout of pneumonia during the study, and his hair stopped falling out. The researchers noted “the apparent absence of monotony,” reporting that neither man craved non-meat foods. Most of the meat was boiled or stewed cold-storage beef, served rare on the inside.
This experiment became the foundational reference point for every all-meat eating advocate who followed. It proved, at minimum, that two adults could eat exclusively meat for a year without obvious harm.
The Zero-Carb Community: 2006 to 2017
For decades after the Bellevue experiment, all-meat eating remained a fringe curiosity. That changed in the mid-2000s with the rise of online forums. Communities built around “zero carb” eating began forming, with members sharing their experiences eating only animal products. These groups existed mostly on message boards and later on Facebook and Reddit, where participants tracked their health changes and debated the finer points of eating nothing but meat and animal fat.
Research into these communities found that members frequently encountered social conflict. A 2021 survey of zero-carb dieters documented tensions within families and friendships, as well as difficult interactions with healthcare professionals who viewed the diet as dangerous. The community remained small and self-reinforcing, largely invisible to the mainstream.
Shawn Baker and the “Carnivore Diet” Brand
The transition from underground zero-carb community to mainstream diet trend happened largely through one person: Shawn Baker, an orthopedic surgeon and competitive athlete. Baker became the diet’s most prominent advocate around 2017, promoting it aggressively on social media and eventually publishing “The Carnivore Diet” as a book. He’s widely credited with popularizing the term “carnivore diet” itself, giving the movement a catchier name than “zero carb” and a visible public face.
Baker’s message was simple: eat meat, drink water, and nothing else. His athletic physique and willingness to debate critics online gave the diet credibility among fitness-minded audiences. His social media presence grew rapidly, and the diet began attracting attention from people well beyond the original zero-carb forums.
Celebrity Endorsements and Viral Growth
The carnivore diet broke into true mainstream awareness through high-profile testimonials, most notably from psychologist Jordan Peterson and his daughter Mikhaila. Both described dramatic health improvements after switching to an all-meat diet, and their appearances on popular podcasts carried the message to millions of listeners. The “Maintenance Phase” podcast later devoted a two-part series to tracing how the diet gained traction, noting the unlikely chain of influence that connected a 1950s bodybuilder, a Grateful Dead roadie, and Peterson into a single dietary movement.
These celebrity stories accelerated interest far beyond what Baker alone could generate. Search interest for the term “carnivore diet” spiked repeatedly between 2018 and 2022, each surge tied to a new public figure sharing their experience.
Medical and Research Responses
As the diet gained popularity, health organizations pushed back. In 2021, the American Heart Association released dietary guidance that ranked very low-carbohydrate diets, including ketogenic and paleo-style eating, as the worst options for heart and metabolic health. The AHA emphasized plant foods over animal foods for cardiovascular disease prevention. The carnivore diet, which is more restrictive than any of the diets the AHA evaluated, wasn’t even included in their ranking, likely because it was considered too extreme to warrant formal analysis alongside established diets.
Meanwhile, a clinic in Hungary called Paleomedicina began quietly accumulating clinical data on a related approach. Starting in 2009, they treated patients with a “paleolithic ketogenic diet” that centered on animal foods with high fat-to-protein ratios. By 2013, they had worked with roughly 2,000 patients and reported improvements in blood pressure, blood sugar control, weight, thyroid function, migraines, and acid reflux. They also documented cases where the approach fell short, particularly with autoimmune conditions like Crohn’s disease and rheumatoid arthritis, as well as certain cancers. This remains some of the only clinical data collected on a carnivore-adjacent diet, though it comes from a single clinic rather than controlled trials.
Why There’s No Single “Creation” Date
The carnivore diet wasn’t invented in the way that, say, the Atkins diet was packaged and launched in 1972. It evolved through overlapping waves: indigenous eating patterns observed for centuries, a clinical experiment in 1928, online communities forming around 2006, a named movement emerging around 2017, and viral celebrity adoption from 2018 onward. If you need a single year, 2017 to 2018 is when “the carnivore diet” became a recognizable concept with that specific name. But the practice of eating only animal foods is as old as human survival in Arctic climates, and the scientific question of whether it’s safe has been formally studied since the late 1920s.