What Happens to Your Body on the Carnivore Diet, According to a New Study

Scroll through social media long enough and you might stumble upon a diet that has become incredibly popular among certain crowds—it’s called the carnivore diet. With millions of posts under hashtags like #carnivore, this diet has captured significant attention. As you might have guessed, this diet centers on an all-animal-product approach, eliminating plant-based foods entirely.

The diet has been praised by its followers for delivering a wide range of health benefits. But what does the scientific evidence show? A recent review published in Nutrients set out to systematically explore the health effects and nutritional completeness of this popular diet.

How Was the Study Conducted?

To get a comprehensive overview of what we know about the carnivore diet, researchers undertook a scoping review, which is a methodology designed to collect and map out all available scientific literature on a topic, especially when the research is still emerging.

The researchers also performed a narrative literature search by manually combing through references and related articles to identify studies that might not be listed or easily indexed in the main databases.

Inclusion criteria were designed to cast a wide net but remain focused: only human studies that featured the carnivore diet, defined as primarily animal-based foods, with exceptions like herbs, coffee or alcohol, were considered. On the flip side, studies including diets with more than 10% of energy from plant foods, as well as animal and laboratory studies, unpublished data, preprints, conference abstracts, reviews and book chapters, were excluded.

After this thorough selection process, the final review included nine studies published between 2021 and 2025. These comprised a mix of methodologies: five case studies (including series and models), two social media surveys, one exploratory study and one comparative modeling study. This relatively small number highlights how little formal research has been conducted on the carnivore diet so far and sets the stage for interpreting the findings with appropriate caution.

What Did the Study Find?

The review painted a varied and nuanced picture of the carnivore diet by synthesizing evidence from different types of research, and there was considerable variability in how the carnivore diet was defined and practiced across the included studies.

In terms of health outcomes, the most widely reported motivation for trying the carnivore diet was to achieve better health, and many adherents said they noticed improvements. Surveys involving more than 2,000 participants highlighted frequent self-reported benefits, such as general health boosts, improved satiety, better sleep, mental sharpness and physical performance. Assessments of bloodwork in some studies aligned with these self-reports, showing improvements in inflammation markers like C-reactive protein (CRP) and liver function tests (such as lower gamma-glutamyltransferase, or GGT).

Yet, alongside these benefits, the study found serious reasons for caution. Multiple analyses of carnivore meal plans pointed out consistent shortfalls in key nutrients. Calcium, magnesium, vitamin C, thiamine (vitamin B1), potassium, folate and dietary fiber were all identified as either “insufficient” or, in some cases, “severely lacking.”

For instance, average calcium intake was often less than 800 milligrams per day (with the recommended amount being 1,000 milligrams for adults), and fiber intake was consistently under 1 gram per day, which is far below the 25 to 30 grams recommended for gut and heart health. There were also concerns for vitamins E and D, iodine, manganese and iron (especially for women). In some meal plan models, vitamin A reached levels far above recommendations due to high liver consumption, raising the risk of toxicity.

Laboratory results pointed to further risks. Many carnivore diet followers exhibited increases in LDL (“bad”) cholesterol and total cholesterol, sometimes to levels known to increase the risk of cardiovascular disease. In a study of 24 participants, the proportion with out-of-range lipid values only decreased slightly (from 24.4% before starting carnivore diet to 18.3% while following the diet), but the actual levels of total cholesterol and LDL were higher overall. Some participants with preexisting metabolic conditions did see improvements in hemoglobin A1c and triglycerides, but those who started healthy experienced rises in these markers.

Limitations of the Research

It’s crucial to understand the limitations of the current evidence. The nine studies analyzed were small, and none were long-term. This makes it impossible to know the effects of following a carnivore diet for years or decades.

Furthermore, there isn’t one single carnivore diet. The studies showed significant variation in what people ate. Some followed a strict diet of only red meat, salt and water, while others included eggs, dairy, fish and even small amounts of honey. This variability makes it difficult to draw firm conclusions that apply to everyone. The evidence is also largely based on self-reported data from surveys and individual case studies, which are not as reliable as controlled clinical trials.

How Does This Apply to Real Life?

The findings from this review have important real-world implications. While the diet’s simplicity and the reported short-term benefits are appealing, the potential for long-term health risks is considerable. Relying solely on animal products makes it very difficult to get all the nutrients your body needs without careful (and often expensive) supplementation. The lack of fiber, for instance, is a major concern for gut health and preventing cardiometabolic diseases.

We at EatingWell recommend a balanced diet that includes plenty of plant-based protein, fiber-packed whole grains and nutritious fruits and veggies. That’s why something like the Mediterranean diet can be such a great choice if you’re looking to change your eating habits.

Our Expert Take

This review published in Nutrients took a comprehensive look at the available research on the carnivore diet by gathering evidence from a range of recent case studies, surveys and dietary analyses. The results paint a complicated picture: while some people report health improvements such as reduced symptoms from chronic conditions or weight loss, others face real risks, particularly when it comes to nutrient deficiencies, increased “bad” cholesterol and inadequate fiber intake. The best evidence still supports a balanced diet that includes a wide variety of nutrient-dense foods, such as fruits, vegetables, whole grains and lean proteins.