What Is the Lion Diet? Rules, Risks & Alternatives

Quick Answer: The Lion Diet is an extreme elimination diet that allows only ruminant meat (beef, lamb, bison), water, and salt. Created by lifestyle blogger Mikhaila Peterson, it's sometimes used short-term to identify food triggers—but it lacks clinical evidence and isn't endorsed by medical professionals. Experts warn that meat-only patterns can raise LDL cholesterol, eliminate essential fiber, and increase colorectal cancer risk with prolonged use. A safer approach is a structured elimination diet with guided reintroductions.

What Is the Lion Diet?

The Lion Diet is a highly restrictive elimination pattern that limits food intake to ruminant meat, salt, and water. It was created by Mikhaila Peterson, a lifestyle blogger and podcast host who claims the approach helped improve her autoimmune symptoms. Her father, psychologist Jordan Peterson, also became a vocal adherent, which helped the diet gain viral attention on social media.

Unlike the broader carnivore diet (which allows all animal products including poultry, fish, eggs, and dairy), the Lion Diet permits only meat from ruminant animals—beef, lamb, goat, bison, and deer—plus their fat and drippings. Everything else is excluded: all plants, all seasonings beyond salt, coffee, tea, and even other animal foods.

The theory behind it is that by stripping your diet down to the most basic foods, you can "reset" your system and then reintroduce other foods one by one to identify triggers. However, there's no standardized clinical protocol, no set duration, and—critically—no clinical trials specifically studying the Lion Diet. According to Cleveland Clinic registered dietitian Maria Garcia Luis, "most of the claims out there are anecdotal and based on individual testimonials."

What the Research Actually Shows

While proponents share compelling personal stories, the scientific picture is more complicated. A 2021 survey of over 2,000 carnivore diet followers (published in Current Opinion in Endocrinology, Diabetes and Obesity) found that participants reported few adverse effects and high satisfaction. However, the study also noted that LDL cholesterol levels were "variably affected," and the authors emphasized that "the generalizability of these findings and the long-term effects of this dietary pattern require further study."

Harvard T.H. Chan School of Public Health's Walter Willett has been more direct, calling the carnivore diet a "terrible idea" because it eliminates fiber, carotenoids, and polyphenols—compounds linked to lower risk of chronic diseases like type 2 diabetes and certain cancers. The Lion Diet, being even more restrictive, amplifies these concerns.

On fiber specifically: the Academy of Nutrition and Dietetics recommends 25-38 grams of fiber daily for adults. The Lion Diet provides zero. "Without fiber, you reduce the microbial diversity in your gut," Garcia Luis explains. "This directly affects your digestive health and immune regulation."

For a deeper dive into why fiber matters so much, our Ultimate Guide to Dietary Fiber covers the science behind its role in gut health, heart health, and weight management.

The Red Meat and Cancer Question

One concern that deserves direct attention: the relationship between red meat consumption and colorectal cancer. The International Agency for Research on Cancer (IARC) classifies processed meat as a Group 1 carcinogen (meaning there's sufficient evidence it causes cancer) and red meat as Group 2A (probably carcinogenic).

A 2025 prospective study published in Nature Communications, examining over 542,000 women and 12,251 colorectal cancer cases, found that red and processed meat were the only dietary factors (besides alcohol) positively associated with colorectal cancer risk. A 30-gram daily intake increased risk by 8%.

The World Cancer Research Fund and American Institute for Cancer Research recommend limiting red meat to no more than 12-18 ounces (cooked weight) per week—roughly three palm-sized portions. Their guidance on processed meat is even stricter: consume very little, if any. A Lion Diet, by design, would far exceed these recommendations.

Cardiovascular and Other Health Concerns

The Lion Diet's high saturated fat content raises additional flags. "This diet is high in saturated fats and cholesterol, and that leads to an increase in your LDL, or your 'bad' cholesterol," warns Garcia Luis. Harvard Health notes that carnivore-style diets are associated with increased risk of kidney stones, gout, and osteoporosis, and that very high protein intake can impair kidney function in some individuals.

A 2025 systematic review in Nutrition and Health examined the protein paradox in carnivore diets, concluding that while meat is effective for muscle building and short-term energy, "a carnivore diet holds too many adverse long-term side effects to be considered a staple for a longevity-based diet."

Who Should Definitely Avoid This Diet

Certain groups face heightened risks. The Lion Diet is not appropriate for people with cardiovascular risk factors, elevated LDL cholesterol, kidney disease, gout, or history of kidney stones. Anyone with or at risk for disordered eating should avoid highly restrictive protocols that could trigger unhealthy patterns. Pregnant or breastfeeding individuals need the nutritional variety this diet eliminates, as do children and teens.

If you're on medications affected by rapid diet shifts—blood thinners, diabetes medications, blood pressure drugs—coordinate closely with your healthcare provider before making dramatic dietary changes.

A Smarter Approach to Finding Food Triggers

If identifying food sensitivities is your goal, there are evidence-based alternatives that don't require eliminating entire nutrient categories. The Autoimmune Protocol (AIP) is one such approach with actual clinical trial data behind it.

A 2024 review in Metabolism Open examined AIP's use for autoimmune diseases and found it offers a structured framework: an elimination phase that removes potential triggers (grains, legumes, nightshades, dairy, eggs, and certain additives), followed by systematic reintroduction to identify individual sensitivities. Unlike the Lion Diet, AIP retains vegetables, fruits, and other nutrient-dense foods throughout.

Clinical trials on AIP for inflammatory bowel disease have shown promising results. One study found that 73% of participants with active IBD achieved clinical remission by week 6 of the protocol—while still maintaining nutritional balance. A 2024 update to the protocol (Modified AIP) made it even more accessible by allowing foods like rice and legumes that research showed were rarely problematic.

For a comprehensive look at foods that support both weight management and overall health without extreme restriction, our Complete Guide to the Best Foods for Weight Loss breaks down the evidence-backed options.

The Bottom Line

The Lion Diet offers a seductively simple premise: eat only meat, feel better. And for some people, at least in the short term, it may provide symptom relief—though whether that's due to removing specific triggers, reducing overall food variety, or placebo effect is impossible to know without controlled studies.

What we do know is that medical professionals don't recommend it. The diet lacks clinical evidence, eliminates essential nutrients, and runs counter to established guidance on red meat consumption and disease prevention. As Garcia Luis puts it: "I'll always advocate for a more balanced, evidence-based approach to nutrition that ensures you have an adequate intake of essential nutrients your body needs."

If you're struggling with unexplained symptoms and want to explore dietary factors, work with a registered dietitian who can guide you through a structured elimination protocol that doesn't sacrifice your nutritional foundation in the process.

Make It Easier

Looking for balanced, protein-forward meals that support your health without extreme restriction? Explore our rotating High-Protein Meal Plans, customize proteins and sides with Build-a-Meal Plan, and check macros on our Nutrition Info page.

FAQs

Will the Lion Diet make me lose weight?

Many people lose weight on highly restrictive diets due to limited food choices and higher protein content. But sustainability is low, and long-term health tradeoffs (elevated LDL cholesterol, zero fiber intake) matter. For durable fat loss, a calorie-appropriate, high-protein, high-fiber approach is more effective and safer.

Is the Lion Diet safe long-term?

No. Major health organizations recommend limiting red meat to 12-18 ounces per week and emphasize fiber-rich plant foods for disease prevention. The Lion Diet far exceeds red meat recommendations while providing zero fiber. It was never designed for long-term use, even by its creator.

Is the Lion Diet different from keto?

Yes. Keto manipulates macros (very low carb, higher fat) but can include vegetables, nuts, dairy, and other non-meat foods. The Lion Diet eliminates everything except ruminant meat, salt, and water—making it far more restrictive.

What's a safer alternative for identifying food triggers?

The Autoimmune Protocol (AIP) offers a clinician-tested framework that eliminates potential triggers while maintaining nutritional balance. Clinical trials show it's effective for conditions like IBD, and a 2024 modified version makes it even more accessible. Work with a registered dietitian for personalized guidance.

Related Reads

What Is the Dr. Now Diet?
What Foods Are Good for Weight Loss?
Top 10 Healthy Lunch Ideas
Best & Worst Snack Foods

References

Cleveland Clinic (November 2025): Registered dietitian Maria Garcia Luis on Lion Diet risks and lack of clinical evidence. Cleveland Clinic

Carnivore diet survey (2021): Lennerz BS, et al. "Behavioral Characteristics and Self-Reported Health Status among 2029 Adults Consuming a 'Carnivore Diet.'" Current Opinion in Endocrinology, Diabetes and Obesity. PMC

Harvard T.H. Chan School of Public Health (2024): Walter Willett on carnivore diet concerns. Harvard Chan

Red meat and colorectal cancer (2025): "Diet-wide analyses for risk of colorectal cancer: prospective study of 12,251 incident cases among 542,778 women in the UK." Nature Communications. Nature

WCRF/AICR recommendations: Limit red meat to 12-18 oz/week cooked; avoid processed meat. AICR

AIP review (2024): Pardali EC, et al. "Autoimmune protocol diet: A personalized elimination diet for patients with autoimmune diseases." Metabolism Open. PMC

AIP for IBD (2017): Konijeti GG, et al. "Efficacy of the Autoimmune Protocol Diet for Inflammatory Bowel Disease." Inflammatory Bowel Diseases. PMC

Carnivore diet and longevity (2025): Palmer RD. "The protein paradox, carnivore diet & hypertrophy versus longevity." Nutrition and Health. SAGE Journals

Harvard Health on carnivore diet: Howard LeWine, MD on LDL cholesterol, kidney stones, and gout risk. Harvard Health