The Lion Diet: Everything you need to know

Feb 04, 2024

It’s the latest health trend, but does the lion diet actually work? Here’s what two experts think

If you thought the carnivore diet was extreme, then ready yourself because the ‘Lion Diet’ – currently trending on TikTok – takes it to another level. Fans of the diet claim it helps with a host of health issues, such as allergies, insomnia, mood disorders, skin problems, inflammation and an unhappy gut. But is there any substance to the claims? And would a lion diet work for those with an active lifestyle? We’ve spoken to two experts who’ve shared their thoughts on the diet and whether they think it’s a safe and effective plan to follow. Here’s everything you need to know.

What is the Lion Diet?

Consisting of eating meat from ruminant animals (such as cows, deer, sheep and goats), salt and water for at least six weeks, the extreme concept is the brainchild of podcaster and blogger Mikhaila Fuller. Declaring it a ‘healing elimination diet’, Fuller credits the diet for having significantly helped her with reducing joint pain, clearing up rashes and alleviating the symptoms of depression and chronic fatigue. While Fuller has since detailed falling ill again, she blames mould and biotoxins for this and says she is still on the lion diet.

‘The lion diet seems to be this year’s take on the paleo/keto/carnivore trend,’ says registered dietitian, Laura Kaar. ‘As with so many new “health” trends, this is based on one-person anecdotal experience, as opposed to the robust scientific evidence that guides dietary guidelines.’

Fuller says followers of the plan can think of it as a ‘plant-free, ketogenic diet’ and advises them to eat just ruminant meat, salt and water for at least six weeks. While there is no requirement to follow the diet for longer than six weeks, she says undertaking it for a period of at least three months seems to be most useful.

Followers of the diet may experience flu-like symptoms, or ‘keto-flu’, for the first few days, adds Fuller, explaining that side effects, such as loose stools, mental fog, muscle cramps and fatigue should pass within two weeks.

Once followers of the lion diet are asymptomatic, as Fuller puts it, they can re-introduce foods that are ‘least likely to cause autoimmune or mood flare-ups,’ such as salmon, mackerel, tuna, corn and soy-free chicken and honey. The fish, though, must not be canned or smoked and has to be wild, not farmed, says Fuller. If the body reacts well over a few days to the re-introduction of these foods, then pressure-cooking organic carrots and parsnips in broth and drinking the broth can be trialled. If that goes well, peeled and cooked apples, pears, carrots, parsnips, beetroot, sweet potatoes, coconut, lettuces, duck and pasture-raised chicken are then okay to start being introduced, she says.

Fuller calls the lion diet ‘the closest thing you can get to a whole food elimination diet,’ but what exactly is an elimination diet?

‘An elimination diet can be incredibly helpful and essential in some conditions and for some allergens,’ says Kaar. ‘However, they need to be done with the guidance of a dietitian and doctor to ensure safety.’ They are also usually short-term. The biggest part of elimination diets that people forget, says Kaar, is the re-introduction or challenge phase, which is key to preventing long-term unnecessary restrictions. She points to the low FODMAP diet used for managing Irritable Bowel Syndrome (IBS). ‘While there is an initial restriction phase, the staged food challenges in the re-introduction phase are key to identifying a person’s triggers and reintroducing variety,’ she adds.

So, does the lion diet work? ‘Without robust evidence, it is simply impossible to say,’ says Kaar. Specialist registered dietitian, Nichola Ludlam-Raine adds that although proponents of the diet praise it for weight loss or improved mental clarity, these claims are not well-supported by scientific research. ‘Any weight loss is likely due to the extreme restriction of calories rather than a specific benefit of the diet itself,’ she explains, pointing out that the lack of essential nutrients and potential health risks far outweigh any perceived benefits.

Kaar says that, simply put, she doesn’t think it’s worth trying and would instead advise anyone with gastrointestinal symptoms who is struggling with a healthy balanced diet to speak to their doctor and see a dietitian for specific tailored evidence-based advice.

‘The lion diet is not recommended for most individuals, especially athletes like runners, who require a balanced diet to support their energy needs,’ explains Ludlam-Raine. ‘The lack of carbohydrates, fibre, and various vitamins and minerals could lead to fatigue, poor performance, and potential health risks.’

Kaar agrees: ‘The biggest red flag is the lack of carbohydrates, which the body uses for energy and so is especially important for runners and people regularly exercising with performance goals.’ While following a very specific low-carb diet, can trigger ketogenesis (where the body uses stored and dietary fat for energy), your body is at risk of breaking down muscle for energy alongside this, she warns. ‘Building muscle is hard and gets harder as we age,’ Kaar stresses. ‘We should be prioritising maintaining muscle for performance goals, longevity and metabolic health.’

Fuller says that it’s possible to get all the nutrients that you need from ruminant meat, but the experts disagree. Neither Karr nor Ludlam-Raine would advise trying the lion diet.

‘The lion diet poses significant risks,’ says Ludlam-Rane listing nutrient deficiencies (such as a lack of vitamin C, vitamin E, and certain B vitamins), constipation due to lack of fibre, increased risk of heart disease due to high saturated fat intake and potential negative impacts on kidney function as some of the dangers. Kaar adds that the diet also lacks beneficial phytochemicals, and both point to the lack of diversity and fibre crucial for a healthy gut microbiome.

Kaar says: ‘In short, there is no evidence that this diet should be recommended for any mental or physical health condition.’

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