A nutritionist's review of the Carnivore Diet

How does it work?

Those who advocate this diet recommend eating exclusively animal-based foods, and cutting out all plant-based foods (you could call it the ‘Anti-Vegan Diet’). It’s heavily focused around eating meat, with the aim to eradicate all carbohydrates from the diet.

Supporters of this diet believe we should live like our ancestors, who they believe lived solely off animals (even though the general consensus is that we have always eaten a combination of plants and animals).

Typical foods included:

• Beef
• Pork
• Lamb
• Offal
• Chicken
• Turkey
• Fish
• Eggs
• Bone marrow
• Butter/ghee
• Some also choose to include a small amount of low-lactose cheese, yogurt and milk

Foods excluded:

• Fruits
• Vegetables
• Grains
• Pulses
• Nuts and seeds
• High-lactose dairy foods
• All processed foods high in sugar

What are the benefits?

Since this diet only really regained popularity less than 10 years ago, there is no robust scientific evidence to support its long-term safety of it in the long-term. Much of the reported benefits are anecdotal with followers claiming it helps with things such as weight loss, blood sugar control, reducing inflammation and mood control.

One study took self-reported information from participants who had chosen to follow a carnivore diet for more than 6 months and concluded that followers of the diet felt it benefited their health (1). While no immediate health concerns had presented themselves to the participants during the average 14-month adoption of a carnivore diet, thorough testing for deficiencies was not conducted. It’s also worth noting that more than 60% of the participants did say they took supplements – highlighting the nutritional gaps present in this diet. Also, LDL cholesterol was found to be elevated, which is a risk factor for heart disease.

While anecdotally followers may state that they feel some benefit to following this diet, it must be stressed that there could be some harm being caused in a less immediately visible way. Without more thorough long-term research it’s not possible to comment on the safety of this diet.

What are the drawbacks?

This diet essentially goes against the healthy eating guidance we have here in the UK. Here are some key areas of concern:

Recommends large amounts of meat – with no real guidance on the quality or type of meat. Many followers of this diet consume large amounts of red meat and in some cases processed meats. Current healthy eating guidelines advise we limit our red and processed meat intake to no more than 500g per week – since this amount would provide about 600-650 calories, one could assume those following a carnivore diet would be consuming significantly more than this! The World Cancer Research Fund supports this health guidance and states that there is strong evidence that eating large amounts of red and processed meats can increase the risk of bowel cancer (2).

Poses a risk of nutrient deficiencies – due to the removal of many foods in this diet, those nutrients which are typically present in plant foods such as vitamin C, fibre and magnesium could be lacking in the diet. One study found that while a typical carnivore diet met the nutritional guideline intakes for things like B vitamins, Vitamin A, zinc and selenium, it didn’t meet those for vitamin C, magnesium, folate, iodine, potassium and calcium (3).

Not gut-friendly – you can’t have failed to notice the hype around gut health at the moment, with the focus here being on plant-food variety. We also know that the only source of fibre in our diet is carbohydrate-based foods and fibre is important for gut health - so the complete removal of these foods from our diet means our poor guts are not receiving the nutrients they need to thrive and function well.

Not planet-friendly – now more than ever we should all be paying attention to the environmental impact of our day-to-day choices, and for the individual, our diet is high up on the list of considerations. One thing we’re all being asked to consider is reducing our meat intake due to the environmental impact of meat production (4). The carnivore diet is therefore going against this planet-friendly guidance, which should be a consideration if choosing this dietary approach.