So what are the benefits?
As Harvey explains, the carnivore diet claims to aid weight loss, improve sleep and blood sugar regulation and reduce inflammation, which can support conditions such as rheumatoid arthritis, diabetes and mood disorders such as anxiety and depression. “Eating a very low level of carbohydrates, like you would on the carnivore diet, will reduce the amount of glucose in the body, which may help with blood sugar regulation, simply because there is less glucose coming into the body. Carbohydrates also hold water in the body, so it’s likely you will see a drop in body weight after a few days of following the diet, though it’s important to note this is simply water weight, not fat. Plus, as with many restrictive diets, it’s likely you’ll be in calorie deficit, which can aid with weight loss.” While research is lacking when it comes to the carnivore diet, studies show it’s not uncommon to lose 5kg (11lb) in the first week of the nutritionally similar ketogenic diet.
Aren’t carbs the body’s preferred source of energy?
Yes and no, says Harvey. “Carbohydrates are the body’s preferred fuel source. Some organs rely solely on glucose (the component that carbs are broken down into) to function, such as the brain and red blood cells. However, the body can produce the required amount of glucose from other parts of the diet and other cells can utilise energy produced from fat breakdown (ketones). Therefore, it is safe to cut carbs from the diet.” In short, when you eat only meat and other animal products, you force your body to burn fat instead of glucose. When your body switches its fuel supply to run on fat, insulin levels drop significantly, triggering the fat-burning process. Some studies suggest burning fat is a cleaner way to stay energised than running on carbs – by forcing the brain to burn fat instead of glucose, you avoid blood-sugar swings, resulting in supercharged concentration.
Is eating a meat-only diet safe?
The jury’s out. As with any diet that cuts out major food groups, controversy surrounding the carnivore diet is widespread. “There is no research to support many of the claims associated with the carnivore diet, and the only ‘evidence’ available that it works comes from personal anecdotes,” says nutritionist Lily Soutter. “The diet is extremely restrictive and can put individuals at risk of nutritional deficiencies. This diet lacks key micronutrients including manganese, folate, vitamin K1. Plus, the diet is extremely low in fibre, which has been linked to an increased risk of colon cancer, unhealthy cholesterol levels and diverticulosis. Furthermore, as fibre is the gut’s primary source of fuel, this low-fibre diet can impact its composition.” The potential risks don’t end there: a 2018 study found a link between eating lots of red and processed meats with non-alcoholic fatty liver disease and insulin resistance – a red flag for those with diabetes considering the carnivore diet.