If you're one of Joe Rogan's 8.5 million Instagram followers, you're likely familiar with his unconventional diet. The comedian, mixed martial arts fanatic and podcast host often shares photos of his favorite meal, which consists of elk meat, mushrooms and jalapenos.
But in January, Rogan experimented eating only meat for 30 days — no carbohydrates, vegetables or fruit. This style of eating is often referred to as "the carnivore diet."
Rogan isn't the first person to try this extreme diet; psychologist Jordan Peterson spoke on Rogan's podcast in July 2018 about his experience eating only meat, and claimed it helped his mental health and energy levels. After hearing about other people who had success with the diet, Rogan was curious to see if it would help with his autoimmune condition, called vitiligo, he said on an episode of his podcast, "Joe Rogan Experience."
Rogan said he ate just two meals a day, one around noon and then dinner. For breakfast, he would eat several eggs, and then grass-fed elk or beef steak for dinner. Rogan said he would also eat some bacon since elk is a lean meat. "Your body does not want a low-fat diet with low carbohydrates," he said on the podcast.
To make up for the plants and other nutrients he was missing, Rogan said he took several dietary supplements. "I'm covering all my nutritional bases, but I'm not doing it with food, [and] I'm not doing it with plants. I'm only eating grass-fed meat," he said. There were two times that he slipped up on his diet: once he ate olives, and another time he ate mango.
Surprisingly, Rogan said that he felt good. In an Instagram post Jan. 31, he said that he "lost 12 pounds and gained a lot of energy."
"My energy levels were completely flat the whole month," Rogan said in the Instagram video. "No ups and downs, no crashing after eating." Although he experienced severe gastrointestinal symptoms, such as diarrhea, he recommended that people try it. "I think you'll be amazed at how good you feel," he said on the podcast.
But experts say that this very restrictive diet can deprive you of essential nutrients that come from plant-based foods, and has the potential to harm your health long-term.
For starters, eating nothing but animal protein that's high in saturated fat while ignoring vegetables and carbohydrates is not wise, Linda Van Horn, chief of nutrition in the department of preventive medicine at Northwestern University Feinberg School of Medicine, tells CNBC Make It. Research suggests that eating two servings of red or processed meat a week is associated with an increased risk of cardiovascular disease and death.
As for Rogan's claim that this diet improved his energy levels? Nutritionally, that doesn't make a ton of sense, Van Horn says. Calories are units of energy that are found in the carbohydrates, protein, fat and alcohol that we consume. Carbohydrates are the body's preferred source of energy, because they digest quickly and easily.
If anything, the energy boost that people claim to get from the carnivore diet likely comes from losing weight, not from eating meat, Van Horn says. (Eliminating any food group from your diet could make someone lose weight, but especially carbohydrates and refined sugar, she says.) That "maybe feels like increased energy," she says.
The bottom line: fruits, vegetables and whole grains have essential nutrients and dietary fiber that you can't get from animal-based products, Van Horn says. "Regardless of where you're coming from, it would help you to increase the number of meals that are vegetable-protein based, and reduce the number that are animal-protein based," she says. (Van Horn is a fan of plant-based meat alternatives, but says that many of the products contain additives and high levels of sodium.)
Although some people might be able to temporarily tolerate an all-meat diet, studies consistently show that a high-quality diet with a variety of nutrients is associated with "better quality of life, longevity and reduced risk of chronic diseases," Van Horn says.
Luckily, there are a few ways that you can eat for energy in a healthy way. For example, the Academy of Nutrition and Dietetics recommends eating meals that are balanced, meaning they contain multiple food groups, such as whole grains, lean protein, fruits and vegetables, dairy and fat. Cutting back on foods that have lots of added sugar is another way to avoid energy crashes.
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