In the keto diet world, there are two types of people: Those who are all for the high-fat lifestyle, and those who, well, aren’t.
Jenna Jameson, for example, is clearly a proponent—as is Mama June, Halle Berry, and Savannah Guthrie. Jenna, for example, credits the keto diet with her more than 60-pound postpartum weight loss, while Halle swears that it helps her maintain her health (she has type 2 diabetes).
But, like any super-polarizing trend, the keto diet isn’t universally loved: Tamra Judge, who was on the keto diet for about a month, recently quit, saying it “doesn’t do anything,” except, you know, make her sick (#ketofluproblems).
Amid all the positive and negative reviews, though, you may still be a little hazy on the details of the keto diet—like what it is, how it works, and exactly how much butter and cheese you get to eat. Don’t worry, I got you.
ALL RIGHT, WHAT EXACTLY IS THE KETO DIET?
Short for “ketogenic diet,” this eating plan is all about minimizing your carbs and upping your fats to get your body to use fat as a form of energy, says Scott Keatley, R.D., of Keatley Medical Nutrition Therapy. While everyone’s body and needs are slightly different, that typically translates to: 60 to 75 percent of your calories from fat, 15 to 30 percent of your calories from protein, and 5 to 10 percent of your calories from carbs.
After about two to seven days of following this eating routine, you go into something called ketosis, or the state your body enters when it doesn’t have enough carbs for your cells to use for energy. Then it starts making ketones, or organic compounds that your bod then uses in place of those missing carbs—and oh, it also burns fat for more energy, says Beth Warren, R.D., founder of Beth Warren Nutrition and author of Living A Real Life With Real Food.
WHY DID THE KETO DIET BECOME SO TRENDY FOR WEIGHT LOSS?
Believe it or not, keto was designed to help people who suffer from seizure disorders—not to help people lose weight, says New York-based R.D. Jessica Cording. That’s because both ketones and another chemical produced by the diet, called decanoic acid, may help minimize seizures.
But people who started following the keto diet noticed weight loss for a few reasons: When you eat carbs, your body retains fluid in order to store carbs for energy (you know, in case it needs it). But when you’re not having much in the carb department, you lose this water weight, says Warren. Also, it’s easy to go overboard on carbohydrates—but if you’re loading up on fat, it may help curb cravings since it keeps you satisfied.
That, plus the fact that ketosis encourages your body to burn fat, means you can end up with pretty dramatic weight loss.
“The keto diet took off because its ‘rules’ make sense to most people,” Keatley says. “Almost all of us want to lose some fat from somewhere on our body, and this diet focuses on fat as fuel.”
Celebs who’ve done the keto diet didn’t exactly hurt its rep, either.
OKAY, SO WHAT FOODS CAN (AND CAN’T) I EAT ON THE KETO DIET?
Because you’ll be focusing on fat and protein—and going easy on the carbs—big bowls of pasta definitely won’t be on your menu…but that doesn’t mean you’ll go hungry.
You’ll be loading up on healthy fats (like olive oil and avocado), along with plenty of lean protein and leafy green veggies.