It took a while, but by now most of us know that fat is not the enemy, that there are certain kinds of fat that can actually help your heart, and that it need not be obliterated from your diet if you’re trying to lose weight. In fact, for some people, fat is actually the superhero of their diet—and chowing down on olive oil, butter, and heavy cream is the key to watching the scale dive lower and lower, without feeling hungry or deprived. But can a diet heavy on the heavy cream turn out to be not unsafe—and maybe even good for you? We consulted top-shelf, unbiased sources that specialize in diet and nutrition, and were surprised to find that the answer is a resounding yes.
First, the basics about the diet. It’s called a ketogenic diet, one that’s heavy
If that sounds a bit odd, it’s not, says Passler. “The human body is designed to be able to handle times of food scarcity,” says Passler. “The trouble is, we currently have access to food 24/7, but our physiology hasn’t caught up with that yet. Say you have breakfast at 8 a.m., and then it's 1 p.m. and you think you're starving, that's just five hours. The only reason you feel that way is because you had a meal with carbs in it and your blood sugar levels have crashed, which leads you to believe your body actually needs more fuel. We make the mistake of thinking we are starving when in fact, it’s a carbohydrate roller coaster.”
By contrast, when you’re on a ketogenic diet, you have more stable blood sugar and you become a fat-burning machine. Not only that, but you’ll see the difference pretty quickly. “That’s because a big part of the glycogen in your body tissues is made of water,” says Passler. After that stash is exhausted, any puffiness or bloating will be gone and your body will immediately shrink a bit. (This is also why many bodybuilders rely on ketosis to give them a cut look during competitions.) Of course, that water-weight is not lost permanently; if you go out of ketosis, it can return. The fat you burn, however, is gone, baby gone.
Suzanne Ryan, 33, had tried just about every other diet out there before she stumbled on chatter about the keto diet in a sub-Reddit thread, in 2015. After just one month on the diet, she had lost 21 pounds; a year later, 100 pounds. Two years later, she’s down over 120 pounds but up over 100,000 Instagram followers, and while she sometimes misses being able to eat things like fruit (more on that in a second), “for the most part my tastes and preferences have changed so much. Once you break the sugar addiction you are still eating really delicious and flavorful foods.” She’s so passionate about this way of life she has created a blog, KetoKarma.com, and will publish a cookbook, Simply Keto, in December.
Some of the diet specifics may surprise you. For instance, not all vegetables get a complete green light. You can have as many leafy greens as you want, but certain veggies, like potatoes and onions, are higher in carbs and should be moderated. For fruit, you can eat most
A typical keto dieter's day is about 60-80% fat, 20-30% protein, and 10% carbohydrates. For Ryan, her eating plan may look like this: Coffee in the morning with heavy cream, plus two scrambled eggs with avocado; lunch is a lettuce-wrapped sandwich of egg salad or turkey or ham with mayo; dinner is chicken, steak, or seafood with cauliflower mash or veggies with butter. “With
And those with less weight to lose than Ryan—but with photo shoots to prep for or certain chronic illnesses—also sing the diet’s praises, saying it’s far less difficult or restrictive than you might imagine. “You can have so many filling foods on this diet, and you feel great, especially in the morning,” says Sarah Biehler, a model and actress in New York City, who works with
While there are some critics who knee-jerk fret about how a high-fat diet can impact your cardiovascular health, if you look more carefully at it, this can be a safe, effective diet, says David Ludwig, MD, PhD, a professor of nutrition at Harvard University, and author of Always Hungry. “Ketogenic diets are actually great for triglycerides and HDL levels, and can lower insulin levels,” but it can definitely be different for everyone. Some people see an increase in cholesterol and others don’t, says nutritionist
Ryan found that her body reacted well to keto. When she went to visit her doctor after being on the diet for a year, her blood work showed that her cholesterol levels and rations were better than ever. “She was unsure of my doing keto at first—she’d always handed me sheets about low-fat diets—but now she has even recommended keto to some of her other patients,” says Ryan.
Getting through the first few days or week can be the biggest hurdle, notes Passler, as your body goes through the remaining glucose and then converts to ketones. (It's called the "keto flu":
There are some concerns, however, with loss of muscle mass on
A large-scale study published last month in the Lancet gave keto devotees reason to toast. The researchers found that people eating loads of carbs had a nearly 30 percent higher risk of dying during the study than people eating a low-carb diet. Compare that to those eating high-fat (or keto) diets: the study found they had a 23 percent lower chance of dying during the seven years of followup compared to people who ate less fat.
The biggest issue, say some experts, is sustainability in the long term—at least from a lifestyle perspective. “The diet is sustainable if you are a planner,” says Gabrielle Lyon, DO, an osteopathic physician and integrative medicine specialist at The Ash Center in New York City, “in the sense that you would need to make sure the meals you eat are within the keto 'sweet spot.'" If you are a person that eats out a lot you will probably find this diet difficult to follow successfully. And then there’s something Lyon calls “palate fatigue”— being sick of the same food over and over again. Successful keto dieters, however, counter that the weight loss is better than any carb
Before you start piling on the butter and kicking carbs to the door, study up and keep a few more things in mind. Keto diets can leave you dehydrated (as the glycogen is depleted your body will not hold as much water), says Lyon, so you should take a
Curious to know what a typical keto recipe looks like? Here's one for a cheesy low-carb risotto, hold the rice and replace with cauliflower. For more recipes, check out sites like:
