By Kelsey Casselbury
In the 1980s, the low-fat diet fad swept the nation. Research is mixed on how well that worked out for public health in general, but now people hoping to shed weight are turning the other way—to the keto diet (short for ketosis), a high-fat, low-carbohydrate way of eating that goes against everything that people once did in the name of weight loss.
The Gist
The ketosis diet was once used solely to control seizures in epileptics who do not respond to medication. It’s a low-carb, high-fat diet (with a medium amount of protein) that is very restrictive. It’s essentially the first two weeks of the Atkins diet, if you’re familiar with that—it keeps
carbohydrates to just 20 grams a day. For reference, a 3.5-ounce bagel has 48 grams of carbohydrates.
The Science
Your body turns carbohydrates into glycogen, which it stores in the muscles and liver and uses for energy. When carbs get low, glycogen supplies are depleted, and your body goes into a state known as ketosis. When this happens, your liver releases ketones (fatty acids from your diet or body stores) that your body then uses for energy. In other words, you burn fat instead of carbs. However, there’s another reason that keto might work—when you cut out so many foods, it automatically reduces the number of calories that you eat. Fewer calories typically means weight loss.
Drawbacks
First, it’s really hard to stay strict on a diet that doesn’t allow for any sugar—that means no chocolate, no wine, no pasta. For some, that’s just not going to happen. Additionally, a keto diet plan is often high in saturated fats because it allows people to eat bacon, cheese, red meat, and other full-fat animal products willy-nilly. At the beginning of the year, health experts at U.S. News and World Report ranked keto dead last on its list of best and worst diets (DASH ranked No. 1). On the other hand, if you follow the diet appropriately, it’s also full of vegetables—and that never hurt anyone.
What's Allowed
-Animal protein sources, such as red meat, eggs, poultry, and fish
-Fats and oils, including butter, coconut oil, and olive oil
-Vegetables that grow above the ground, such as leafy greens
-Most full-fat dairy
-Nuts and seeds
-Coffee
-Berries (in strict moderation)
-Hard liquor (in strict moderation)
What's Not
-Any proteins made with sugar, such as maple-smoked bacon
-Sources of sugar, like honey and maple syrup
-Starchy vegetables, such as potatoes and corn
-Grains
-Beans and other legumes
-Low-fat dairy products
-Processed vegetable oils (peanut, sesame, sunflower oil, to name a few)
-Most fruits and juice
-All soda, even diet
-Artificial sweeteners
-Beer, wine, cocktails, and flavor liquors
