It’s advertised as a weight-loss wonder, but this eating plan is actually a medical diet that comes with serious risks.
In the world of weight-loss diets, low-carbohydrate, high-protein eating plans often grab attention. The Paleo, South Beach, and Atkins diets all fit into that category. They are sometimes referred to as ketogenic or “keto” diets.
But a true ketogenic diet is different. Unlike other low-carb diets, which focus on protein, a keto plan centers on fat, which supplies as much as 90% of daily calories. And it’s not the type of diet to try as an experiment.
“The keto diet is primarily used to help reduce the frequency of epileptic seizures in children. While it also has been tried for weight loss, only short-term results have been studied, and the results have been mixed. We don’t know if it works in the long term, nor whether it’s safe,” warns registered dietitian Kathy McManus, director of the Department of Nutrition at Harvard-affiliated Brigham and Women’s Hospital.
How does the keto diet work?
Here are the basics of keto: The diet aims to force your body into using a different type of fuel. Instead of relying on sugar (glucose) that comes from carbohydrates (such as grains, legumes, vegetables, and fruits), the keto diet relies on ketone bodies, a type of fuel that the liver produces from stored fat.
Burning fat seems like an ideal way to lose pounds. But getting the liver to make ketone bodies is tricky:
It requires that you deprive yourself of carbohydrates, fewer than 20 to 50 grams of carbs per day (keep in mind that a medium-sized banana has about 27 grams of carbs).
It typically takes a few days to reach a state of ketosis.
Eating too much protein can interfere with ketosis.
What do you eat?
Because the keto diet has such a high fat requirement, followers must eat fat at each meal. In a daily 2,000-calorie diet, that might look like 165 grams of fat, 40 grams of carbs, and 75 grams of protein. However, the exact ratio depends on your particular needs.
Some healthy unsaturated fats are allowed on the keto diet — like nuts (almonds, walnuts), seeds, avocados, tofu, and olive oil. But saturated fats from oils…