Medically reviewed by Allison Herries, RDN Low-carb fruits include watermelon, berries, avocado, cantaloupe, and more.

Keto diets restrict the amount of carbohydrates a person can eat. Instead, a person eats a high amount of fats and a moderate amount of protein. Keto diets aim to put the body into a state of ketosis.

The low-carb, high-fat ketogenic diet has been promoted online and in the media as a weight-loss tool and seemingly all-round magical healer. Yet it was first developed in the 1920s for children ...