The keto diet could be considered the OG of fad diets. William Banting, a London funeral director, accidentally discovered his own meaty version of the plan in the 1860s and authored a wildly popular how-to booklet, losing a total of over 50 pounds on his "Banting Diet".
On a well-planned ketogenic diet, people get 70-80% of their daily calories from fat, another 20-25% from protein sources, and consume very few carbohydrates. Keto dieters are thus known for filling up on ketogenic-friendly staples like cauliflower, eggs, cheese, and meat, while avoiding grain-based breads, pastas, and other high-carb foods including apples and carrots.
Ketogenic diets can be also doctor-recommended under the right circumstances; it's a well-established way to help control Type 2 diabetes, and the plan has for nearly 100 years been used to reduce instances of childhood epileptic seizures.
But if people aren't careful about how they approach it, the fatty routine can be disastrous.
Relying too much on protein-packed foods like red meat and cream, while not getting enough essential nutrients from plants can cause dieters to raise up their odds of developing health problems like gout while putting extra stress on the kidneys.
It typically takes around five days for a person's body to enter the ketosis fat-burning state, and this diet shouldn't ever be treated as a quick-fix yo-yo plan for a little extra flab.
"You need to be committed," cancer researcher David Harper, who's been on a keto diet himself for six years, previously told Business Insider.