You can hardly open a magazine these days or you’ll read about the Keto diet: Keto was a common search term for diets on Google in 2018. But what exactly is the hype about?

What is the Keto diet?

‘Keto’ stands for Ketogenic diet, an extreme form of the low-carbohydrate diet. In short, this involves eating large amounts of fats, a modest amount of protein and very few carbohydrates. But it is certainly not a matter of “eat as you please. Ideally, on the Keto diet, you get about 70 to 80 percent of your daily calories from fats, about 10 to 20 percent from protein and about 5 to 10 percent from carbohydrates [i].

Fat contains more calories per gram than carbohydrates and protein. When you eat more calories than your body needs, it can eventually lead to weight gain. But it is possible to lose weight with a diet focused on fat, as long as you stick carefully to the program. Initially, you lose weight because your body loses fluid in response to the drastically reduced intake of carbohydrates. Because you have to omit a lot of foods from your normal diet (in this case carbohydrates) you may also start eating less, which will cause you to lose even more weight.

There is some evidence that you can lose fat if a large portion of your calories come from fat. Here’s how this works: The cells in your body normally prefer to get their energy from glucose (sugars that come from the carbohydrates you ingest) [ii]. If you follow a diet with very few carbohydrates and lots of fats, your body switches from burning sugar to burning fat. This process takes place in the liver, releasing as a byproduct so-called Ketones, which are an alternative source of energy [iii].

Whether you follow a high-carb or low-carb diet, you only lose weight if you eat fewer calories than your body burns

^{[i]https://www.hsph.harvard.edu/nutritionsource/healthy-weight/diet-reviews/ketogenic-diet/
[ii] https://www.health.harvard.edu/blog/ketogenic-diet-is-the-ultimate-low-carb-diet-good-for-you-2017072712089
[iii] https://www.health.harvard.edu/staying-healthy/should-you-try-the-keto-diet}