What is keto?
Keto is short for ketogenic and refers to diets that cause your body to burn fat as its primary energy source rather than carbohydrates. Ketosis is the name for this effect. Normally the body will break down carbohydrates into sugars to use as fuel. Ketogenic diets limit the amount of carbohydrates you consume, making your body rely on fat stores for fuel instead. When the body doesn't have these sugars from carbohydrates to fuel it, the liver will break down fats and turn them into a chemical known as ketones. The brain uses these ketones as fuel.
What are the benefits?
Since a ketogenic diet limits the amount of sugar in the body, it lowers blood-sugar and increases insulin-sensitivity, which might help control diabetes. These effects have also been shown to aid in weight-loss. The loss of excess weight has been linked to lower chances of other diseases. There is no conclusive evidence one way or the other to prove that eating a keto diet offers protection against other diseases, aside from the weight-loss, but there have been plenty of studies that suggest that it could be possible. AuthorityNutrition.com offers a breakdown of which studies have linked a keto lifestyle to decreased instances of disease.
So I just stop eating carbs?
Many people are afraid to try a ketogenic diet because they've been taught that it's dangerous to stop eating carbs. While cutting out all carbs would be bad, keto is a low-carb lifestyle, not a no-carb lifestyle. More specifically, it's low-carb, high-fat, moderate-protein. The diet generally cuts out processed carbs, refined sugars, and starches. This means you're cutting out bread, pasta, and potatoes, but can eat all the vegetables you want.
Depending on your specific needs, you might also limit the amount of higher carb fruits and vegetables in your diet. Some people cut these things out completely, but only for a short period of time. Once your body is keto-adapted, usually within 4 weeks, you can slowly add these foods back into your diet as long as you are still making progress towards your goals. If you are not using this diet for weight-loss, or are already close to your ideal weight, you can usually skip this step.
How many carbs should I eat?
There are a few different types of keto diets. The first two types are the most well-known and well-researched. The last two types are commonly used by body-builders. The percentages refer to the portion of calories coming from each macronutrient rather than the specific number of grams.
Standard-Keto: This diet has a ratio of 5% carb, 75% fat, and 20% protein. Most studies of ketogenic diets were done using this version.
High-Protein-Keto: The ratio for this diet is 5% carb, 60% fat, and 35% protein. This can be useful for those trying to put on muscle-mass and lose weight at the same time.
Cyclical-Keto: This version is a type of carb-cycling. Rather than having specific macronutrient ratios, it uses a ratio of low-carb days to high-carb days. The most common is 5:2.
Targeted-Keto: This version can also be a type of carb-cycling. It involves eating a low-carb diet as a default, but adding additional carbs on workout days.
Feel free to experiment with these versions and find which works best for you.