The ketogenic diet is a high-fat, moderate-protein, and low-carbohydrate diet that has been used for over a century to treat certain medical conditions, such as epilepsy. More recently, it has gained popularity as a weight loss and general health-promoting diet.  The goal of the ketogenic diet is to put the body into a metabolic state called ketosis, in which it uses ketones (small molecules produced in the liver from fat) as its primary fuel source instead of glucose (which comes from carbohydrates).

By limiting carbohydrate intake, the body is forced to use stored fat for energy, resulting in weight loss and other potential health benefits.  Typically, a well-formulated ketogenic diet involves consuming 70-80% of calories from fat, 20-25% from protein, and only 5-10% from carbohydrates. This translates to a daily intake of 20-50 grams of carbohydrates for most people, although individual needs may vary.  Foods that are allowed on a ketogenic diet include healthy fats such as avocado, nuts and seeds, coconut oil, olive oil, and fatty fish; moderate amounts of protein from sources such as meat, eggs, and dairy; and low-carbohydrate vegetables such as leafy greens, broccoli, and cauliflower.

Foods that should be avoided or limited on a ketogenic diet include high-carbohydrate foods such as grains, legumes, fruit, and starchy vegetables; as well as processed and sugary foods.  Research suggests that a well-formulated ketogenic diet may offer several potential health benefits, such as:

Weight loss: By limiting carbohydrate intake and promoting the use of stored fat for energy, the ketogenic diet may help people lose weight and improve body composition.

Improved blood sugar control: The ketogenic diet may help regulate blood sugar levels and improve insulin sensitivity, which can be beneficial for people with diabetes or prediabetes.

Reduced inflammation: The ketogenic diet may have anti-inflammatory effects, which could be beneficial for people with conditions such as arthritis or other inflammatory disorders. Reduced risk of certain diseases:

Some studies suggest that the ketogenic diet may help reduce the risk of certain diseases, such as cancer, Alzheimer's disease, and cardiovascular disease. However, more research is needed to fully understand these potential benefits.

Despite its potential benefits, the ketogenic diet may not be suitable for everyone. Potential risks and side effects may include Nutrient deficiencies: Because the diet restricts certain food groups, such as fruits and grains, it can be difficult to get all the necessary nutrients, such as fiber and vitamins, without careful planning.

Digestive issues: Some people may experience digestive issues such as constipation or diarrhea when first starting the diet. "Keto flu": During the initial transition period, some people may experience flu-like symptoms such as fatigue, headaches, and nausea as the body adjusts to using ketones as its primary fuel source.