The ketogenic diet (keto for short), is a diet that highly restricts carbohydrates, moderately restricts protein and is high in fat intake. The concepts of the keto diet are very similar to other low carb diets, such as the Atkins diet that gained popularity in the late 1990s but has been in practice since the 1960s. Although keto sounds like a new diet concept, doctors have been using the ketogenic concept to treat patients with epilepsy since the early 1920s.
In the keto diet, carbohydrate intake is limited to 5-10%, fat intake can be anywhere from 60-90%, and protein intake moderately ranges anywhere from 15-20% of total calorie intake. When it comes to fuel in the body, carbohydrates are the preferred source. Once consumed, carbohydrates are converted into glucose for more immediate fuel needs, and excess carbohydrates are converted into glycogen and stored in the body for future fuel needs. When carbohydrates are so severely limited in the diet, the body has no choice but to use fat as its primary fuel source once the glycogen stores are depleted. During this process, fat is turned into ketones in the liver, which can supply energy for the brain. Once the body is in a ketogenic state, it becomes very efficient at burning fat. This can lead to large amounts of weight loss, especially in a person who has traditionally eaten the standard American diet, which generally consists of 50% or higher daily carbohydrate intake [Retrieved from: Healthline.com].
Many people who follow the keto diet see quick and drastic results for a few reasons. The immediate weight loss can be attributed to water weight loss. For every one gram of carbohydrates stored in the body as glycogen, the body retains 2-3 grams of water. As the body uses the glycogen, it expels all water stored and can feel like an initial boost to weight loss. Generally this leads to enhanced adherence to the ketogenic program, because of the feelings of success felt right away. Once the body enters a state of ketosis after about 2-3 weeks, the loss of fat can be substantial.
Another benefit of the ketogenic diet can be its ability to keep people feeling satiated, mainly due to the filling qualities of most fats, which can lead to eating less. Since a main component of diet success is ingesting less calories than used for fuel, this also contributes to feelings of success in the program. Many foods that are high in fats are also generally enjoyed foods-such as bacon, sausage, dairy/cheeses, and butter. The satiation and enjoyment can make it easier to adhere to such a restrictive diet plan.
Generally speaking, any high fat foods are allowed. This includes nuts, seeds, dairy (cheese, whole milk, sour cream, cottage cheese, greek yogurt with no added sugars), high fat meats (bacon, sausage, steak, pork) and non starchy vegetables, such as spinach, kale, broccoli. Other vegetables and fruits can be eaten very restrictively as part of a daily keto diet, but would need to be tracked precisely to keep overall carbohydrate intake at the ketogenic range of 5-10% of overall daily calories. All other carbohydrates such as breads, rice, quinoa, pasta, sugary fruits and desserts or pastries all need to be eliminated from the daily diet to ensure the body remains in ketosis.
There are several versions of the ketogenic diet, including:
However, only the standard and high protein ketogenic diets have been studied extensively. Cyclical or targeted ketogenic diets are more advanced methods and primarily used by bodybuilders or athletes. [Retrieved from: Healthline.com]
The ketogenic diet can be very effective, but some precautions should be taken. One thing to remember is that since it takes two to three weeks to enter ketosis, the initial results are water weight lost. Depending on the person, fat loss may not be felt until anywhere from 2-4 weeks. So people beginning the ketogenic diet should be aware of these considerations. Another thing to be aware of is the long term weight loss effects on a ketogenic diet versus a higher carbohydrate diet have not been extensively studied. With the main principle of weight loss success being calories consumed in relation to calories burned, it is hard to quantify whether the ketogenic diet is any more effective than other diets that restrict calories or food intake. The long term effects of following a ketogenic diet have also not been studied to great length. Keeping the body in a ketogenic state for a long amount of time may lead to greater stress on other systems, such as the heart or liver, pancreas, or others. The level of saturated fat content in a standard ketogenic diet may also not be optimal for health. Due to the highly restrictive nature of the diet, it also can be hard for people to adhere to the low carbohydrate requirements long term [Retrieved from mayoclinic.com].
The ketogenic diet has many benefits and many supporters of the diet plan have experienced positive results. But just like any diet plan, it is recommended that people research and study all the positives and negatives before deciding to try the diet to decide if it is the right option. We also recommend always talking to a doctor before starting a diet plan, especially one that is as restrictive as the ketogenic diet.