A ketogenic diet is an excessively high intake of fats and an excessively low intake of carbohydrates. The body goes into starvation mode, where stored carbohydrates are no longer the fuel source, and ketone bodies (fatty acids) are. Ketone bodies are produced by the liver and used as a source of energy when glucose is not available. Small amounts of ketones are not necessarily harmful to the body, however it is still a restricted diet.
The diet leads you to pick from a small circle of foods. Heavily saturated meats, fish, eggs, oils, small amounts of nuts, avocados, cheese, heavy whipping cream, sour cream, butter, and puts a limit on what vegetables are “allowed.” The foods I have listed are foods that are typically high in saturated fats. A diet high in saturated fats puts you at risk for raising your “bad” cholesterol, which can eventually turn into heart disease.
This diet has become extremely popular as a means for quick weight loss and for body recomposition, however this diet gets abused. Sure, a burger (without the bun) cooked in the bacon grease that is on top of your burger, covered in a runny egg yolk, topped with mayonnaise, cheese, avocado sounds amazing. Where are the vitamins and minerals? There are some, but this burger could become more nutritionally complete by adding more vegetables. Oh, but you can’t add them because you had too many nuts earlier in the day and have reached your carbohydrate limit that puts you at risk for getting out of ketosis. This is diet restriction! A diet that limits you to plant consumption, is a diet that you should immediately reconsider.
Carbohydrates are not to be feared. In a 6-week trial by Johnston et al, they compared 2 different diets, a ketogenic very low carbohydrate diet and a non-ketogenic low carbohydrate diet. 20 adults participated with a BMI of 33.4 or above who were randomly assigned a diet with strict control over consumption everyday. After the 6 week period, they concluded that both diets were equally effective in reducing body weight and insulin resistance, however the ketogenic very low carbohydrate diet was associated with adverse metabolic and emotional effects.
There are people who have had success with this diet, but long-term sustainability is highly unlikely. Short-term, I have seen success with this diet for the obese population, however our bodies were made to digest and utilize carbohydrates. The moment carbohydrates are reintroduced to the body, overconsumption is almost inevitable. The more we restrict, the stronger the desire, it’s human nature.
My advice, don’t jump on the diet bandwagon for a quick fix. Create a lifestyle diet that doesn’t make you feel like you can’t have a particular food group. Long-term, you will be more successful including foods you want and crave in moderation as long as you can be patient with your weight loss endeavors. I do not have any intention of swaying you from exploring diet options and my opinion is based on my experience and research.
Johnston CS, Tjonn SL, Swan PD, White A, Hutchins H, Sears B. Ketogenic low-carbohydrate diets have no metabolic advantage over nonketogenic low-carbohydrate diets. Am J Clin Nutr 2006;83:1055–61