The Ketogenic Diet and Weight Loss

Written by Jemma Geldard (Clinical Nutritionist)

The ketogenic diet was initially developed in the 1920s to treat epilepsy, following the observation that fasting could help to control seizures. In the body’s fasting state, fat stores are metabolized and then oxidation of these fats results in the production of ketone bodies. The production and use of these ketone bodies to produce energy is known as ketosis. The ketogenic diet is specifically designed to mimic the body’s starvation state, by restricting carbohydrate intake to 20-50g per day and shifting the predominant caloric intake to fats. This allows the body to use fat stores for energy instead of glucose. Ketogenic diets have been shown to be successful, at least in the short to medium term, to assist in weight loss and help fight obesity.

One of the benefits of ketosis in relation to weight loss is that it increases satiety and produces less rebound hypoglycemia due to the higher intake of fat and protein. This leads to reduced hunger and subsequently, overall food intake. The limitation of added sugar and refined carbohydrates can improve glycemic control and cardiometabolic risk factors, as well as reducing medication requirements for those with type 1 and type 2 diabetes. One of the early symptoms of ketosis is lethargy (the first 4-5 days), however following this phase, patients often will report an increase in energy and improvement in mood.

With the restriction of carbohydrates, however, comes a low intake of fruits, vegetables and healthy whole grains, which contain valuable micronutrients, antioxidants and fiber. Fiber is beneficial for overall health and keeping the bowels in check, so a fiber supplement may be required to prevent constipation while on a ketogenic diet. Increasing fat in the diet can also lead to an overconsumption of dairy products and animal fats. These foods can be high in saturated fat and cholesterol, which can cause an increase in LDL cholesterol and triglycerides. Periodic lipid profile testing and guidance by nutritionist a may be necessary to monitor these levels.

In summary, low-carbohydrate diets, and specifically ketogenic diets, may induce rapid weight loss initially from a loss of water in the body, followed by a loss of fat tissue. Although this diet may induce weight loss, compliancy eventually becomes difficult to maintain due to extreme restriction of one macronutrient, and healthy carbohydrates such whole grains need to be introduced back into the diet gradually to reduce rebound weight gain. Prolonged ketogenic diets are not well studied, and for this reason it is recommended to limit the duration from 3 weeks to a couple of months to stimulate fat loss and support transition to a Mediterranean style diet. To find out if a ketogenic diet is right for you, book in to speak with one of our practitioners today.