The truth on ketogenic diets and weight loss
As a Registered Dietitian and someone who is involved in weight-class sports, I get asked a lot about the ketogenic diet. So here is a quick summary of my personal recommendations for following a ketogenic diet.
Where does the ketogenic diet even come from?
Ketosis is a metabolic adaptation to famine. When the body runs out of glycogen stores (the body needs carbohydrates to replenish loss), the body breaks down fat for fuel. Historically, fasting was observed as a method to decrease seizure in epileptic patients due to the possible benefits of high levels of ketones in the body. Today, doctors have implemented the ketogenic diet to manage childhood epilepsy, however, the ketogenic is followed for health reasons that go beyond reducing seizures.
What is the ketogenic diet?
The ketogenic diet consists of a high fat to low-carb ratio with a moderate consumption of protein, putting the body in a metabolic state of ketosis. Essentially a true ketogenic diet consists of 75%-90% calories from fat, 10% from protein, and 5% from carbs. A common mistake people make when following a ketogenic diet is eating too much protein. Protein is another source of fuel our body uses and can be converted into glucose during starvation. Therefore, by following these guidelines your body will burn fat instead of glucose from carbohydrates or protein and preserve muscle mass.
So, how does the ketogenic diet works in terms of weight loss?
Like I mentioned, ketogenic diets go beyond treating seizures. During ketosis your body dramatically burns more fat. Higher fat metabolism increases the production of molecules called ketones. Ketones are acidic molecules formed in the liver and released as an alternative source of fuel that the body accepts within a week of ketone production. During ketosis, studies have reported a reduction in appetite, possible improvement in insulin sensitivity and glycemic control, and weight loss. However, the evidence behind ketogenic diets is still very unclear. Here are some theories on why the ketogenic diet might work for weight loss.
● The high-fat content in meals helps produce satiety and decrease food cravings
● Decrease the production of hunger hormones ghrelin and increase insulin secretion
● Lowers blood glucose levels due to an increase in insulin secretion
● The composition of ketone bodies may have a direct role in reducing hunger
However, although these possible benefits may seem promising, more research over longer periods of time is needed to determine whether keto is harmful or helpful in terms of weight loss.
With all of that being said, here is my personal recommendation….
The keto diet is not for everyone. Typically, over the span of six months people may lose more weight by following a ketogenic diet. But after a year, weight loss with this diet can be achieved with diets that allow more carbohydrates. Plus, low-carbohydrate diets are a lot more challenging in terms of compliance and restrict nutrient-dense foods. It is recommended that people with a history of high cholesterol should avoid ketogenic diets because the diet is high in fats. In summary, weight loss with any dietary strategy is difficult when behavioral changes, social support, and physical activity is not taken into consideration; there is no one diet/lifestyle fits all. Adults that are interested in pursuing a ketogenic diet or very low carbohydrate diet for weight loss should consult with a Registered Dietitian to weigh the risk.