By Rachel Wyman
Clinical Nutrition Educator
The “keto” diet has seen a spike in interest over the past couple of months according to Google trends. This weight-loss fad was not originally designed for weight loss though, and it is not new. The ketogenic diet was created in 1921 at the Mayo Clinic by Dr. Russell Wilder as a treatment for severe intractable pediatric epilepsy in children. To this day, children and adults unresponsive to medication management see benefits to this protocol; approximately 50-60 percent experience a 50 percent or better seizure reduction, and one-third see a 90 percent or better seizure reduction.
What foods are consumed on a keto diet?
On a ketogenic diet, as with fasting, glucose reserves from the liver and muscles are depleted, triggering the liver to produce ketone bodies, which are then used by the central nervous system and body tissues as a fuel source. The ketogenic diet includes 75-80 percent calories from fat, 15-20 percent calories from protein and 5 percent or less calories from carbohydrate.
The diet targets no more than 20-50 grams of total carbohydrates per day. Included are meat, poultry, fish, shellfish, eggs, most types of cheese, oils, butter, cream, mayonnaise and limited amounts of nuts and certain nonstarchy vegetables. Excluded are grains, fruit, starchy vegetables, legumes and most dairy products. An example of a typical day might be: eggs cooked in oil with half an avocado for breakfast; arugula with sardines and oil for lunch; and skin-on chicken and cauliflower mashed with cream, butter and oil for dinner.
Is the keto diet effective?
While patients following a ketogenic diet often see fast rates of weight loss in the short term, a large bulk of this weight loss is water loss. A 2013 meta-analysis of randomized controlled trials comparing long-term weight loss in patients following ketogenic diets versus low-fat diets revealed a statistically significant but clinically minimal difference: an average weight loss of 2 pounds more over a 12-month timeframe in ketogenic diet followers.
Nutritional shortfalls include insufficient dietary fiber, suboptimal vitamins and minerals including vitamin C, potassium, magnesium and calcium, and generally low phytonutrient and antioxidant provision. For these reasons, the ketogenic diet as originally designed for seizure treatment typically involves a medical monitoring protocol including dietitian visits every 3 months along with laboratory studies including complete blood count, comprehensive metabolic panel and fasting lipid panel – all things that the average layperson does not usually access.
Is the keto diet safe?
Individuals with insulin-dependent diabetes, kidney failure, liver failure, or who are pregnant or lactating are often cautioned against this approach. Adverse effects may include constipation, nausea, vomiting, “brain fog,” fatigue, headaches, electrolyte imbalances, kidney stones, bone fractures and potential loss of muscle mass.
Ultimately, any diet that limits food variety can suppress appetite and result in decreased calorie intake. To date, there is still uncertainty regarding the impact of following a long-term ketogenic diet on quality of life, health and longevity of humans.
When evaluating methods of weight loss, it is important to find a method that incorporates lifestyle changes that one can adhere to safely and confidently for the rest of their life, even once weight loss is achieved, otherwise weight regain will follow and potentially other health challenges.
Rachel Wyman, RD, is a Clinical Nutrition Educator at Mission Weight Management.
References: Bueno, N. B., Melo, I. S., Oliveira, S. L., & Ataide, T. D. (2013). Very-low-carbohydrate ketogenic diet v. low-fat diet for long-term weight loss: a meta-analysis of randomised controlled trials. British Journal of Nutrition, 110(07), 1178-1187. doi:10.1017/s0007114513000548; Kossoff, E., & Wang, H. (2013). Dietary Therapies for Epilepsy. Biomedical Journal, 36(1), 2-8. doi:10.4103/2319-4170.107152; Yang, M. U., & Itallie, T. B. (1976). Composition of weight lost during short-term weight reduction. Metabolic responses of obese subjects to starvation and low-calorie ketogenic and nonketogenic diets. Journal of Clinical Investigation, 58(3), 722-730. doi:10.1172/jci108519