Danielle Dunnagan, MS, RD, CSSD, LD
Nutrition Care Division
Eisenhower Army Medical Center

It's no secret the ketogenic diet has gained public popularity over recent years and is a hot topic of conversation among military personnel. A quick "keto" internet search produces numerous health claims ranging from the final solution for weight loss to a possible therapy for several chronic diseases including diabetes, dementia and cancer.

Even the Navy SEALS have been associated with studies to determine if the high fat, very low carbohydrate diet may decrease risk for seizures during underwater missions. Given all the media rage, is keto everything it's advertised to be?

What is keto?
Surprisingly, the classical ketogenic diet is not a new discovery to the medical community. According to the Academy of Nutrition and Dietetics, ketogenic diets have been used to help control seizures in children with epilepsy since the 1920s. A typical ketogenic diet is 80-90 percent fat, 6-15 percent protein, and carbohydrate intake that is restricted to less than 5-10 percent of total calories. In practical terms, an example of breakfast is mostly eggs, cream, butter, and cheese with a very small portion of fruit and vegetables. This high fat diet forces the body and brain to use ketones (a byproduct of fat breakdown) for fuel instead of glucose which is referred to as ketosis.

Is it easy to follow?
The diet seems simple enough; however adherence is difficult and one must consistently monitor blood or urinary ketone levels to ensure ketosis is maintained. Eating too many grams of carbohydrates or protein and you are back to using carbohydrates (glucose) for energy. Many dietitians will agree that the popularized version of keto is not as comparable to the classical ketogenic diet used when attempting to control seizures.

Various commercialized keto recipes emphasize protein and vegetables and primarily limit carbohydrates. This more closely aligns with a modified Atkins Diet which may or may not result in ketosis. Regardless of the degree of restriction, staying consistent is imperative and can be difficult long term. Occasions such as holidays, social events or deployments are common reasons the diet is discontinued.

What does research say?
Current research is limited to support using the ketogenic diet for treatment of chronic illnesses such as obesity, diabetes and dementia. The Academy of Nutrition and Dietetics discourages individuals from following a ketogenic diet if pancreatic, liver, thyroid or gallbladder problems exist or if any history of an eating disorder is present. Further research is needed to determine short- and long-term effects of adhering to the diet. Nausea, dizziness, headache, and fatigue (known as "keto flu"), changes in bowel regularity, and difficulty sleeping are frequent complaints when beginning the diet. Long-term health risks include kidney stones, liver disease, and vitamin and mineral deficiencies.

Should the military use it?
Areas of interest for implementing the ketogenic diet among military personnel are also ongoing. A recent study published in Military Medicine concluded that "U.S. military personnel demonstrated high adherence to a ketogenic diet and showed remarkable weight loss … without compromising physical performance adaptations to exercise training."

Keto has also been a hot topic within U.S. Special Operations due to the diet's potential impact on increasing time Navy SEALS may be able to remain underwater and avoid seizures. Overall practicality of implementing the diet is still out for debate and not enough evidence exists to support using the ketogenic diet over current sports nutrition guidelines.

In conclusion, the ketogenic diet remains a method of treatment for epilepsy but more research is needed before applying the diet in other clinical and performance nutrition settings. Medical guidance is highly encouraged if you are interested in pursuing a ketogenic diet to ensure nutritional needs are met and ketosis is safely maintained.

Sources:
• Dennett, Carrie. "The Ketogenic Diet for Weight Loss -- Today's Dietitian Magazine." Today's Dietitian, Jan. 2019, www.todaysdietitian.com/newarchives/0119p26.shtml.
• Gordon, Barbara. "What Is the Ketogenic Diet." EatRight, 15 May 2019, www.eatright.org/health/weight-loss/fad-diets/what-is-the-ketogenic-diet.
• "Keto Diet Considered for Navy SEALS." News, The President and Fellows of Harvard College, 19 June 2019, www.hsph.harvard.edu/news/hsph-in-the-news/keto-diet-navy-seals/.
• "Ketogenic Diet and Performance Enhancement." HPRC, www.hprc-online.org/nutrition/performance-nutrition/ketogenic-diet-and-performance-enhancement.
• "Ketogenic Diet." Epilepsy Foundation, www.epilepsy.com/learn/treating-seizures-and-epilepsy/dietary-therapies/ketogenic.
• Roehl, Kelly, and Sarika L. Sewak. "Practice Paper of the Academy of Nutrition and Dietetics: Classic and Modified Ketogenic Diets for Treatment of Epilepsy." Journal of the Academy of Nutrition and Dietetics, vol. 117, no. 8, 2017, pp. 1279--1292., doi:10.1016/j.jand.2017.06.006.
• Volek, Jeff S, et al. "Extended Ketogenic Diet and Physical Training Intervention in Military Personnel." Military Medicine, 2019, doi:10.1093/milmed/usz184.