A Retrospective Study on the Safety and Efficacy of a Ketogenic Feeding Tube Diet in the Treatment of Obesity

Abstract

Background: According to the US Department of Health and Human Services, 35.7% of adults and 17% of children in the USA are currently obese. With no American state having an obesity prevalence of = 30%, surgical interventions such as gastric restrictive or diversion bariatric operations are becoming increasingly necessary. Non-surgical therapies like very low calorie diets (VLCD) and low calorie diets (LCD) are limited in potency of nutritional ketosis because carbohydrate-free formulas are not palatable to the patient. The current study therefore sought to evaluate a physician-supervised, outpatient, 10- day ketogenic feeding tube diet as an option for overweight or obese patients using a carbohydrate-free mixture of protein, fats and micronutrients. Methods: This is a retrospective clinic chart review (n=218) of patients who underwent a medically supervised weight loss program using a feeding tube to induce and maintain a state of nutritional ketosis. After medical evaluation, a pediatric feeding tube was inserted through the nose under local anesthesia and a carbohydrate-free ketogenic mixture delivering approximately 600 to 800 kcal/day was administered continuously. Over a 24-month period, 218 patients were treated, and 177 were identified as having verifiable initial and final weights, serial blood chemistries, urinary ketone levels, and fat free mass (FFM) as measured by DEXA. Results: The mean age of patients was 44.7 years (range 20-70 years), 83.1% were female, 65% were Caucasian. The mean BMI was 31.8 kg/m² (SD=5.0); the mean duration of treatment was 8.7 days (range 2-13 days). There was a significant increase in urinary ketones (p<0.001). There was a significant reduction in total body weight of 4.9 kg (SD=2.0, p<0.001) and BMI of 1.95 kg/m² (SD=0.68, p<0.001). The procedure was tolerated well with little or no discomfort by 72.9%; 15.8% removed the feeding tube early due to discomfort or personal reasons; 3.4% did not tolerate the treatment and 6.8% had their feeding tube reinserted during the treatment. There were no serious complications. Conclusion: The ketogenic feeding tube diet induced nutritional ketosis and led to a clinically significant weight loss in the 10-day program. This approach may play a role in the treatment of obesity to initiate weight loss in lifestyle or medication programs, to break through weight loss plateaus, or for preoperative weight loss prior to bariatric surgery. It may also be a useful medical strategy for patients who do not qualify for or refuse bariatric surgery, but are significantly overweight and in need of medical intervention after failing lifestyle modifications. (No Trial Registration required)