Comparing the Keyto App and Device with Weight Watchers’ WW App for Weight Loss: Protocol for a Randomized Trial

Abstract

Background Obesity and being overweight are major contributing factors for many diseases. Calorie restricted diets often fail to result in sustained long-term weight loss. Very low–carbohydrate, high-fat ketogenic diets have been suggested to have superior metabolic and weight loss effects. Keyto is a low-cost, highly scalable mobile health (mHealth) app paired with a noninvasive biofeedback tool aimed at facilitating weight loss through a personalized healthy and predominantly plant- and fish-based ketogenic diet. Objective This protocol describes a randomized trial comparing the efficacy of the Keyto mHealth app and device intervention to that of Weight Watchers’ WW app in individuals who are overweight or obese. The primary outcome is weight loss after 12 weeks. Secondary and exploratory outcomes, including metabolic and cardiovascular risk factors, will be assessed at 12, 24, and 48 weeks. Methods A total of 144 participants will be recruited and randomized to either the Keyto program or Weight Watchers program. Study participants will be guided through the study via video conference or phone calls and will undergo a fasting blood analysis performed by a third-party diagnostic lab at weeks 0 and 12 to assess metabolic and cardiovascular risk markers. All participants will be asked to weigh themselves daily on a study-provided Bluetooth-enabled scale. Participants randomized to the Keyto arm will also be asked to measure their breath acetone levels, a measure of ketosis, with the Keyto device 3 times per day. Results Recruitment started in December 2019. Rolling recruitment is expected to be completed by July 2020. Data collection and analysis of the primary intervention phase is expected to be completed in October 2020. The 24- and 48-week follow-ups are expected to be completed in January 2021 and July 2021, respectively. Conclusions This trial will provide high-quality evidence regarding the efficacy of the Keyto weight loss program in individuals who are overweight and obese in a free-living condition. This study also fills a gap by examining the impact of a ketogenic diet emphasizing plant- and fish-based fats on blood lipid profile and cardiovascular disease risk. Trial Registration ClinicalTrials.gov NCT04165707; https://clinicaltrials.gov/ct2/show/NCT04165707. International Registered Report Identifier (IRRID) DERR1-10.2196/19053

Keyto app and device versus WW app on weight loss and metabolic risk in adults with overweight or obesity: A randomized trial

“…The study was conducted with approval from the University of British Columbia’s clinical research ethics board, and all participants provided written informed consent digitally prior to data collection. The clinical trial was registered on ClinicalTrials.gov (NCT04165707) and the protocol published (DERR1‐10.2196/19053) ( 9 ).…”

“…A total of 155 participants with overweight/obesity (BMI 27 to 43 kg/m 2 ) from the state of California were recruited between December 1, 2019, and August 11, 2020, and randomized to one of the interventions. Key exclusion criteria were pregnancy, current smoker, diabetes diagnosis, history of heart attack, bariatric surgery, eating disorder, losing or gaining more than 5% body weight in past 6 months, and currently following a low‐carbohydrate or ketogenic diet ( 9 ). The original published protocol aimed to recruit 144 participants per the a priori sample size calculation in order to detect a clinically meaningful 5% difference in weight loss with 80% power and α = 0.5 with two groups and two time points (baseline and primary outcome at 12 weeks), assuming a mean body mass of 100 kg with a standard deviation of 15 kg and a correlation among repeated measures of r = 0.75 ( 9 ).…”

“…Key exclusion criteria were pregnancy, current smoker, diabetes diagnosis, history of heart attack, bariatric surgery, eating disorder, losing or gaining more than 5% body weight in past 6 months, and currently following a low‐carbohydrate or ketogenic diet ( 9 ). The original published protocol aimed to recruit 144 participants per the a priori sample size calculation in order to detect a clinically meaningful 5% difference in weight loss with 80% power and α = 0.5 with two groups and two time points (baseline and primary outcome at 12 weeks), assuming a mean body mass of 100 kg with a standard deviation of 15 kg and a correlation among repeated measures of r = 0.75 ( 9 ). To account for an expected increase in dropout rate due to the challenges of the COVID‐19 pandemic, the trial steering committee decided to increase enrollment to 155 participants on July 28, 2020.…”

“…Furthermore, the app contains so‐called zero‐point low‐calorie foods that can be consumed ad libitum and that do not count toward the daily points allotment ( 12 ). Both apps provided similar ancillary resources, including recipes, a food search option, and a social support function, as detailed previously ( 9 ).…”

“…Data collected for this study, including individual deidentified participant data and a data dictionary defining each field in the set, will be made available to others with an academic affiliation upon reasonable request from the corresponding author. The published study protocol is available ( 9 ).…”