A Weight Loss RCT Comparing Keyto vs Weight Watchers

NCT04165707 | Completed

• 1 other identifier: H19-01341
• Study Type: interventional
• Target: 155
• Locations: 1 country
• Sites: 1

Brief Summary

Very low-carbohydrate ketogenic diet may have beneficial metabolic and weight loss effects, however, adhering to this diet may be challenging. Keyto is a self-monitoring and app-enhanced intervention to help individuals learn about and monitor their breath acetone (a measure of ketosis) levels to promote dietary change and weight loss. The purpose of this research is to test the Keyto self-monitoring + app intervention against a "standard of care" weight loss dietary app (Weight Watchers). 144 participants will be recruited through Facebook ads, provide online consent, and will be randomized to one of the two conditions. Weight loss after 12 weeks will be assessed as the primary outcome, with weight loss at 24 and 48 weeks being secondary outcomes. Blood samples will be collected at baseline and 12 weeks with optional blood samples at 48 weeks follow up.

Conditions

Overweight and Obesity; Ketogenic Diet

Keywords

diet; weight loss; ketogenic diet; low carbohydrate

Outcome Measures

Primary Outcomes (1)

• Change in body mass at 12 weeks

  Change in body mass (in kilograms)

  12 weeks from baseline

Secondary Outcomes (18)

• Change in body mass at 24 and 48 weeks

  24 and 48 weeks from baseline

• Carbohydrate intake

  12, 24, and 48 weeks from baseline

• Total fat intake

  12, 24, and 48 weeks from baseline

• Saturated fat intake

  12, 24, and 48 weeks from baseline

• Polyunsaturated fat intake

  12, 24, and 48 weeks from baseline

Other Outcomes (6)

• Fasting albumin

  12 and 48 weeks from baseline

• Fasting globulin

  12 and 48 weeks from baseline

• Fasting total bilirubin

  12 and 48 weeks from baseline

Study Arms (2)

Keyto intervention arm

EXPERIMENTAL

Keyto device + app

Device: Keyto device + app

Weight Watchers comparator arm

ACTIVE COMPARATOR

Weight Watchers app

Other: Weight Watchers app

Interventions

Keyto device + app DEVICE

Keyto is a self-monitoring and app-enhanced intervention to help individuals learn about and monitor their breath acetone (a measure of ketosis) levels to promote a very low carbohydrate diet and weight loss.

Keyto intervention arm

Weight Watchers app OTHER

The Weight Watchers app helps people to monitor their food intake, track points and provides recipe ideas to support weight loss.

Weight Watchers comparator arm

Eligibility Criteria

• Age: 18 Years - 64 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Age 18-64
• Living in the State of California
• Body mass index (BMI) 27-43
• Must speak, read, and comprehend English
• Access to reliable internet and wi-fi
• Must have a valid email address and phone number
• Must have an Apple iPhone (iPhone 7 or later, iOS 11 or later) with cellular data plan
• Must have a kitchen and be willing to cook
• Willingness to reduce carbohydrate intake to less than 30g/day
• Willingness to restrict intake of added sugar, bread, grain, rice, pasta, sweets, most fruits, pastries, and other carbohydrates
• Willingness to comply with a strict diet for 12 months
• Willingness to eat a diet that is primarily plant and fish-based
• Interest in losing weight

You may not qualify if:

• HIV or immunocompromised
• Current or past cancer diagnosis
• Pregnant, breastfeeding, or planned pregnancy in next 12 months
• Beginning or ending hormonal contraception in next 12 months
• Current diagnosis of diabetes
• History of heart attack or stent
• Currently taking glucose-lowering drugs, statins, or oral steroids
• History of gastric bypass surgery or any other weight-loss surgery
• History of anorexia or bulimia
• History of mental illness
• Current smoker or smoked cigarettes within past 12 months
• Currently eating fewer than 50 g carbohydrates per day
• Have tried a low-carb, high fat (ketogenic diet) within the past 3 months
• Recent weight loss or gain of more than 5% body weight in past 6 months
• Previous experience with the Weight Watchers diet app

Sponsors & Collaborators

• University of British Columbia: lead

Study Sites (1)

University of British Columbia

Kelowna, British Columbia, V1V 1V7, Canada

Location

Related Publications (4)

• Falkenhain K, Lowe DA, Locke SR, Singer J, Weiss EJ, Little JP. Long-Term Weight Loss in Adults With Overweight or Obesity Using a Breath Biofeedback mHealth App: A One-Year Follow-Up of a Randomized Trial. Obes Sci Pract. 2025 Dec 5;11(6):e70106. doi: 10.1002/osp4.70106. eCollection 2025 Dec.

  PMID: 41356752 DERIVED

• Metzendorf MI, Wieland LS, Richter B. Mobile health (m-health) smartphone interventions for adolescents and adults with overweight or obesity. Cochrane Database Syst Rev. 2024 Feb 20;2(2):CD013591. doi: 10.1002/14651858.CD013591.pub2.

  PMID: 38375882 DERIVED

• Falkenhain K, Locke SR, Lowe DA, Lee T, Singer J, Weiss EJ, Little JP. Use of an mHealth Ketogenic Diet App Intervention and User Behaviors Associated With Weight Loss in Adults With Overweight or Obesity: Secondary Analysis of a Randomized Clinical Trial. JMIR Mhealth Uhealth. 2022 Mar 14;10(3):e33940. doi: 10.2196/33940.

  PMID: 35285809 DERIVED

• Locke SR, Falkenhain K, Lowe DA, Lee T, Singer J, Weiss EJ, Little JP. Comparing the Keyto App and Device with Weight Watchers' WW App for Weight Loss: Protocol for a Randomized Trial. JMIR Res Protoc. 2020 Aug 17;9(8):e19053. doi: 10.2196/19053.

  PMID: 32804087 DERIVED

MeSH Terms

Conditions

Overweight; Obesity; Weight Loss

Condition Hierarchy (Ancestors)

Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Body Weight Changes

Study Officials

• Jonathan Little, PhD

  University of British Columbia

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Study Record Dates

• First Submitted: November 6, 2019
• First Posted: November 18, 2019
• Study Start: December 9, 2019
• Primary Completion: January 2, 2021
• Study Completion: August 11, 2021
• Last Updated: August 26, 2021

Record last verified: 2021-08

Locations

CA (1)