AzTrials
AzTrials

Overweight and ObesityNCT04165707

A Weight Loss RCT Comparing Keyto vs Weight Watchers

A study testing Keyto device + app and Weight Watchers app in people with Overweight and Obesity and Ketogenic Diet, run by University of British Columbia at 1 site in Canada.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
Search all trials

Trial 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… Read more about this study

Who is it for?
Ages 18 to 64 years
Conditions the study is for
Overweight and Obesity, Ketogenic Diet
What is being tested?
Keyto device + app and Weight Watchers app
Type of treatment
Medical device
Could I receive a placebo?
No, everyone receives an active treatment
How many people
155 participants
Where
1 siteCanada
Study dates
9 Dec 2019to 11 Aug 2021
Phase
Interventional
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 64 years
  • All sexes
  • No healthy volunteers
  • Adult

Who may be able to join

  • 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
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  • 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

Who cannot join

  • 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
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  • 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
  • Experience with a low-carbohydrate of ketogenic diet within past 6 months

Trial locations and contacts

1 site in 1 country.

Canada1 site

  • University of British Columbia

    Kelowna, British Columbia, V1V 1V7

Other trials in Canada

About this study

Official title: A Randomized Controlled Trial Comparing Weight Loss Effects Between the Keyto Virtual "Ketogenic Diet" Program Compared to a Standard-care Weight Loss App

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.

Being tested
Keyto device + app, Weight Watchers app
Keywords
diet, weight loss, ketogenic diet, low carbohydrate
Medical subject headings
Overweight, Obesity, Weight Loss

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Keyto device + appDevice

    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.

  • Weight Watchers appOther

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

Study groups in NCT04165707
Study groupRoleWhat they receive
Keyto intervention armExperimentalKeyto device + app
Receives: Device: Keyto device + app
Weight Watchers comparator armActive comparatorWeight Watchers app
Receives: Other: Weight Watchers app

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Change in body mass at 12 weeks

    Change in body mass (in kilograms)

    Measured: 12 weeks from baseline

Secondary outcomes (18)

  1. Change in body mass at 24 and 48 weeks

    Change in body mass (in kilograms)

    Measured: 24 and 48 weeks from baseline

  2. Carbohydrate intake

    Total consumption of carbohydrates in 24 hour period (in grams)

    Measured: 12, 24, and 48 weeks from baseline

  3. Total fat intake

    Total consumption of fat in 24 hour period (in grams)

    Measured: 12, 24, and 48 weeks from baseline

  4. Saturated fat intake

    Total consumption of saturated fat in 24 hour period (in grams)

    Measured: 12, 24, and 48 weeks from baseline

  5. Polyunsaturated fat intake

    Total consumption of polyunsaturated fat in 24 hour period (in grams)

    Measured: 12, 24, and 48 weeks from baseline

  6. Monounsaturated fat intake

    Total consumption of monounsaturated fat in 24 hour period (in grams)

    Measured: 12, 24, and 48 weeks from baseline

  7. Total energy intake

    Total energy intake in 24 hour period (in kilocalories)

    Measured: 12, 24, and 48 weeks from baseline

  8. HbA1C

    Blood test will be used to determine changes in HbA1C

    Measured: 12 and 48 weeks from baseline

  9. Fasting glucose

    Blood test will be used to determine changes in fasting serum glucose

    Measured: 12 and 48 weeks from baseline

  10. Fasting insulin

    Blood test will be used to determine changes in fasting serum insulin

    Measured: 12 and 48 weeks from baseline

  11. Fasting high-sensitivity C-reactive protein

    Blood test will be used to determine changes in fasting serum high-sensitivity C-reactive protein

    Measured: 12 and 48 weeks from baseline

  12. Fasting homeostasis model assessment of insulin resistance (HOMA-IR)

    Blood test will be used to determine changes in HOMA-IR

    Measured: 12 and 48 weeks from baseline

  13. Fasting total cholesterol

    Blood test will be used to determine changes in serum total cholesterol

    Measured: 12 and 48 weeks from baseline

  14. Fasting high-density lipoprotein (HDL) cholesterol

    Blood test will be used to determine changes in serum HDL cholesterol

    Measured: 12 and 48 weeks from baseline

  15. Fasting lipoprotein fractions

    Blood test will determine changes in serum lipoprotein fractions measured by ion mobility

    Measured: 12 and 48 weeks from baseline

  16. Fasting lipoprotein (a)

    Blood test will determine changes in serum lipoprotein (a)

    Measured: 12 and 48 weeks from baseline

  17. Fasting triglycerides

    Blood test will determine changes in serum trigylcerides

    Measured: 12 and 48 weeks from baseline

  18. Fasting non-HDL cholesterol

    Blood test will determine changes in serum non-HDL cholesterol

    Measured: 12 and 48 weeks from baseline

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted18 Nov 2019
  2. Study start9 Dec 2019
  3. Primary completion2 Jan 2021
  4. Study completion11 Aug 2021

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Treatment
Allocation
Randomised
Intervention model
Parallel groups
Masking
None (open label)
Enrolment
155 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT04165707
Sponsor's protocol ID
H19-01341
Status last verified
Aug 2021
First submitted
6 Nov 2019
Last updated
26 Aug 2021
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No

Publications

  • 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.

    PubMed 41356752

  • 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.

    PubMed 38375882

  • 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.

    PubMed 35285809

  • 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.

    PubMed 32804087

Questions about this trial

What is this clinical trial studying?

A study testing Keyto device + app and Weight Watchers app in people with Overweight and Obesity and Ketogenic Diet, run by University of British Columbia at 1 site in Canada.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 13 inclusion and 16 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 26 Aug 2021. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Change in body mass at 12 weeks (time frame: 12 weeks from baseline). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT04165707, which also lists 4 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 26 Aug 2021.

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