Log2Lose: Incenting Weight Loss and Dietary Self-monitoring in Real-time to Improve Weight Management Among Adults With Obesity

This study involves an evaluation of whether providing small incentives weekly for dietary self-monitoring and/or weight loss improves short- and long-term weight loss. Participants can expect to be on study for 18 months.

In this two-site, randomized, single-masked, longitudinal 2x2 factorial study, called Log2Lose, adults with obesity from Madison, WI and Durham, NC will be offered a 78 week, evidence-based behavioral weight management program comprising an incentivized weight loss intervention for 26 weeks (Phase I), an incentivized weight loss maintenance intervention for 26 weeks (Phase II), and a non-incentivized weight maintenance intervention for 26 weeks (Phase III). Participants will be randomized in a 2x2 design to receive adjunctive incentives for either weekly weight loss or dietary self-monitoring, both, or neither. The investigators will assess the proportion of participants achieving clinically significant weight loss of greater than or equal to 5 percent at the end of each phase.

All participants will participate in an 18-month weight management program delivered via videoconference.

Eligibility Criteria:
Inclusion Criteria:

* BMI ≥30 kg/m2
* Desire to lose weight
* Agrees to attend outcome visits per protocol
* Available for class times
* Transportation and ability to attend in-person study visits at baseline (screening), 26, 52, and 78 weeks
* Able to stand for weight measurements without assistance
* Able to speak and read English
* Able to download and use the MyFitnessPal and Fitbit apps daily
* Possess smart phone with data and texting plan
* Have or willing to create a Gmail address
* Able to connect to a video conference call using a smartphone, tablet or computer with a webcam and microphone
* Score of at least 4 out of 6 on a validated cognitive screener

Exclusion Criteria:

* Weight \>380 lb
* Weight loss of at least 10 lbs in the month prior to screening
* Currently enrolled or enrolled in previous month in a clinical, research, or community program focusing on lifestyle change that could affect weight
* Current use of weight loss medication
* History of bariatric surgery or planning to have bariatric surgery in the study timeframe
* Residing in a nursing home or receiving home health care
* Impaired hearing
* Significant dementia, drug or alcohol misuse, or unstable psychiatric illness (e.g., schizophrenia, psychosis)
* Current treatment for cancer or being treated for cancer (besides basal cell carcinoma or squamous cell) in the last 6 months
* Use of insulin, sulfonylureas, or meglitinides due to increased risk for hypoglycemia
* Pregnant, breastfeeding, or planning to become pregnant within the study timeframe
* Diuretic medication doses higher than hydrochlorothiazide 25 mg daily, furosemide 40 mg daily, torsemide 20 mg daily, bumetanide 1 mg daily, or any use of metolazone; use of potassium-sparing diuretics is acceptable
* Chronic kidney disease at stage 4 or 5
* Unstable heart disease in the 6 months prior to screening
* Exertional chest pain
* History of ascites requiring paracentesis
* Pain, fainting or other conditions that prohibit mild/moderate exercise