23andMe aims to recruit 91,227 adults to participate in a web-based weight loss intervention. Primary aims include: a.) to confirm whether AG/GG individuals at MTIF3 rs1885988 lose more weight on lifestyle interventions; and b.) to test the performance of a randomized controlled trial vs. self-selection study design in terms of weight loss, drop-outs, and adherence. Secondary (exploratory) analyses will focus on discovery of genetic and non-genetic predictors of weight loss success overall, and examination of potential interactions by intervention type. Web-administered intervention content, videos, and forums will be surfaced to participants every two weeks, and self-reported surveys will be surfaced weekly for the active intervention duration.
