Self-efficacy and autonomous motivation are associated with lower sugar-sweetened beverage consumption in low-income overweight and obese mothers of young children.

Sugar-sweetened beverage (SSB) consumption is strongly associated with obesity. Autonomous motivation and self-efficacy, key concepts of self-determination theory, may influence SSB consumption. Low-income mothers of young children experience disproportionate rates of obesity. Whether autonomous motivation and self-efficacy are associated with SSB consumption in low-income mothers of young children is unknown. This exploratory secondary data analysis explored whether autonomous motivation or self-efficacy were associated with SBB consumption using data from a lifestyle intervention for low-income, overweight or obese mothers with young children. Participants (N = 311) completed surveys assessing autonomous motivation, self-efficacy, and SSB consumption at baseline, after the 16-week intervention, and at 3-month follow-up. Using baseline data, we performed linear regression models to explore associations of self-efficacy and autonomous motivation with SSB consumption. We also performed mixed effects models to explore whether autonomous motivation or self-efficacy were associated with SSB consumption over time. At baseline, a one-point increase in autonomous motivation and self-efficacy were associated with 4.36 (p < 0.001) and 6.43 (p = 0.025) fewer ounces of SSB consumption per day, respectively. In longitudinal models, SSB consumption decreased over time. Change in SSB consumption was associated with self-efficacy (B = -4.88; p = 0.015) and autonomous motivation (B = -2.29; p = 0.008). Our findings suggest self-efficacy and autonomous motivation may influence SSB consumption among mothers of young children with overweight and obesity. Further investigation should explore if self-efficacy and autonomous motivation have long-term effects on SSB consumption.