Reduction of Internalized Weight Bias via Mindful Self-compassion: Theoretical Framework and Results from a Randomized Controlled Trial

Weight bias internalization is considered a chronic discriminatory stressor and a threat to health. Weight bias internalization has known associations with health-depleting behaviors (i.e., disordered eating, social isolation) and avoidance of health-promoting behaviors (i.e., physical activity, adherence to healthcare guidelines). Despite the numerous deleterious health effects of weight bias internalization, relatively few efficacious interventions have been identified for this critical treatment target. Self-compassion training presents itself as a potential intervention, though has not been rigorously tested in those with elevated internalized weight bias. Ruby was a two-arm randomized control designed to reduce internalized weight bias. Ruby tested the efficacy of a 4-week digitally-delivered self-compassion intervention compared to wait list control. Participants in the intervention group received daily text messages which included psychoeducation videos, writing prompts, and guided mindfulness audio files to facilitate daily mindful self-compassion practices ranging from 4-21 minutes per day. The main outcome of this trial was the 4-week reduction in weight bias internalization as measured by the Weight Bias Internalization Scale, compared to wait list control. Trial outcomes were analyzed using linear mixed models and one-way analysis of covariance models using an intent-to-treat framework. Ruby participants were 121 adults with elevated internalized weight bias (i.e., WBIS score > 4.0) and a body mass index over 30 kg/m2. Participants in the intervention demonstrated greater reductions in weight bias internalization compared to the wait list control (Net difference: -0.84, CI: -1.21 to -0.48, p < .0001). Participants in the intervention demonstrated similar reductions in secondary outcomes, including weight self-stigma, weight-related experiential avoidance, and fear of self-compassion (p’s < .05). Additionally, they reported increases in self-compassion, mindfulness, body appreciation, intuitive eating, and physical activity. Mediation analyses suggest that reductions in weight bias internalization are likely partially driven by increases in self-compassion. Ruby was the first digital standalone self-compassion based intervention targeting weight bias internalization. Results suggest that a brief mindful self-compassion intervention can meaningfully reduce internalized weight bias over 4 weeks. Additionally, a mindful self-compassion intervention can reduce several other secondary outcomes related to internalized weight bias. Due to its standalone digital delivery, Ruby may be a highly-scalable treatment for internalized weight bias that can be delivered on its own or combined with other treatments. Ruby is poised to expand a burgeoning body of literature related to psychological intervention for internalized weight bias.