Cooking Interventions for Improving Diet Quality Among Black Americans: A Randomized Controlled Trial

Non-Hispanic Black Americans experience the highest, and most rapidly increasing, rates of obesity. Despite evidence that this is at least somewhat related to poor diet quality, we have yet to identify effective interventions for improving diet quality long-term. Restrictive diets can be ineffective and often harmful. In contrast, there is a well-established connection between home cooking and lower body mass index, better diet quality, and improved health.

The present study applied the Theory of Planned Behavior (TPB) to examine the effect of an intervention delivering cooking instruction, rather than nutrition information, on beliefs, attitudes, and behaviors pertaining to diet quality and cooking among Black adults in the USA.

An online sample of Black Americans (N = 147), ages 18-76 (M = 30.69, SD = 10.42) were recruited via Prolific and randomized to view either a cooking tutorial video or a "standard of care" control webpage followed by either an implementation intentions (II) writing activity or a "freestyle" control writing activity. Cognitions and behavior related to healthy eating and cooking were measured at baseline, post-intervention, and 1-week follow-up.

Results of mixed-effects modeling indicated that participants randomized to the video condition reported significantly greater post-intervention intentions to cook (p < .001), which positively correlated with cooking behavior over the subsequent week (p < .01). There was no effect of the II intervention on subsequent-week behavior (ps > .413). Importantly, 75% (n = 105) indicated experiencing food insecurity at the time of data collection.

These results highlight a promising pathway for improving nutrition and diet-related health outcomes among Black Americans while highlighting that any intervention must account for food insecurity in this population.