Objective: African Americans in the USA experience a disproportionate burden of chronic disease. Healthy lifestyle promotion programmes can help decrease this disease risk. This study determined the feasibility of using dyadic peer support to augment an existing healthy lifestyle programme in African American churches. Design: A prospective pre-post design was used with 80 participants from three churches in the southeastern USA over an 18-week period. Methods: Participants attended 9 weeks of group nutrition classes followed by 9 weeks of a dyadic peer support programme. Feasibility was measured by recruitment, acceptability, ability to collect peer support data, ability to implement the peer support component and preliminary health outcomes. Descriptive statistics and multilevel models were used to analyse the data. Results: Seventy-eight percent of participants completed group classes and peer support activities. Over 95% of participants would work with a partner again. Lay leaders and educators felt they had the resources and participant support to implement a dyadic peer support intervention. Participants achieved small but significant average increases of 1.1 fruit servings per day (p = 0.001) and 1.2 days of physical activity per week (p = 0.01) post-intervention. Significant changes in weight (-2.6 pounds, 95% confidence interval [CI] = -4.18, -1.1; p = 0.001) and vegetable intake (0.681 servings, 95% CI = 0.122, 1.241; p = 0.017) achieved during the first 9 weeks of the programme were maintained during the second 9 weeks. Conclusion: Dyadic peer support can successfully be used to augment existing healthy lifestyle promotion programmes within African American churches. Studies using control groups are needed to test the effectiveness of dyadic peer support on health outcomes more rigorously.