Background: Research suggests there is insufficient good quality information regarding the effectiveness of health education aimed at adults with intellectual disabilities. By analysing the literature, this review aimed to identify what constituted effectiveness in this context. Method: Relevant evaluations were extracted from bibliographic databases according to pre-specified criteria. Papers were analysed using QSR NVivo 11 by developing a narrative synthesis and analytic framework that identified and explored text addressing the research question. Results: Twenty-two studies were included. The review identified two broad components of effective health education: mechanisms and context. Mechanisms included embedded programme flexibility, appropriate and accessible resources, and motivational delivery. An effective context included an accessible and supportive environment and longer term opportunities for reinforcement of learning. Conclusions: Important gaps in the literature highlighted a need for further research addressing community learning experiences of adults with intellectual disabilities as well as the effectiveness of infection prevention programmes.