Bloggers can help stimulate online conversations among their readers about a variety of health topics, including breast cancer. However, in previous studies, researchers have not specifically examined supportive messages within an online blogger community that stem from an intervention where bloggers were provided with evidence-based information about breast cancer risk that they could tailor and disseminate to their readers. In the current study, we content analyzed 282 supportive messages within online conversations from participants in blogger communities over a 2-month period immediately following an intervention where the authors provided 74 bloggers who write about motherhood issues with an infographic based on evidence-based information from the Breast Cancer and the Environment Research Program (BCERP) about environmental breast cancer risk/prevention. Bloggers who shared information about their personal breast cancer risk generated a significantly higher number of blog reader comments than bloggers who did not share information about their personal breast cancer risk. Bloggers who cited breast cancer statistics in posts were more likely to draw esteem and emotional support from their readers. Bloggers' repetition of information from blog intervention messages was more likely to elicit esteem, informational, and emotional support from readers. Disclosure of a personal breast cancer diagnosis was associated with mixed types of social support messages. The theoretical and practical implications are discussed along with key limitations of the study and future directions for research in this area.