Background Reaching young adults with health messages has been a documented challenge in public health. Public health researchers have initiated studies to assess how social media are changing health communication. In 2014, the Centers for Disease Control and Prevention (CDC) launched social media-based health education initiatives on Facebook to increase knowledge of breast health and breast cancer among women under age 45 and those at higher risk for developing the disease. The current study used digital analytics and metrics to describe the impact of these social media efforts on health communication. Methods Engagement rate was calculated by taking the average engagement rate for 574 posts published by the CDC Breast Cancer Facebook page in multiple categories, including CDC campaign specificity, content type, time of day, and year posted. Linear regression was used to model the effect of campaign content. Results Engagement rate (ER) was highest for content shared for the Know:BRCA campaign posts (ER=6.4), followed by the non-campaign related posts (ER=5.5), and the Bring Your Brave posts (ER=4.6). Overall engagement rate decreased from 2014–2016. Photos consistently produced the most significant engagement rate overall. Conclusions We found that users were more likely to click, share, comment, or like the content of the post that had photos. These data suggest that that branded, visual content is more effective in facilitating engagement. These findings will be used to adjust both free and paid social media efforts for the CDC Breast Cancer Facebook page.