The prevalence of various health problems in Nigeria and their devastating consequences on the socio-economic status of the nation is such that seems to have defied all logics. The Nigerian government at various levels and many international health and funding agencies continue to make efforts to improve the health status of the individual members of Nigerian society and the health sector at large. However, scholars have continued to identify and emphasise the strategic position and the need to use the media as a complementary approach to advance the health sector and to achieve good health outcomes among members of society. This study, therefore, examines the coverage of health issues by Nigerian newspapers, emphasising the degree of attention given to HIV/AIDS, malaria, polio and the northern region. The study further examines the relationship between dissemination of health information by Nigerian newspapers and the health behaviours of newspaper readers and the challenges being encountered by health reporters in the field of health reporting in Nigeria. With a comprehensive literature review underpinning priming and framing within the framework of agenda setting theory; and a triangular methodological approach of content analysis of 844 editions of four national newspapers from 2010-2013, survey and in-depth interviews, the study finds a moderate coverage of HIV/AIDS, malaria, polio in Nigerian newspapers in relation to other diseases studied. These three diseases are also reported in relation to northern Nigeria more than other regions included in this study. But in general, Nigerian newspapers have not given prominent coverage to health issues in their leads, editorials and other important pages. This finding suggests that Nigerian newspapers appear to give prominent attention to other issues which, as noted by health reporters interviewed, include politics and economy, over health issues. Given that Nigerian newspapers have not given prominent coverage to health issues, this suggests that Nigerian newspapers may have less influence in directing the attention of the Nigerian government towards making health a top priority in the government agenda. The study also shows that dissemination of health information by Nigerian newspapers correlates with an improvement in the health behaviours of newspaper readers in the country. Furthermore, interviewed 13 newspapers health reporters across the national newspapers in Nigeria and find that health reporters generally face a wide range of challenges due to the specialised and technical nature of health reporting. Health reporters who were trained in health and sciences demonstrate better expertise and skills in health reporting in Nigeria than health reporters who were trained in the arts and social sciences. This finding suggests that health and science training has a major influence in health reporting in Nigeria. The finding may further imply that health and science background may be considered important in employing health reporters for the field of health reporting given the technical nature and some degree of health and science expertise required for optimal job performance in the field.