BACKGROUND: Climate change has been recognized as both one of the biggest threats and the biggest opportunities for global health in the 21st century. This trend review seeks to assess and characterize the amount and type of scientific literature on the link between climate change and human health. DESIGN: We tracked the use of climate-related terms and their co-occurrence with health terms during the 25 years since the first Intergovernmental Panel on Climate Change (IPCC) report, from 1990 to 2014, in two scientific databases and in the IPCC reports. We investigated the trends in the number of publications about health and climate change through time, by nature of the health impact under study, and by geographic area. We compared the scientific production in the health field with that of other sectors on which climate change has an impact. RESULTS: The number of publications was extremely low in both databases from 1990 (325 and 1,004, respectively) until around 2006 (1,332 and 4,319, respectively), which has since then increased exponentially in recent years (6,079 and 17,395, respectively, in 2014). However, the number of climate change papers regarding health is still about half that of other sectors. Certain health impacts, particularly malnutrition and non-communicable diseases (NCDs), remain substantially understudied. Approximately two-thirds of all published studies were carried out in OECD countries (Organization for Economic Cooperation and Development), predominantly in Europe and North America. CONCLUSIONS: There is a clear need for further research on the links between climate change and health. This pertains particularly to research in and by those countries in which health will be mostly affected and capacity to adapt is least. Specific undertreated topics such as NCDs, malnutrition, and mental health should gain the priority they deserve. Funding agencies are invited to take note of and establish calls for proposals accordingly. Raising the interest in this research area in young scientists remains a challenge and should lead to innovative courses for large audiences, such as Massive Open Online Courses.