The UN has declared 2021-2030 as the decade of ecosystem restoration, and identified trees in agricultural landscapes as a viable means of meeting sustainable development goals. This is due to the pivotal role of trees in climate change adaptation and mitigation. The human health benefits of such restoration in mitigating against heat-stress is poorly evidenced. Outdoor agricultural workers are among the worst affected by extreme heat exposure. In Tanzania, this workforce forms 70% of the working population, making heat exposure both a health and economic concern. The proposed study will be most comprehensive work to date, evaluating the role of trees in mitigating the health effects of extreme heat exposure on agricultural workers. We will work with local and international experts in medicine, epidemiology, forestry, climatology, agriculture, and anthropology, and build on our land restoration work in Tanzania which has championed local farmers to regenerate 9 million native trees. The research will start by understanding heat risk and local adaptation practices, and thereafter, evaluate how trees on croplands alter microclimates to potentially protect workers against chronic kidney disease, dehydration, and cardiovascular strain. The findings will be disseminated through bespoke education and training packages co-developed and co-delivered with local stakeholders.