Last week, experts writing in medical journal the Lancet gave a worrying assessment of the possible impacts of climate change on health and nutrition.

The researchers, from academic institutes including Oxford University’s Martin Programme on the Future of Food and the International Food Policy Research Institute, said that most previous work has focused on the effects of climate change on the availability of food, whilst they looked at impacts of expected changes in agricultural production and dietary patterns.

They estimate that diet-related deaths will increase by over half a million by 2050, as a result of climate change, with India, China and countries in the Western Pacific worst affected. The number of deaths related to reduced fruit and vegetable availability (stemming from lower productivity in key crops) is expected to double by mid-century.

The breakdown of results show changes in fruit and vegetable intake are likely to be felt across high-income countries (accounting for 58% of all changes in deaths), in low- and middle-income countries (LMIC) of the Western Pacific (74%), Europe (60%), and the Eastern Mediterranean (42%). Southeast Asia and Africa top the list for underweight related-deaths in adults, accounting for 47% and 49% of all changes in deaths in 2050 respectively.

Dr Marco Springmann, who led the study with Oxford University’s Martin Programme, commented, “We found that in 2050, these changes could be responsible for around 529,000 extra deaths. We looked at the health effects of changes in agricultural production that are likely to result from climate change and found that even modest reductions in the availability of food per person could lead to changes in the energy content and composition of diets, and these changes will have major consequences for health.”

The projections were made through computer analysis, using the IMPACT agricultural modelling framework. Scientists looked at the predicted impacts across a range of possible climate scenarios and in 155 different countries. They said that policy action to reduce the projected impacts of climate change could reduce the number of predicted deaths by upwards of 350,000, potentially saving many lives if policies are stringent enough.

The researchers said the projected impacts of climate change on diet and health could be more damaging than other climate-related health impacts that have received more attention. They recommended “Strengthening of public health programmes aimed at preventing and treating diet and weight-related risk factors,” which could be considered climate-change adaptation strategies, given their findings. They also said work to drastically reduce climate changing emissions will be essential in order to avoid the worst possible impacts.

Dr Springmann added, “Climate change is likely to have a substantial negative impact on future mortality, even under optimistic scenarios. Adaptation efforts need to be scaled up rapidly. Public-health programmes aimed at preventing and treating diet and weight-related risk factors, such as increasing fruit and vegetable intake, must be strengthened as a matter of priority to help mitigate climate-related health effects.”

It has been estimated that food availability will increase this century. However, the study’s results show that, unless action is taken to reduce global emissions, projected improvements in this area could be slashed by about a third by 2050. What is more, the number of climate-related deaths is predicted to massively outstrip the projected health benefits of reduced red meat consumption - this is expected to prevent 29,000 deaths over the same time frame.

The paper is available here.