Eating large amounts of meat from pigs, cows, goats or sheep increases the risk of death from cardiovascular disease and certain cancers, by about 30%.
Raising livestock also accounts for around 18% of greenhouse gases. It is therefore possible to act against climate change and reduce cardiovascular and cancer deaths, by cutting the production and consumption of ‘red meat’ from these animals. The World Cancer Research Fund and the American Institute for Cancer Research have recommended that an individual should eat no more than 500 grams of red meat per week.
Cardiovascular disease and cancer are two human diseases caused by similar factors influencing climate change. Others are the infectious disease influenza and salmonella, which are also related to animal elevation (zoonoses). Further examples not specifically related to agriculture, are respiratory diseases resulting from the burning of fossil and other fuels for transport and heating.
A different group of diseases cannot be said to share the causes of global warming. Instead they are caused by, or exacerbated by global warming. Examples are thermal stress, accidental and intentional injuries, and malnutrition or famine, all of which are expected to occur more frequently as the planet warms up and the climate becomes less stable. Health care systems all over the world will have to adapt to these changes.
Human disease and global warming are therefore related in several ways, and the World Health Organization (WHO) as well as national medical associations, have adopted policies to take these interrelationships into account. In contrast, professional societies within cardiovascular medicine and research have not yet addressed the relationships of climate change to cardiovascular disease, but they should consider doing so for at least two reasons.
The first is the relationship already described: risk of cardiovascular disease can be reduced by interventions which also reduce the risk of climate change. For example recommendations could be given regarding the consumption of red meat such as those already made by oncology institutions.
The second is advocacy. Physicians and biomedical researchers have the training to understand the physics, chemistry and statistics used in the climatological research that has demonstrated the gravity of the climate problem. Sea levels were for example, at least 15 to 25 meters higher than they are now when the earth’s atmosphere last had the same CO2 capacity as now (about 387 parts per million) which was three million years ago. Atmospheric CO2 concentrations are currently rising at 2 ppm / year.
It is difficult for politicians in democratic countries to make the necessary changes in national and international policies for energy, transport, agriculture, urban planning, family planning, etc, without general public understanding of the issues. Physicians and scientists devoted to understanding, preventing and treating cardiovascular disease also have the ability to understand the climate issue. Most importantly, they have the authority to promote this understanding through private and public debate. Not least because they can make statements, backed up by science, demonstrating that reducing the risk of heart attack can also impact upon climate change.