When people think about health, they generally think about things individuals can do to ward off disease — seeing a doctor, taking medicine, or dieting.

But increasingly, many health experts think this mindset needs to change. When we think about health, they say, we need to start thinking about how environmental factors can matter as much as — maybe even more than — any personal behaviors. And that includes big things like climate change:

In a big report released this summer, The Lancet brought together the world’s leading experts on environmental health. They argue that "[t]he implications of climate change for a global population of 9 billion people threatens to undermine the last half century of gains in development and global health":

The direct effects of climate change include increased heat stress, floods, drought, and increased frequency of intense storms, with the indirect threatening population health through adverse changes in air pollution, the spread of disease vectors, food insecurity and under-nutrition, displacement, and mental ill health.

Over the next five years, the authors urge governments to pay more attention to the health implications of climate change. That includes steps like:

Investing in climate change research and surveillance to better understand how the environment is affecting population health

Phasing out coal as a source of energy in order to protect people's cardiovascular and respiratory health

Redesigning cities to promote healthier lifestyles

The authors argue that "tackling climate change could be the greatest global health opportunity of the 21st century."

The health community has been reframing climate change as a health issue

This report doesn't come in isolation. The health community is increasingly trying to reframe climate change and other environmental problems as health issues.

The World Health Organization, in particular, has long been framing global warming as a health issue. "The evidence is overwhelming: Climate change endangers human health," said WHO Director General Margaret Chan. "Solutions exist, and we need to act decisively to change this trajectory."



The WHO has been collaborating with the UN's development program on pilot studies to boost the capacity of countries' health systems so they can adapt to climate change. These pilots look at how countries can better deal with everything from extreme heat events and air pollution to changing patterns of infectious disease.

Doctors are following suit. A recent study by the American Thoracic Society that focused on climate change found that seven in 10 doctors reported that climate change was contributing to more health problems among their patients. This included increases in allergic symptoms from plants or mold, severe weather injuries, and chronic disease severity caused by air pollution.

It's not just climate change, either. Every year, more than 7 million deaths are caused by air pollution — making it the second leading cause of preventable death after tobacco. According to WHO Director of Public Health and the Environment Maria Neira, "If we can address all the environmental health risk factors, we could reduce the global burden of disease by 25 percent."

The trouble is addressing the problem will require sectors other than health — such as transport, energy, agriculture — to wake up. They'll need to work with the health sector on actions that mitigate the health effects of climate change. And as long as climate change isn't seen as an urgent health issue, such action will be slow or nonexistent. Right now this isn't a widespread view: Research suggests few Americans think about climate change as a health issue.