The Surprising Ways Climate Change Is Already Affecting Our Health

“So, I recognize the irony in this analogy,” begins Renee Salas, MD, MPH, an emergency medicine doctor and a fellow at the Center for Climate, Health, and the Global Environment at Harvard University. “But the effect climate change has on health is kind of like an iceberg. There are the connections research and science has shown us — that’s what’s above water. But there’s probably so much more going on underneath the surface.”

Even considering that, the effects we can see are  shocking. “In 2014, we did a survey of physicians at the National Medical Association [a U.S. organization representing African American physicians and their patients]. It found that 88% of our doctors were already seeing the health effects of climate change in their patients,” Mark Mitchell, MD, a public health physician specializing in environmental health, tells Refinery29.

The main thing these physicians reported was an exacerbation of preexisting heart and lung conditions, says Dr. Mitchell, who is also the associate professor of Climate Change, Energy, and Environmental Health Equity at George Mason University. But injuries from severe weather events, such as smoke inhalation due to wildfires, were equally common.

When I ask him to list all the ways we know climate change is harming health, he uses the mnemonic HEATWAVE, meaning: Heat effects; Exacerbation of preexisting heart and lung conditions; Asthma; Traumatic injury caused by climate-related severe weather; Water- and food-borne illnesses; Allergies; Vector-borne diseases, such as West Nile and Zika; and Emotional and mental health impacts from experiences like loss of property or life due to climate-related disaster.

Many of these problems are either partially or exclusively driven by the fact that the world is getting hotter. So if climate change is the iceberg, then its tip consists of the problems we can see, like the risk of heat-related illness and death. 

But lurking below the surface are dozens of less-obvious but profound dangers. Like this: Rising heat is associated with an increased incidence in antibiotics-resistant bacteria, Dr. Salas tells Refinery29. Or this: When pregnant women are exposed to extreme temperature, their fetuses may be at an increased risk of congenital heart defects. 

Climate change may also be contributing to the spread of disease-carrying insects like ticks into new areas, resulting in an increase of issues like Lyme disease. Heat may play a role in hastening the spread of viruses like West Nile and Zika, too, by altering mosquitoes' lifespan and behavior.

Increasing heat increases air pollution and lengthens the ragweed pollen season, which in turn exacerbates allergies and asthma, Dr. Mitchell points out: “Some of our allergists in the NMA are saying that they are concerned that they’re having to provide more and more adult allergy medications to younger and younger children — even though many haven’t been approved for kids. But the health effects are getting worse faster than we’re doing the research required to find out which medications are safe in kids.”

Then there’s the fact that students in non-air-conditioned buildings have a hard time thinking; they can fall behind in school. Heat can impair sleep among those who do not have access to air conditioners, which can have widespread impacts on their life. “That can be a hidden way it harms health,” Dr. Salas says. “Heat is insidious.”

So too are extreme weather conditions and climate-related disasters, both of which have become more common in the past several years due to climate change. Hurricanes, flooding, wildfires, and drought all have the power to kill and injure, as we’re seeing in real time with the West Coast wildfires, which have killed at least 33 people and affected countless others through issues like smoke inhalation.

But a less-talked-about way climate change affects health is by damaging infrastructure, Dr. Salas notes. Power outages are becoming more frequent due to heat and extreme weather events, she says. “In one case, the hospital down the street from where I live lost power,” she tells me, explaining that the building had generators, but only enough to cool certain areas. “They had to evacuate patients from the upper levels because it got so hot. Even once the power was restored, some of the equipment had gotten so hot that it took even longer for it to come back online.” After Hurricane Maria, she adds, a factory in Puerto Rico that made hospital equipment was damaged; shortages reached Dr. Salas’s hospital in Boston: “We had strict criteria on who could receive IV fluids, and I handed out Gatorade to those who didn't meet the criteria.”

Some of the damage is more subtle. While many areas aren’t necessarily getting more precipitation annually, the U.S. is experiencing more heavy downpours, Dr. Mitchell says. As a result, buildings, especially sub-standard housing, are developing more leaks, and the increased moisture is allowing more mold to grow — and that can worsen asthma and allergies.

Then there are the mental health effects of climate change, which Surili Patel, the director of the Center for Climate, Health and Equity, says get underreported. “There are acute impacts, such as the post-traumatic stress disorder after a hurricane rips through a town, but there are gradual impacts too,” she explains. “When a kid has grown up with the possibility of a severe asthma attack hanging over their head, that is harmful to mental health.”

Not all communities are equally impacted by the health-related effects of climate change. The experts who spoke with Refinery29 said the young, the elderly, the low-income, and communities of color are particularly vulnerable.

Children and the elderly (and, Dr. Mitchell adds, pregnant people) are especially at risk physically. Children’s bodies are still developing, which makes them more susceptible to illness from increased air and water pollution. Their mental health may also be harmed long-term by climate-related disaster disruptions and displacements from their home lives.

Older adults are predisposed to health conditions and prone to injury, Patel notes. They’re also less able to regulate their body temperature, making them at high risk for issues like heat stroke.

Pregnant women are more likely to become dehydrated, always a risk in extreme heat. “They can even go into premature labor due to heat,” Dr. Mitchell notes. Premature babies are more at risk for issues like learning disabilities. Black pregnant women are disproportionately affected by climate change in the U.S., research published in the journal JAMA Network Open showed, for many of the same reasons that people of color in general form another high-risk group.

People of color are more likely to have more underlying conditions and pre-existing illnesses that could make them especially vulnerable to climate effects, Dr. Mitchell says. At all income levels, they are significantly more likely than white people to have high rates of exposure to air pollution, water pollution, and toxic chemicals, and to suffer the resulting health effects, he says. They’re also more likely to be low-income, which makes it difficult to avoid or reduce environmental exposures and their health effects.

“Communities of all different colors are affected more severely by climate change than white communities,” Patel says. “Systemically, we have communities that have been drained of power and resources — or never had the power and resources to build healthy communities to begin with. I often say, we’ll all be impacted by, say, extreme weather conditions. The difference is, some communities will be able to rebuild and bounce back after a weather event destroys a town, and some will not because of these systemic issues.”

Additionally, low-income people tend to live in “urban heat islands,” areas that are hotter than neighboring communities, often due to a lack of green life and an overuse of cement. Low-income people may also be less likely to be able to afford air-conditioning, increasing their odds of being affected by the hotter temperature.

As with so many things, how climate change affects health is intersectional. Dr. Salas describes one recent patient, a man whose wife called 911 after he started acting confused. When he got to the hospital, his core temperature was 106 degrees Fahrenheit. “His body was literally cooking itself, and his brain couldn’t function,” Dr. Salas says. The man was low-income and elderly: He was living on the top floor of an apartment building, with no air-conditioning unit and one small window that didn’t open all the way. Climate change made the day hot, but being low-income placed the man in that un-air-conditioned room, which was even hotter, and being elderly made him even more susceptible to the extreme heat.

Dr. Mitchell describes working with people in a low-income housing development that was right next to a highway in Connecticut. “The [air] pollution and noise pollution were really, really bad, and harmful for people who had asthma. Their nurses would say to them, ‘You should close your windows,’ but they didn’t have air-conditioning. When it’s over 90 degrees, they’d have to have their windows open. But then their children would have asthma attacks and wind up in the hospital. The waiting list to change apartments was more than one-year long so there was little that they could do to change the situation.” 

Emphasizing all the ways climate change has affected our well-being — and what we’re at risk for if things continue along their same path — may be key to actually prompting real change.  

“Climate change is not just about polar bears and icebergs,” Dr. Salas tells Refinery29. “The way in which climate impacts health, and the way it’s disproportionately impacting some vulnerable populations, makes climate change personal. This is affecting your health, your kids’ health, your parents’ health, your neighbors’ health. And that can be a central driving force for climate action.”

“I think talking about the health effects makes climate change real to everyone,” Dr. Mitchell agrees. “It’s not just ‘out there,’ happening someplace else. A lot of families have someone with asthma, with lung disease, with heart disease. And so now they can’t go outside on certain days when it’s too hot or there is too much air pollution,” he says. “It’s not a political issue — health is health; it’s for everybody.”

While there are things individuals can do to protect themselves from the downstream effects of climate change — monitoring local air quality and staying indoors on hot or smoggy days; finding access to an air-conditioned space like a local library to use on hot days; having a plan for natural disaster; being aware of your local risk of vector-borne illness and using an appropriate repellent — these are short-term solutions for a long-term problem.

“In many ways I think we’re forced to put a Band-aid on a bullet wound,” Dr Salas acknowledges. “Studies show, for instance, that as A/C use increases, we’re creating more greenhouse gas emissions and more air pollution.” But as the world gets hotter, A/C can save lives. As such, she advocates for solutions that make it more accessible or affordable, like subsidizing electricity for cooling for those who need it (similar to heat subsidies), while at the same time pushing for bigger solutions, such as creating more green space in cities to reduce the urban heat island effect. Dr. Mitchell is also in favor of allowing health professionals to write prescriptions for air conditioning units, and of climate-protective solutions that benefit the more vulnerable communities. He talks about closing down fossil fuel power plants in urban areas, for instance, which has been associated with a drop in asthma symptoms among people who live near them — who are often predominately Black and low-income communities.

“The COVID-19 pandemic shows that we as a society can rapidly change our behavior. We can do the same thing with climate change, and emerge from the ashes of this stronger and more resilient. But prevention is so critical, as the pandemic has shown,” Dr. Salas says.

Patel says that while meaningful change requires action from policymakers, there’s at least one thing individuals can do to help move the needle on the climate crisis. “Vote. Vote for health,” she says. “Not just in the national elections; the local ones are so important, because local decisions impact parks, education, and infrastructure in a huge way. So get to know your local candidates. And vote — I can’t stress it enough.”