The ability to escape, or at least mitigate, the effects of heat exposure is even more critical to people’s health as climate change increases the average temperatures and frequency of heat waves. Staying hydrated, seeking shade or cooling centers, and trying not to spend too much time in the sun are often adequate precautions for people’s physical health, but what public health and health care systems are only now beginning to acknowledge is the impact that high heat and heat waves can have on the mental health of Black, Indigenous, and other people of color (BIPOC).

BIPOC are more likely to reside in hotter regions that trap and radiate heat and are increasingly likely to suffer from mental health illnesses, yet have fewer avenues to access supportive and sometimes life-saving resources. Advocates and physicians say that the mental health and well-being of many BIPOC, especially those who are low earning or housing insecure, are often addressed only when the circumstances become dire or when emergency care is sought.

Sam Castro, the director of diversity, equity, and inclusion at Valle del Sol, a community health organization based in Arizona, says that for someone to feel healthy, they need structures for resources, transportation, and job access built into their lives—otherwise, added stress only puts pressure on the gaps. And BIPOC and other marginalized communities continually find themselves pushed into those gaps.

“There are many [negative] social determinants of health that marginalized communities already experience—like barriers to proper health and wellness,” Castro said. “I will say, with the heat wave going on, we’ve already been experiencing these disparities during these times … When you don’t feel good physically, you’re not going to feel good mentally, either.” 

Extreme heat impacts every single component of daily life, including mental health. In 169 out of 175 metropolitan areas in the U.S., people of color, on average, are more likely to live in neighborhoods plagued by the urban heat island effect. Wealth and income are also determinative of residing in a heat island: The New York Times found that cities can have temperature disparities as great as 20 degrees Fahrenheit, with heat islands often overlapping with lower-income and BIPOC neighborhoods. Black Americans, who comprise 13.6% of the U.S. population, account for nearly 20% of those living below the poverty line. Castro says that BIPOC communities in Phoenix suffer a lack of public transportation access, affordable housing, mental health care insurance coverage, and culturally competent therapists and counselors. 

“That coincides with climate change and our environment and the heat wave in general,” Castro said. “If you are in a place where your physical and mental health already isn’t addressed, it’s going to be worse with the heat wave.” 

Heat is normal, extreme heat is not 

Heat cycles are part of our planet’s environment. The earth’s weather systems naturally fluctuate, and each season provides balance to sensitive ecosystems. The three-to-four warmest months of the year allow soils to grow important bacteria, animals to feed and raise their newborn offspring before heading into fall, and tree leaves to dry up ahead of autumn when they fall off of tree branches, which protects branches from gathering too much snow and breaking. 

Extreme heat, however, is a warning sign that our ecosystems are becoming increasingly erratic and dangerously out of balance. The increasing temperatures that are “too hot for humans” are accompanied by concurrent crises with wildfires, droughts, and other forms of ecological imbalances. And they show no signs of receding.

Since the 1960s, U.S. summers have grown hotter and longer on average; six decades ago, the average heat wave lasted about three days, one day less than they do now. The heat wave season, as the Environmental Protection Agency calls it, lasts almost 50 days longer than it did 60 years ago, meaning that there’s a longer time period during which people can suffer heat stroke, dehydration, and other heat-caused illnesses. Longer, hotter summers also means that there are warmer evenings and less time for people’s bodies to recover from heat, as they usually would at night. 

Additionally, scientists say that the number of hot months that we associate with summer will increase. If the U.S. federal government continues to rely on an extractive economy and refuses to take substantive climate mitigation efforts, by 2100—or three generations from now—so-called summer will last six months, with winter lasting two months. The negative impacts we’re now seeing from prolonged periods of heat and extreme temperatures will only get worse.

However, advocates say that what these predictions critically miss is the fact that heat is already plaguing some more than others, and rising temperatures are putting even more strain on the mental health and well-being of underserved communities. 

Extreme heat adds additional stress to the body 

Amruta Nori-Sarma, an assistant professor in the Environmental Health Department at Boston University School of Public Health, studied the relationship between extreme heat and emergency room visits of those experiencing a mental health crisis, finding a direct connection between environmental temperature and one’s well-being. 

Having reviewed almost 3.5 million emergency room visits among 2.2 million individuals from a population with employer-provided medical insurance or Medicare Advantage, Nori-Sarma and her research team found that rates of visits increased similarly for those with a variety of conditions, including substance use disorders, mood disorders or anxiety, stress-related illnesses or schizophrenia, self-harm, and adult onset personality disorders. Heat-induced mental health stress was also consistently worse for those with pre-existing mental health illnesses, and Nori-Sarma noted that some people may visit emergency rooms seeking relief from extreme heat. 

“What we saw was that the rates of emergency department visits for all of these different types of outcomes increased similarly with increasing temperature,” Nori-Sarma said. In other words, as heat increased, so did the number of people seeking crisis support no matter the underlying mental health stress. 

Nori-Sarma’s study included data from seven major climate regions in the U.S. and found that cities in the Pacific Northwest, Northeast, and northern Midwest states saw greater numbers of emergency room visits, which she predicted was due to the fact that residents were experiencing extreme heat for the first time and that buildings and homes might not be outfitted with air conditioning units. According to the U.S. Global Change Research Program, heat wave intensity in northern regions is predicted to increase. 

With much of the research around heat focused on how it affects physical health, Nori-Sarma wanted her research to underscore the connection between heat and mental health. The EPA doesn’t currently list mental or emotional well-being as a heat-related illness, but when it comes to heat, mental health and physical health are so intertwined that differentiating between the two is nearly impossible. Dr. Yaminikrishna Sabesan, the associate chief medical officer at Mercy Care, a not-for-profit Medicaid managed-care health plan for low-income Arizona residents, explains that heat can seriously impact brain chemistry and the body’s core temperature. 

Essentially, heat affects hormone secretion, so when someone’s stress hormone is high from heat, they can become irritable, experience emotional swings, and lose concentration. Some psychiatric drugs and other medications interfere with the body’s core temperature or may even dehydrate the body, which means that someone might not be aware that they should be drinking more water than they think they need to, making them even more vulnerable to the effects of intense heat. 

To fight some of these impacts, Sabesan says that Mercy Care helps patients apply for subsidies for air conditioning units—which can prove to be critical, and expensive, medicine during a heat wave—as well as provides support against eviction proceedings. 

If you are in a place where your physical and mental health already isn’t addressed, it’s going to be worse with the heat wave.

Sam Castro

But it’s not only the more extreme experiences of heat that concern her, Sabesan says. The gradual changes in mental health triggered by heat can grow into more severe consequences later on. Many people underestimate how loneliness can be a side effect of staying indoors to regulate heat exposure. Older patients, who are less mobile and may have smaller social networks, are especially susceptible to feelings of isolation and how they can impact mental health, as seen during the pandemic. 

“If somebody’s already depressed and anxious, and now we are making them stay in a home, that is a toll on their mental well-being,” Sabesan said. “These are interrelated.”

Housing and environmental injustice create fertile ground for heat disparities

The heat disparities that exist in BIPOC communities, particularly in areas heavily populated by Black people, are a product of federal housing segregation known as redlining. Mortgage lenders effectively forced Black and other nonwhite people away from the suburbs and into urban areas, ultimately creating neighborhoods that most entities, from governing bodies to supermarket chain stores, avoided putting money or public services into, including critical access to green spaces, energy-efficient infrastructure, and housing. While redlining is no longer legal, it kept housing values low in majority-BIPOC neighborhoods for decades, the effects of which continue to prevent BIPOC families from building and transferring intergenerational wealth. Now, research has proved a direct correlation between historically redlined neighborhoods and heat. 

These neighborhoods experience the hottest of summer days because cement, asphalt, and other artificial structures absorb, trap, and radiate heat, otherwise known as the urban heat island effect. Juan Declet-Barreto, a senior social scientist for climate vulnerability for the Climate and Energy Program at the Union of Concerned Scientists, says that micro heat islands exist within cities as a result of urban planning decisions that disregard the health and well-being of BIPOC and low-income communities, such as highways and major transportation projects that cut through neighborhoods, factories built next door to schools and playgrounds, and the use of inefficient materials and design in the construction of housing. 

“When you look at the full structural feature of what the conditions in neighborhoods [are like] where it’s hotter, where there are the worst health outcomes, you’ll see that it’s not just the chronic disinvestment from redlining,” said Declet-Barreto. “It’s also a lack of access to good jobs and health care.”

In other words, the danger posed by extreme heat to low-income BIPOC communities is a product of federally sanctioned housing discrimination and an exacerbating element on top of these existing injustices. 

Heat-induced emotional stress compounds existing mental health needs

For most people, heat isn’t creating new mental health struggles, but it is putting pressure on already existing challenges. Nirmita Panchal, a senior policy analyst for the Kaiser Family Foundation, says that as a result of pandemic stress, anxiety and depression have risen across the country, disproportionately affecting communities of color, particularly Black and Latinx communities. The long-term consequences of depression are also more severe for communities of color, leading to other health and economic challenges. 

Black and Latinx people are less likely to receive needed mental health care despite the need. For starters, Panchal says, BIPOC are more likely to be uninsured, and generally speaking, those who are uninsured are far less likely to seek or access mental health treatment. According to the most recent Kaiser Family Foundation analysis, six in 10 people in the coverage gap—or those lacking insurance from private or public marketplaces—are people of color. That means those six in 10 people who have moderate-to-severe anxiety or depression are less likely to receive treatment, Panchal says.

“When we’re talking about mental health of individuals in the BIPOC and marginalized communities, we’re actually talking about the disassociation or lack of care for those populations by the greater population,” said Franklyn Smith, the director of community resources for Freedom Project Washington, a Seattle-based organization that works to dismantle the system of mass incarceration and heal its traumatic effects. 

Smith says that the organization’s ethos is built on creating a space where every member of the organization, from staff to clients, can talk about what they’ve been through and what trauma they have survived. It’s tricky, Smith says, because mental health isn’t visible, and by the time signs that something may be wrong begin to show up, the mental health condition may take even more time to heal. 

As someone who works in the mental health field serving patients of color, and having sought counseling herself, Castro knows firsthand that mental health care is a field that discriminates. That’s often because the very systems that prioritize individual health outcomes are the ones pushing whole communities to the margins. The emphasis on individualism in U.S. culture obscures how emotional and mental health issues are connected to other systems of power, the same systems that enable climate change and maintain social inequities that put marginalized communities at even greater risk from extreme heat.

Smith says the idea that those systems of power have no effect on mental health is a lie, and understanding how outside pressures lead to internal reactions is essential to addressing the particular mental health struggles BIPOC can face. For instance, generational traumas from the enslavement of Africans and African Americans has a real impact on people’s lives today, Smith says. These systemic pressures are the underlying factors of mental health that later get compounded from environmental and climate issues like heat. 

Ultimately, he says that the key is to check in with someone before they ask for help, be a friend who can call someone out on their behavior, and take responsibility for your actions. These are all steps of building a community, which during times of stress, from personal to environmental, can be invaluable. For instance, during last year’s deadly heat wave in the Pacific Northwest, Freedom Project Washington shifted their priorities to meet the community’s immediate needs: offering water, fans, and a space to get out of the heat. 

There are community organizations like Castro’s working to provide care to those who typically don’t have access, but climate change and a lack of funding for infrastructure to address climate change are making it even more difficult to navigate existing challenges. Those who live in underserved communities are likely not able to afford or access health care, which then leads to stress, which then can lead to maladaptive behaviors requiring mental health care.

“It’s all a cycle,” Castro said.