Talking extreme heat with U of M
MINNEAPOLIS/ST. PAUL (06/13/2023) — With hot summer days already being experienced across the country, it’s important to be aware of the impacts of extreme heat and how to take care of your health while enjoying outdoor activities.
Vishnu Laalitha Surapaneni, MD, MPH, with the University of Minnesota Medical School and M Health Fairview, discusses extreme heat and the effect it can have on an individual’s health.
Q: What is extreme heat and why is it dangerous to our health?
Dr. Surapaneni: Extreme heat conditions are defined locally as weather that is much hotter than average for a particular time and place. Because of climate change, hotter than usual days and nights are becoming more common.
The human body needs to stay at an optimal temperature range — around 98.6 Fahrenheit — to function. When there is excess heat created in the body, like when we exercise, we need to find a way to get rid of it. That’s when the body turns on its ‘internal air conditioning system’ by sweating.
When sweat evaporates, it pulls heat from the body and dumps it into the air around us. However, trouble starts when it’s too hot or too humid and our body cannot get rid of the heat effectively. As heat builds up in our body, it leads to heat-related illnesses like heat exhaustion and heat stroke. It can also worsen heart failure, cause kidney damage or lead to strokes.
Q: What are some of the most significant health risks associated with extreme heat?
Dr. Surapaneni: Symptoms of heat illness can range from excessing sweating, thirst and muscle cramps to headache, lightheadedness or fainting. If you don’t pay attention to these symptoms and take immediate precautions, you may experience a medical emergency like heat stroke which can involve confusion, a high fever of over 103 Fahrenheit and loss of consciousness. If not treated immediately, heat stroke can be deadly.
Even if you don’t experience a heat stroke, extreme heat can take a toll. For example, chronic dehydration can lead to chronic kidney failure. Pregnant women can experience preterm labor or have babies with low birth weight. Extreme heat also worsens air quality, leading to asthma attacks. Those who are older, have medical conditions like diabetes or those taking medications such as for anxiety, depression or high blood pressure, can be especially sensitive to the health impacts of extreme heat.
It’s important to note extreme heat can impact our health even when we are indoors. Especially for those living with no air conditioning, indoor temperatures can reach levels similar to or higher than outdoor temperatures.
Q: Who is at the most risk?
Dr. Surapaneni: All of us are at risk from extreme heat, but some groups are more vulnerable than others. Those who are exposed to more heat in their daily lives are at particular risk. Outdoor workers like farmers, construction and delivery workers, those lacking in housing, or athletes are more likely to suffer heat illness. Heat illness during practice or competition is a leading cause of death and disability among U.S. high school athletes.
Additionally, older people, pregnant people and young children are less able to regulate their body temperature and are at higher risk for heat-related illness. Heat-related mortality for people over 65 is estimated to have increased by approximately 74% from 2000-2004 to 2017-2021. People who have health conditions like heart failure, hypertension or diabetes — and especially those taking medications for these conditions — are more likely to suffer dehydration or heat stroke.
Q: What preventative measures can be taken to protect ourselves against extreme heat?
Dr. Surapaneni: First, we need to be aware that extreme heat is a serious public health issue in Minnesota. This means monitoring the local heat index daily and being up to date with extreme heat warnings from the National Weather Service.
When trying to protect yourself from heat, be sure to:
- Limit exposure to heat as much as possible
- Keep yourself cool
- Stay hydrated
Stay in areas with air conditioning or cooler parts of the house like the basement. It is imperative to stay hydrated, so bring water along with you. If you're adequately hydrated, your urine will be pale yellow. Take breaks in cool shaded areas if you are exerting yourself. Make sure that at night, you give your body a chance to cool down.
Q: Why is climate change a health equity issue? What can be done to help?
Dr. Surapaneni: Often, the advice for how people can protect themselves from extreme heat is not practical for everyone. For example, farmers cannot work indoors. Low-income families might not be able to afford air conditioning, and the unhoused cannot take refuge from heat even if they know that temperatures are at dangerous levels. However, we can act collectively to protect all community members—as a neighborhood, a school or through local and federal policy.
Collective action could be in the form of making sure your child’s school has an indoor and outdoor heat safety plan or establishing a neighborhood watch to ensure elderly neighbors limit their time outdoors and have access to air conditioning, or implementing workplace regulations to ensure outdoor workers are protected from excess heat.
Cities in Oregon and California are also developing heat safety infrastructure called cooling centers. These are air conditioned places where people can go during extreme heat. This is especially important for low-income households who do not have air conditioning or those experiencing homelessness. The bottom line is that extreme heat is something we cannot afford to avoid completely. It’s time we start planning to avoid the health impacts.
Vishnu Laalitha Surapaneni, MD, MPH, is an assistant professor at the Medical School and a hospitalist at the M Health Fairview University of Minnesota Medical Center. She specializes in climate change and its impact on human health. Dr. Surapaneni works with community organizations to advocate for just climate policies and has provided expert testimony at the Minnesota State Capitol on the public health impacts of climate change. Follow her @LaaliMD on Twitter for information on how climate change impacts our health and the role health professionals can play in climate action, such as urban greening, access to clean renewable energy and urban cooling centers.
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