How Does Climate Change Impact Human Health?

Hi internet friends! How are you? I was pleasantly surprised by the high level of interest in the “What does it mean when your cell phone says “Unhealthy Air Quality for Sensitive Groups?” post I wrote last week. Turns out, people are interested in environmental health-related issues! Yay information! Due to the interest, I thought I’d roll out some more climate and health-related content. In today’s post, I am going to do a brief overview about how climate change can impact human health.

This has been a more nutrition-sided than environmental health-sided blog lately, but seeing as I’m going back to nutrition as my primary academic focus in fall, why not use my MPH in environmental health science while all the info is fresh!

Plus, it’s super interesting (at least to me, and I hope to many of you) and motivating to make actionable changes in your life and advocate for even more.

So how does climate change impact human health? Well, in a lot of ways! I’m going to do a brief overview of a variety of ways climate change can impact health. 

Let me know in the comments below (or on Instagram, Twitter, or YouTube) if you’d like more information or a specific post on any of the below subtopics.

I feel very fortunate to have gotten my MPH in Environmental Health Science with my certificate in Climate & Health from the university that pioneered an academic focus in that area. I realize this is a huge privilege to have learned so much about how climate change impacts human health, and I want to share what I’ve learned with others. So please ask questions about anything! I am happy to elaborate! 

**Don’t want to read? Check out the video version here, or scroll to the bottom of this post.

Air Pollution

Air pollution causes an estimated 8 million deaths each year.  Poor air quality increases risks of respiratory diseases, cardiovascular diseases, eye irritation, skin diseases, and neuropsychiatric complications, and even cancer. Air pollution can exacerbate existing medical conditions such as asthma high blood pressure. 

Human-produced indoor and outdoor (ambient) air pollution are both serious sources of pollution, both of which contribute to climate change and cause human health impacts.

*Quick side note: does it make sense to you how climate change even occurs? I’d be happy to write a separate post about it. Let me know if that’s of interest!

Allergens

Got allergies? I have some sad news for you. Climate change can make your allergies worse. How? By changing temperature and precipitation patterns that characterize different seasons of the year, climate change may prolong plant pollination period, and thus, lengthen and exacerbate the amount of allergens that make their way into the air in many areas.

Additionally, elevated CO2 concentrations and temperatures increase pollen output of plants. Meaning more stuff will is in the air to make you sneezy, itchy, weezy, etc.

Vector Borne Diseases

Vector borne diseases are those transmitted by a vector. Vectors are living organisms that carry disease between humans and other creatures. Examples include blood-sucking insects, ticks, fleas, snails, mosquitoes, black flies, and lice.

Examples of vector borne disease include malaria, dengue, and yellow fever. 

Where does climate change come in? Well, climate change is causing shifts in geographical and seasonal distribution of vector populations. This means vectors have longer seasons to spread disease, as well as new, and often expanded territory. 

Nutrient Density of Food

Climate change is making your granola bar less nutritious?! Well, yes. How? Increased levels of CO2 impact how plants grow, and cause them to grow more quickly. This gives them less time to absorb nutrients from the soil, decreasing the uptake of certain vitamins and minerals, and even impacting the amount of protein in certain crops, including wheat. 

I wrote all about this in this blog post, if you’re interested in reading more here.

Additionally, due to human activity, there are now higher levels of environmental toxins and heavy metals in soil. Examples include arsenic, which is all up in rice, or glyphosate – a pesticide – that’s in oodles of crops. This increases the levels of these environmental toxins and heavy metals that ends up in your food.

Food Security

Agriculture is an industry highly contingent upon weather patterns. Extreme temperatures and precipitation patterns (including droughts and floods) directly impact crop yields. As we’ve seen in the Midwest this summer, these extreme growing conditions can really impact the amount of food available, which can also impact food prices (typically, the lower the crop yield, the higher the price of food). This can impact the amount of food available or affordable to many people across the globe. 

Furthermore, climate change and elevated levels of CO2 can make it easier for invasive species to spread and thrive in new territories, which can present as an additional threat to crop foods. 

Having a nutritious, adequate and diverse diet is important for overall human health, and climate change is a direct and serious threat to maintaining a healthful diet. 

Mental Health

Climate change is changing our world, and our immediate environments. For many of us, for a variety of reasons, this can be a cause of distress and mental illness. 

For example, victims of natural disasters (which are more frequent and intense with climate change) are at increased risk of anxiety, depression, suicide, and PTSD.

But there are other, more gradual ways climate change can lead to mental distress. Perhaps you live in a flood zone and it’s extra rainy, or you are unsure if you will be able to grow crops next season. Or, perhaps, you plain feel overwhelmed by the realities of climate change. All of these climate change-driven scenarios can lead to increased risk of mental illness over time.

Extreme Temperatures:

Heat waves are increasing in frequency and intensity as a result of climate change. This is concerning, because it can increase risks of heat-related deaths due to stroke, and/or exacerbating other cardiovascular conditions. 

While it’s easy to just assume AC will save us all, not everyone has or can afford AC, and many are at risk from the dangers of heat.

Extreme Weather Events

In addition to heat waves, other extreme weather events like hurricanes, floods, and droughts are increasing in frequency and intensity due to climate change. These storms can cause death by injury and drowning, but can also cause other health problems, especially if water is involved, which can increase rates of waterborne illness, and mold exposure. 

Food and Waterborne Illnesses 

Climate change can cause shifts in precipitation patterns and temperatures, and cause sea level rise. This may increase risks of waterborne illnesses due to pathogen contamination in the water and associated diarrheal disease. Pathogens may also thrive in warmer conditions caused by climate change.

Diarrheal disease may not be a major concern for most of the developed world, but is a serious public health concern in many developing countries, and a leading cause of death worldwide.

Climate change can also cause increased exposure to certain chemical hazards and cyanotoxins, causing further concern.

Forced Migration

Climate change can cause environments to become inhabitable by causing conditions to become too hot or cold, too wet or dry, or too limited with once abundant natural resources such as drinking water. 

Additionally, extreme weather events may destroy some habitable areas. Some may be forced to leave their homes. These environmental-driven refugees are at risk of physical and mental health risks associated with being a refugee due to lack of access to healthcare and possible mental distress of being a refugee. 

Wildfires

Most wildfires are caused by humans. However, climate change can increase conditions that make it easy for wildfires start and to spread. 

Wildfires are a threat to humans by direct injury and exposure to particulate matter. Poor air quality can cause respiratory and cardiovascular distress to humans, especially vulnerable populations.

*I am planning a whole separate post about wildfires, so stay tuned!

Who is at Risk?

Well, everyone will be affected by climate change in some way. However, certain groups will feel more affects than others. People living in coastal communities, megacities, polar, and mountainous regions are especially at risk. 

Benefits?

There are a few health-related benefits of climate change. Some places with cold winters may experience fewer extreme cold days and fewer cold-related deaths. Additionally, some places that were once too cold to grow crops may be able to grow them with rising temperatures, and some areas may experience temperature or precipitation shifts that lead to fewer allergens in the air.

While it’s important to acknowledge these possible benefits, when it comes to climate and health, the negatives and risks far outweigh the potential positives. Climate change is a real, serious threat to human health and should be taken seriously. 

Take Home:

Climate change is a serious threat that can impact human health in many ways. It puts all of us, especially vulnerable and marginalized populations or those living in climate change hotspots, at risk for a variety of health impacts. 

Acknowledging and understanding the relation between climate and health is often a powerful way to begin conversation and advocate for action and change. After all, we all wish health and happiness to ourselves and those we love!

It’s a great idea to educate yourself and others about how climate change can impact health. Not only will it help you understand your own health, and rates of disease around the world, it can be powerful for motivating meaningful change.

I hope you found this somewhat helpful if you’ve ever asked yourself “How does climate change impact human health?” As I mentioned above, if you have questions or want further elaboration on any topic, please feel free to contact me here on the blog, or on Instagram, Twitter, or YouTube!