Human pressures on the global environment are wreaking havoc on our planet, but they are also an increasingly significant threat to human health. Climate change is the ‘greatest threat to human health in history’, far greater than risks posed by viruses and diseases.
We need the same urgency to treat climate change as when everyone jumped to combat the COVID-19 pandemic. Otherwise - our health is due for a downward spiral in coming years.
Here are just 10 ways we’re already seeing climate change impacting the human body – some you may expect, while some are more discreet.
10. Heat stress on the heart
Record-breaking temperatures are going to become more frequent as the global temperature either reaches or exceeds 1.5 degrees Celsius of warming over the next 20 years. More and more, we are hearing of deadly heatwaves and wildfires sweeping across hot, dry expanses of land. Extreme temperatures have been found to kill 5 million people each year.
Those who manage to live will be forced to deal with the consequences of excessively high temperatures in their everyday lives.
When temperatures are higher, so is cardiac demand. The heart must pump harder and faster to redistribute and increase blood flow to the skin to cool the body. People with heart diseases, whose hearts are weakened, are particularly at risk of heart failure and heat stroke in hot weather as their organs struggle to function properly with the added stress.
9. Sleep disruption
A 2022 study led by Kelton Minor, of the University of Copenhagen’s Centre for Social Data Science, finds that rising temperatures driven by climate change are significantly decreasing the amount of sleep people all around the world are having.
Minor gathered data using sleep-tracking wristbands on 47,000 people across 68 countries.
“Sleep is a time our bodies restore and repair,” he tells Euronews Green. “It’s important for our functioning and performance, but also for our mental wellbeing.”
But when he measured the sleep of participants, Minor found “on warmer than average nights, people slept less.” Those shorter nights of sleep over a prolonged time eventually lead to adverse health outcomes.
However, everyone is not equally impacted by the warming temperatures. “Even though everyone is affected by this sleep burden, people are affected unequally and most of the burden goes on to groups that historically have been either disadvantaged or are vulnerable to heat in different ways,” he explains.
Namely "the elderly, females, and residents of lower income countries".
8. Respiratory Issues
Ozone is a gas naturally found in the Earth’s upper atmosphere, providing a shield from the sun’s ultraviolet rays. Ground level ozone, which is dangerous for our health, is produced when pollutants emitted by manmade sources like cars or chemical plants react in the presence of sunlight.
Increased ground level ozone and particulate matter - the tiny floating solid and liquid particles of matter in the air produced by natural and manmade sources - have been found to lead to diminished lung function, especially if a person is exposed to air pollution in childhood.
The main concerns resulting from air pollution are: asthma, rhinosinusitis, chronic obstructive pulmonary disease and respiratory tract infections.
On unusually hot days, which we will continue to see more of in future years, ground ozone levels can reach unhealthy levels and there is an increased risk of breathing air containing ozone.
This can lead either to conditions as harmless as a cough, or as dangerous as making it hard to breathe and increasing the frequency of asthma attacks.
In Canada, one woman became the first patient in the world to be diagnosed as suffering from ‘climate change’ after she developed breathing difficulties in a heatwave.
7. Kidney damage
Dehydration from heat exposure can damage the kidneys, which depend on water to help remove waste from our blood in the form of urine.
When excess amounts of water are lost from dehydration, urine contains a higher concentration of minerals and waste products. This can lead to the formation of crystals that can become kidney stones, adversely impacting kidney function and causing various painful symptoms like nausea, lower back pain, and difficulty passing urine.
In older adults, whose kidneys may already be failing, dehydration could be the final straw that kills them.
6. Aggravated allergies
With rising CO2 levels, which have increased by 9 per cent since 2005 and by 31 per cent since 1950, the amount of pollen increases as a consequence of higher rates of photosynthesis.
This rise leads to worsening allergy/hayfever symptoms such as sneezing, coughing, itchy eyes, headache and earache.
5. Damage to heart circulation
When air pollutants travel into your bloodstream through your lungs and into your heart, the risk of developing heart and circulatory diseases increases as blood vessels narrow and harden.
A 2018 study carried out in London found that with increased air pollution, particulate matter enters the bloodstream, making the blood more sticky and forcing the heart to work harder to pump around the body.
The result can lead to the structure of the heart changing with the bottom two chambers becoming larger and more dilated - a change often seen in the early stages of heart failure.
One of the lesser known effects of air pollution is being studied by Dr Gareth Nye, Lecturer of anatomy and physiology at the University of Chester, UK, who researches air pollution’s impact on fertility.
“A paper looking at 18,000 couples in China found that those living with moderately higher levels of small-particle pollution had a 20 per cent greater risk of infertility,” Nye tells Euronews Green.
He describes another US study showing how air pollution impacts maturation of eggs too.
“With up to 30 per cent of couples struggling to conceive and having no recognised reason, it is now more important than ever to look at air pollution as a possible cause.”
As temperatures increase, so do food shortages. This is seen most clearly in communities whose livelihoods depend on agriculture and fishing, such as in the Global South.
Changing precipitation patterns, rising ocean temperatures and extreme weather events are contributing to severe malnutrition in the developing world. Malnutrition leads to a variety of health complications: heart disease, cancer, diabetes, and impaired growth.
And in more developed countries, food shortages caused by climate change will cause food prices to soar, as we are already seeing.
People will only be able to cope by turning to nutrient-poor food sources to fill empty stomachs, which could lead to obesity and micronutrient malnutrition.
2. Mental health
Physical health isn’t the only way we’re impacted by climate change though. Following global disasters like wildfires, floods, or hurricanes, mental health problems are only getting worse.
Take Hurricane Katrina in 2005, one of the worst disasters in American history. It was found that at least 90 per cent of the 8,000 patients treated in the aftermath of Katrina suffered with long-term anxiety following the storm.
If someone experiences food insecurity, the loss of all their possessions and the deaths of people they love – they will no doubt suffer in coming years from the trauma they endured, potentially causing post-traumatic stress disorder (PTSD) or even suicide.
Eco-anxiety is also on the rise, especially among young people who feel daunted by the prospects of their future world.
A global study published in 2021 found that 60 per cent of 10,000 young people from countries all over the world feel very or extremely worried about climate change. 56 per cent said they thought humanity was doomed.
“They felt like their future couldn’t be positive, but there is nothing they could do about it,” Steve Simpson, Professor of Marine Biology and Global Change at the University of Bristol, told Euronews Green.
“They could only sense a declining state of the planet, but felt powerless to have influence.
1. Microplastics found in our bodies
It isn’t just climate change that harms our health, it’s the disregard for the wellness of our planet, seen clearly in our overuse of (and reliance on) plastics.
Microplastics, extremely small pieces of plastic debris found in the environment, are being found in the human body. In March, they were found in human blood for the first time – we’re talking plastic used to make drinking bottles, packaging and shopping bags. There is fear among scientists that these nanoparticles reach all the way to our organs through the bloodstream.
Babies have been found to have 15 times more microplastics in their faeces than adults, research finds, most probably ingested from plastic dummies and microplastics in carpets.
There is ongoing research as to what the effects of microplastics are on human health.
How can we take action?
As we become more and more aware of the impact climate change has on our health, there is hope that action will be taken to change the future.
The Paris Agreement holds countries to account to limit global warming to below 2 degrees Celsius. Scientists and activists are offering solutions to mitigate risks. Governments are being challenged to act, and quickly. There is hope.
But without urgent action, human health will continue to be adversely affected by climate change and the fate of future generations looks grim.