Human pressures on the global environment are wreaking havoc on our planet, but they are also a growing threat to human health. Climate change is the ‘the greatest threat to human health in history’, much higher than risks posed by viruses and diseases.
We need the same urgency to deal with climate change as when everyone jumped to fight the COVID-19 pandemic. Otherwise – our health is due to a downward spiral in the coming years.
Here are just 10 ways we are already seeing climate change impact the human body – some you might expect, while others are more muted.
10. Heat stress on the heart
Record high temperatures will become more frequent as global temperature reaches or exceeds 1.5 degrees Celsius of warming over the next 20 years. More and more, we hear of deadly heat waves and wildfires sweeping across hot, dry stretches of land. Extreme temperatures proved kills 5 million people every year.
Those who manage to survive will be forced to deal with the consequences of excessively high temperatures in their daily lives.
When temperatures are higher, heart demand too. The heart must pump harder and faster to redistribute and increase blood flow to the skin to cool the body. People with heart disease, 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 by Kelton Minor, from the Center for Social Data Science at the University of Copenhagen, finds that rising temperatures driven by climate change are significantly decrease the amount of sleep people all over the world have.
Minor collected data using sleep tracking bracelets on 47,000 people in 68 countries.
“Sleep is a time when our body restores and repairs,” he told Euronews Green. “It’s important for our functioning and performance, but also for our mental well-being.”
But when he measured participants’ sleep, Minor found that “on warmer than average nights, people slept less.” These shorter nights of sleep over an extended period end up having adverse health effects.
However, not everyone is equally affected by warming temperatures. “Even though everyone is affected by this sleep load, people are affected unequally, and most of the load falls on groups that have historically been disadvantaged or heat-vulnerable in different ways,” he explains.
Namely “the elderly, women and residents of low-income countries”.
8. Respiratory problems
Ozone is a gas naturally present in the Earth’s upper atmosphere, which protects against the sun’s ultraviolet rays. Ground-level ozone, which is dangerous to our health, is produced when pollutants emitted by man-made sources such as cars or chemical factories react in the presence of sunlight.
Increase in ozone at ground level and special case – the tiny particles of solid and liquid matter floating in the air produced by both natural and man-made sources – have been shown to cause decreased lung function, particularly if a person is exposed to air pollution in childhood.
The main concerns resulting from air pollution are: asthma, rhinosinusitischronic obstructive pulmonary disease and respiratory tract infections.
On exceptionally hot days, which we will continue to see more and more in the years to come, ground-level ozone levels can reach unhealthy levels and there is an increase risk of breathing air containing ozone.
This can lead to conditions as harmless as a cough or as dangerous as making it difficult to breathe and increasing the frequency of asthma attacks.
In Canada, a woman has become the world’s first patient to be diagnosed with ‘climate change’‘ after developing breathing difficulties during a heat wave.
7. Kidney damage
Dehydration from heat exposure can damage the kidneys, which rely on water to help remove waste from our blood in the form of urine.
When excessive amounts of water are lost due to dehydration, urine contains a higher concentration of minerals and waste products. This can lead to the formation of crystals which can become kidney stones, impair kidney function and cause various painful symptoms like nausea, lower back pain and difficulty urinating.
In older people, whose kidneys may already be failing, dehydration could be the last straw that kills them.
6. Aggravated Allergies
With rising CO2 levels, who have increased by 9% since 2005 and by 31% since 1950, the amount of pollen is increasing due to higher rates of photosynthesis.
This increase leads to worsening of allergy/hay fever symptoms such as sneezing, coughing, itchy eyes, headaches and earaches.
5. Damage to heart circulation
When airborne pollutants enter your bloodstream through your lungs and heart, the risk of developing heart and circulatory disease increases as blood vessels narrow and harden.
A study carried out in 2018 in London found that with increasing air pollution, particles enter the bloodstream, making the blood stickier and forcing the heart to work harder to pump throughout the body.
The result can cause the structure of the heart to change, with the two lower 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 studied by Dr Gareth Nye, Professor of Anatomy and Physiology at the University of Chester, UK, who studies air pollution impact on fertility.
“An article looking at 18,000 couples in China found that those who lived with moderately higher levels of small particle pollution had a 20% higher risk of infertility,” Nye told Euronews Green.
He describes another US study showing how air pollution also affects egg maturation.
“With up to 30% of couples struggling to conceive and having no recognized reason, it is now more important than ever to consider air pollution as a possible cause.”
As temperatures rise, 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 rainfall patterns, rising ocean temperatures and extreme weather events contribute to severe malnutrition in the developing world. Malnutrition leads to various health complications: heart disease, cancer, diabetes and impaired growth.
And in more developed countries, food shortages caused by climate change will lead to soaring food prices, 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 is not the only way we are affected by climate change. In the aftermath of global disasters such as wildfires, floods or hurricanes, mental health issues only get worse.
Take Hurricane Katrina in 2005, one of the worst disasters in American history. It was found that at least 90% of the 8,000 patients treated following Katrina suffered from long-term anxiety after the storm.
If someone experiences food insecurity, loss of all their possessions and the death of people they love, there is no doubt that they will suffer in the years to come from the trauma they have suffered, which could cause post-traumatic stress disorder (PTSD) or even suicide.
Eco-anxiety is also on the riseespecially among young people who feel intimidated by the prospects of their future world.
A global study published in 2021 revealed that 60% of 10,000 young people in countries around the world feel very or extremely concerned about climate change. 56% said they thought humanity was doomed.
“They felt like their future couldn’t be positive, but there was 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 state of planetary decline, but felt powerless to have any influence.
1. Microplastics present in our body
It’s not just climate change that’s harming our health, it’s the disregard for the well-being of our planet, which is clearly seen in our overuse (and reliance on) plastics.
Microplastics, extremely small pieces of plastic debris found in the environment, find their way into the human body. In March, they have been found in human blood for the first time – we are talking about plastic used to make bottles, packaging and shopping bags. Scientists fear that these nanoparticles reach our organs through the bloodstream.
It was discovered that the babies had 15 times more microplastics in their faeces than adults, according to research, most likely ingested by plastic mannequins and microplastics in carpets.
Research is ongoing on the effects of microplastics on human health.
How can we act?
As we become increasingly aware of the impact of climate change on our health, there is hope that action will be taken to change the future.
The Paris Agreement obliges countries to limit global warming to less than 2 degrees Celsius. Scientists and activists are propose solutions to mitigate risks. Governments are challenged to act, and quickly. There is hope.
But without urgent action, human health will continue to be affected by climate change and the fate of future generations looks bleak.