Much like the planet’s air temperature, diabetes rates are rising around the world.
Extreme heat, heavy floods, air pollution and infectious diseases will make dealing with diabetes harder and make the condition more common, research shows.
A serious chronic disease, diabetes is the leading cause of death for South African women.
It is caused by the body’s inability to produce (enough) insulin or use it properly. Insulin is the naturally occurring hormone that allows the body’s cells to take up sugar — also called glucose — from the blood so that its energy can be released to keep the body working. But when enough insulin isn’t made or the body can’t use it well, too much sugar is left in the bloodstream, which can lead to heart disease, vision loss, kidney problems, nerve damage and even amputation.
The world already does a poor job of looking after people with diabetes, especially when public health systems are under pressure. Adding climate change to the mix will make things even more difficult. So what’s the fix?
Types of diabetes
An estimated 15% of South African adults have type 2 diabetes, a form of the disease that develops over time, rather than someone being born with it. In 2011, it was estimated to be around 7%. Family history can contribute to the likelihood of getting the disease but almost 90% of cases are linked to being overweight.
Type 2 diabetes makes up about 96% of diabetes cases worldwide. It is sometimes referred to as a “lifestyle disease” because a healthy diet and exercise can prevent and, in some cases, reverse it. But many people with type 2 diabetes need to take a lab-made form of insulin to keep their blood sugar levels stable.
Doctors aren’t sure how to prevent type 1 diabetes, which is an autoimmune disease. This means that the body attacks itself by mistake. Type 1 diabetes is usually diagnosed in children or young adults and people then need daily insulin injections to control their blood sugar levels and stay healthy.
Hormonal changes during pregnancy can also change how insulin works, sometimes resulting in gestational diabetes. It could up the chance of a child developing obesity or type 2 diabetes. While it usually goes away after the baby is born, it increases the chances of the mother developing type 2 diabetes later in life.
Diabetes meets climate change
Extreme heat due to climate change affects our health, and research shows that in the US alone, 100 000 new diabetes cases could develop each year with a temperature increase of just 1°C, and heighten the chance of someone who already has diabetes ending up in hospital or the emergency room.
People with diabetes often have trouble keeping their body temperature in check through natural processes like sweating when it’s hot. Overheating can upset the way the body controls blood sugar levels, leading to dehydration or heat stroke which, without treatment, can quickly damage the brain, heart and kidneys.
These complications also influence how full hospitals are as well as the workload of health workers. In Brazil, researchers found that a 5°C increase in daily temperature led to 6% more diabetes-related hospitalisations.
Air pollution is a problem, too. Burning fossil fuels like coal, which is a big part of the reason for climate change, also makes the air dirty. Breathing in tiny bits of solid materials in the air increases the chances of developing diabetes, while the pollution from climate change-induced wildfires can heighten the chance of someone with diabetes needing hospital care.
Infectious diseases such as malaria and cholera will also become more common, with changing weather patterns shifting how far and fast germs spread. Because diabetes can weaken a person’s immune system, they can’t fight off germs as well as healthy people. That means they are more likely to get serious infections, including tuberculosis (TB), one of the main causes of death in South Africa.
Our reporting on the aftermath of the 2021 Durban floods showed more of the knock-on effects of climate-related floods. The closure of clinics, the loss of personal property like ID documents and being forced to move because of the disaster caused people to miss HIV treatment. Other studies have shown that in the face of climate disasters, TB spreads easier too. In the same way, if people with diabetes can’t get their daily insulin, it can quickly turn deadly.
Early warnings and sugar taxes
There are ways we can prepare for the impacts of climate change on diabetes and the healthcare systems that support patients. Early warnings, such as the soon-to-launch pilot programme through MomConnect that will alert pregnant women to coming heat waves, could be expanded.
But getting a handle on diabetes rates is the best place to start.
Clinics and hospitals in South Africa are required to provide treatment for people with diabetes. However, research shows that, in many cases, people aren’t put on the right treatment. A five-year plan released by the health department in 2022 to deal with noncommunicable diseases such as high blood pressure, obesity and diabetes could combat some of that.
Combating obesity, which affects one in four South Africans, will help.
Susan Goldstein, a public health researcher at Priceless SA told Mia Malan in a recent Health Beat episode that barring companies from marketing ultra-processed foods to children and requiring labels on food with too much salt, sugar or fat have been shown to curb sales. The health department’s 2023 draft legislation on the labelling and advertising of foodstuffs is promising.
Research shows that our sugar tax has worked. South Africans bought 28% fewer sugary beverages and manufacturers started cutting back on sugar in their products after it was enacted in 2018.
This story was produced by the Bhekisisa Centre for Health Journalism. Sign up for the newsletter.
