New Study Shows an Eerie Association Between Climate Change and Diabetes
Climate change is often treated by skeptics as something entirely separate from human health. Temperatures rising, ice caps melting, sea levels surging; these are seen as physical aspects of the natural environment that humanity will overcome.
Sure, human ingenuity might be able to mitigate some of the external damage done by rising sea levels or agricultural instability. But climate change offers a variety of threats to our global public health. Scientists predict the side effects of climate change to be dangerous and deadly storms, droughts and starvation, an increased spread of water and mosquito-borne illnesses, among others.
And as it turns out, climate change might even get its dirty little hands on something else: diabetes.
A team of researchers recently published a study in BMJ Open Diabetes Research & Care, which found that the rate of diabetes cases in the United States increased alongside increasing average temperatures. In fact, they calculated that a 1-degree C (or a 1.8-degree F) increase in temperature could cause up to 100,000 more cases of Type-2 diabetes per year in the United States.
To begin, let’s talk a little about what diabetes stems from. Diabetes, which impairs the body’s ability to produce insulin and therefore regulate blood sugar, has a few known causes. Obesity and a sedentary lifestyle are the big ones. Genetics and racial background also play a role. Until this study, no one had ever considered the atmosphere as a risk factor; these researchers were up for the task.
The scientists first compared U.S. data on average temperature recordings across every state with data on the incidences of Type-2 diabetes in every state. They found that with every 1-degree C increase in temperature, there was a 4 percent increase in diabetes cases.
When they completed the same analysis with global data, they found a similar trend. With every 1-degree C increase in temperature, there was a 0.17 percent increase in diabetes cases.
These percentages are small, but perhaps these scientists onto something major. What could explain this finding?
There’s something we have called brown adipose fat tissue, or brown fat. In essence, it is fat that has the main purpose of burning other fat in order to keep us warm (doesn’t that sound wonderful?). But as you might have guessed, this sort of mechanism is only activated when it is needed, and a rise in temperatures could slowly eliminate the brown fat’s job. This slow in metabolism may eventually lead to insulin resistance, and therefore more cases of diabetes.
Researchers hypothesize that this could be the connection between climate and diabetes cases. And this idea matches up with other studies that suggest exposure to colder temperatures as a treatment for regulating the metabolism of diabetics.
While interesting, these conclusions aren’t 100 percent guaranteed just yet. Remember: Association does not imply causation. In other words, the number of Starbucks most likely also increased from 1996 and 2009, and that certainly isn’t caused by an increase in temperature. So just because cases of diabetes are increasing as temperatures also rise, that doesn’t imply they are fully related. Societal and economic changes in that 13-year span undoubtedly lead to changes in eating habits or personal health care. More research needs to be done to understand the larger scope of changing public health and its link to the changing environment before drawing larger conclusions.
Regardless of the unsettled results of the brown fat hypothesis, climate change undoubtedly poses serious threats for nutrition, which may indirectly influence the number of cases of Type-2 diabetes. Think about it. Climate change affects the health and resilience of agriculture, which includes our stock of fresh fruits and vegetables. With a decreased availability of these nutritious foods, it is likely that rates of obesity (and thus, diabetes) will increase.
In that sense, the research does spark some important thinking when it comes to the impacts of climate change.
Climate change isn't just Earth science, and it isn't just medical science. It is a global public health issue and encapsulates just about everything our global society does. Biology and business interests, sociology and shopping habits — they all play a role in the same growing problem, but also the solution. Every type of scientist and every type of citizen need to work as an interconnected whole to get and stay ahead of the side effects.
Combating climate change and protecting our public health calls for all hands on deck.