A recently published study has shed new light on Type 1 diabetes, offering a potential path to new treatment approaches for the disease, which plagues an estimated 9.5 million people worldwide. The research is not the end, but rather the beginning of work that lies ahead in the quest to understand the mysteries of diabetes, said Dana Dabelea, PhD, director of the Lifecourse Epidemiology of Adiposity & Diabetes (LEAD) Center at the Colorado School of Public Health.
Dabelea contributed to the UK National Institute of Health and Care Research-funded study, which appeared in the September 2025 issue of The Lancet. Researchers studied more than 1,000 children and young adults in the Sub-Saharan countries of Cameroon, Uganda, and South Africa who suffered from insulin deficiency, a hallmark of Type 1 diabetes.
Type 1 diabetes most often occurs when the body produces autoantibodies that attack and destroy cells that produce insulin, the hormone that regulates blood sugar. However, the Type 1 diabetes in about two-thirds of the young people studied in Africa did not seem to be caused by autoantibodies or by genetics related to autoimmunity. The effect was the same – they still needed insulin to live – but the cause was not.
Research discovery affects Black people in the United States
This new sub-type of Type 1 diabetes is not confined to Sub-Saharan Africa, noted Dabelea, who contributed data from the SEARCH for Diabetes in Youth study to the research. The national, multi-center SEARCH study, a quarter-century old, holds a wealth of information on some 20,000 young people with diabetes. It turned out that about 15% of those in the database with “Black ancestry” also had the apparently non-autoimmune form of Type 1 diabetes.
The finding shows that the new sub-type of Type 1 diabetes “is not unique to Sub-Saharan African countries,” Dabelea said. But she noted the wide difference in the proportions of young people in these countries and the United States is a question for further research.
“What does that mean and why?” Dabelea said. The issue is not only why the proportion of those in Sub-Saharan Africa with the “atypical” form of Type 1 diabetes is higher than those in the U.S., but also the reverse, she explained. Why do more people in the U.S. have the “typical” autoimmune form of the disease than those in Africa?
“Perhaps the ‘typical’ autoimmune form of the disease is more aggressive, and people in Africa with this form die more than those with the atypical form,” Dabelea said. “That’s one potential explanation.”
Research poses more questions about Type 1 diabetes
But it’s hardly the only one, she added. “Diabetes” is a single word that disguises the many factors that contribute to it, including genetics, the environment, and interactions between the two.
“What’s possible is that the genetic predisposition to Type 1 diabetes is different between countries, even among populations that are ancestrally the same,” Dabelea said. “The interactions with viruses and things that trigger autoimmunity may also be different. That would result in different proportions of different types of diabetes.”
Dabelea added a third possibility: differences in genetics and environmental exposures in the United States and Sub-Saharan Africa may, in turn, change the antibodies responsible for the autoimmune form of Type 1 diabetes in these two parts of the world.
“Maybe we have not measured the antibodies in the African population that are responsible for the autoimmune form of the disease,” she said. “Therefore, the form appears to be non-autoimmune, but that’s because we haven’t discovered the most important autoantibody yet in these populations.”
Many factors that may influence Type 1 diabetes remain unexplored
Looming over the new research is the question of access to health care, Dabelea said. The multinational TEDDY (The Environmental Determinants of Diabetes in the Young) study has pointed to important differences in environmental exposures that may trigger Type 1 diabetes, even in the developed countries that participated, Dabelea said. These include diets of mothers and infants, exposure to viruses, access to vaccines, and other factors.
“I would imagine that these differences are even more pronounced between the United States and Sub-Saharan Africa,” Dabelea said.
In short, Type 1 diabetes may be a well-known term, but that doesn’t mean it’s well understood, Dabelea said. The research in Sub-Saharan Africa underscores that point.
“We don’t yet know all the factors that are responsible for an autoimmune reaction that leads to Type 1 diabetes,” she said.
A call for follow-up research
Ultimately, the new research raises these and many other questions, but few answers for patients, parents, and clinicians, Dabelea said – at least for now. The Lancet study needs follow-up, she said, to understand the causes of and risk factors for this new form of Type 1 diabetes, as the TEDDY study is and has been doing with the autoimmune form of the disease. That will take time.
“This type of research cannot be done easily in a month or six months,” Dabelea said, adding that hard work is necessary to develop registries and longitudinal studies that establish the burden and course of various forms of Type 1 diabetes in Africa and around the world and spur governments to make investments in combating it.
The encouraging news is that long-term commitments to research have yielded victories in the broad battle against diabetes, Dabelea pointed out. The most visible is the widespread adoption and effectiveness of GLP-1 drugs to treat Type 2 diabetes, which is caused by the body resisting insulin.
In addition, research into MODY (maturity onset diabetes of the young), which is caused by a single gene defect, led to targeted treatment with drugs called sulfonylureas that help the pancreas produce more insulin, Dabelea said.
“These kids don’t need insulin and they have lower rates of complications, but the entire process took years and years of research,” she said. “I suspect this might need to happen with this new form of diabetes discovered in Africa. It just won’t happen fast.”
However, she emphasized that the payoffs from such research could be profound.
“The more we know about the mechanisms leading to various subtypes of this disease, the better we will be to develop novel drugs and identify the best therapeutic options,” Dabelea said. “Once we have them, access to those therapies for populations in our country and throughout the world is the next big thing.”
