A new study reveals Maine has the highest incidence of type 1 diabetes in the US, highlighting regional disparities and the growing need for specialised care as the disease continues to increase nationwide.
Maine has emerged as the country’s highest-incidence state for type 1 diabetes, according to new state-by-state analysis published in JAMA Network Open, even as the disease remains far less common than type 2 diabetes. The study found 27.4 new cases per 100,000 people in Maine, slightly above Vermont’s rate and narrowly ahead of West Virginia’s. New Hampshire and Kentucky also ranked among the states with the highest incidence, while Hawaii, New Mexico and California posted the lowest figures.
The findings add to a broader picture of a condition that is rising steadily in the US. A separate preprint study estimates that 2.07 million Americans were living with type 1 diabetes in 2024, with the total expected to increase by about 10% by 2033. That research also found more than 60,000 new diagnoses each year, with adults now accounting for roughly half of all new cases, most often among people aged 45 to 64.
Unlike type 2 diabetes, which is linked to the body’s reduced response to insulin, type 1 diabetes occurs when the immune system destroys the pancreas cells that make the hormone. Scientists still do not know exactly why the disease develops, but research has pointed to a mix of genetic susceptibility, infection and other environmental factors. The JAMA Network Open authors did not try to explain why some states had higher incidence than others, but they did say their results underline the need for more paediatric endocrinologists across the country.
Demographic patterns may offer part of the context. The report noted that more than 70% of type 1 diabetes cases have been diagnosed in White adults, with lower shares among Hispanic, Black and Asian populations. Maine, West Virginia and Vermont have some of the nation’s highest proportions of White adults, while Hawaii and California have much lower shares. Researchers have suggested that genetic variants linked to autoimmune disease, including HLA-DR3 and HLA-DR4, may help explain some of the disparity, although the evidence is not conclusive.
Other theories remain under investigation. Studies have explored whether enteroviruses, reduced early-life exposure to microbes, vitamin D deficiency, obesity-related insulin resistance and environmental chemicals may contribute to risk in genetically vulnerable people. Public health data from the CDC and the American Diabetes Association continue to show substantial state-level differences in diabetes burden more broadly, reinforcing the challenge of tailoring prevention and specialist care to local needs.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
