An increasing overlap between type 1 diabetes and insulin resistance challenges traditional classifications, prompting a shift towards integrated management strategies to mitigate cardiovascular risks.
People with type 1 diabetes are usually told to think of their condition as a lack of insulin, while type 2 diabetes is framed as a problem of insulin resistance. In practice, though, those categories can blur. Diabetes Daily explains that some people with type 1 diabetes also develop marked insulin resistance, an unofficial pattern often called “double diabetes”. A 2024 review in Cardiovascular Diabetology says the concept is increasingly recognised because the overlap can complicate treatment and raise cardiovascular risk.
The term itself is not an official diagnosis, and diabetes specialists do not generally test for it in any single, standard way. Robert Gabbay of the Joslin Diabetes Center told Diabetes Daily that he is wary of the label, but said it is commonly used to describe type 1 diabetes accompanied by insulin resistance, often linked with obesity. Medical News Today and Abcam both describe the underlying distinction clearly: type 1 diabetes is driven by autoimmune destruction of insulin-producing beta cells, whereas type 2 diabetes involves resistance to insulin and, over time, declining beta-cell function.
Insulin resistance in type 1 diabetes can arise for many of the same reasons it does in type 2 diabetes. Diabetes Daily points to excess weight, especially abdominal weight gain, as well as inactivity, highly processed diets, stress, ageing, hormonal shifts and some medicines. The article also notes a difficult feedback loop: higher insulin doses can contribute to weight gain, which can then worsen resistance and drive the need for still more insulin. That does not mean insulin should be cut back on purpose; Gabbay warned that underdosing can lead to dangerous hyperglycaemia and diabetic ketoacidosis.
The warning signs are often indirect. A person who once had predictable glucose control may begin needing more insulin, adjusting insulin-to-carbohydrate ratios more often, or seeing persistently elevated blood sugars despite following their regimen. Diabetes Daily also lists rising A1C, worsening time-in-range, weight gain, high blood pressure, abnormal cholesterol, fatty liver disease and a family history of type 2 diabetes as possible clues. The article stresses that clinicians should also rule out technical problems such as pump failures, poor absorption, dosing mistakes, illness or medicines that can raise glucose.
The concern is not only harder day-to-day management. Diabetes Daily says insulin resistance in type 1 diabetes is associated with high blood pressure, lipid abnormalities, liver fat and a greater risk of cardiovascular disease. A meta-analysis of eight studies involving nearly 22,000 people with type 1 diabetes found that greater insulin resistance was linked with a higher risk of cardiovascular disease and death during follow-up. The 2024 Cardiovascular Diabetology review similarly highlights the need to recognise the overlap early because of its broader metabolic and vascular consequences.
Treatment usually means addressing insulin resistance alongside routine type 1 diabetes care. Diabetes Daily says physical activity, less sitting, and dietary changes that reduce refined carbohydrates can improve insulin sensitivity, while protein and fibre may help with fullness and weight control. Gabbay told the publication that some patients may also benefit from metformin or GLP-1 drugs, which are commonly used in type 2 diabetes and may reduce insulin needs, although GLP-1 medicines are not approved for type 1 diabetes. The article’s central message is that insulin resistance is a treatable part of diabetes care, not a sign of personal failure.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
