Ask an Endo: Can a person with type 1 become type 2

Blog, Wellness

Question: Can a person diagnosed with type 2 diabetes convert to type 1 diabetes?


Dr. Richard Jackson:  The quick answer is no, but let’s look a little at why many people have this question. Type 2 diabetes is the most common type, comprising over 90% of all people with diabetes. At onset, people with type 2 diabetes can be treated very well with oral medicines (along with attention to physical activity and food) while people with type 1 diabetes are usually treated with insulin right from the beginning. These facts have led to the common thought that people with type 1 diabetes take insulin, while people with type 2 diabetes do not. However, as time goes by, people with type 2 diabetes make less and less of their own insulin. This is part of the type 2 diabetes process. Over time, their own insulin will not be enough to control their A1C, and they will need to take insulin, with a pen or other device, in order to keep their A1C in their target range. This doesn’t mean that their diabetes changed from type 2 to type 1, it just means that the treatment for their type 2 diabetes changed. It is important to remember that it is not your treatment that determines how well your diabetes is going, but whether your numbers, such as your A1C, are in a safe range. Someone taking insulin with an A1C of 7.2% is doing much better than someone not taking insulin whose A1C is 8.6%.

One additional note. Type 1 diabetes is not very common, and estimates are that one in two hundred people may develop it during their lifetime. This means that, by chance, one out of two hundred people with type 2 diabetes will also “develop” type 1 diabetes during their lifetime. This just means that they might need to take insulin a little sooner than they expected


Dr. Richard Jackson is an Endocrinologist who worked for more than 30 years with the Joslin Diabetes Center in Boston, MA..