People with type 1 diabetes are living longer. Survival rates have increased significantly over the past 20 years and as a result, the overall health of people with this condition has changed. Obesity, once rare in patients with type 1 diabetes, now affects 37 percent of this population in the U.S. Unfortunately, care for overweight or obese people with diabetes has been slow to factor in this development.

The rates of overweight and obesity in people with type 1 diabetes are basically the same as rates in the general population. Researchers at Johns Hopkins University found two-thirds of those with type 1 diabetes were overweight or obese, and they were less likely than those with type 2 diabetes to receive recommendations about lifestyle changes from their doctor. And they were also the least likely group to increase physical activity and reduce caloric intake.

The link between overweight and obesity and poor health outcomes is of even greater concern in those with type 1 diabetes because they are already at increased risk.

Being overweight or obese increases the risk of poor health outcomes — like heart disease, stroke, kidney disease and cancer — in people who don’t have diabetes, researcher Michael Fang told TheDoctor. But because they are already at an increased risk, the poor health outcomes linked to overweight and obesity are of even greater concern in people with type 1 diabetes. “You don’t want to add additional risk factors, such as obesity, if you can help it.”

The classic description of someone with type 1 diabetes is young and lean; that's why the high rate of obesity and overweight in those with type 1 diabetes may come as a surprise to providers and public health researchers, said Fang, an assistant professor of epidemiology at Johns Hopkins.

Researchers analyzed five years of data — between 2016 and 2021— from almost 130,000 participants in the National Health Interview Survey, a representative sample of the U.S. population, for the study. Participants’ body mass index (BMI) was calculated using self-reported height and weight, and they were placed into one of three groups based on their BMI: normal weight (BMI less than 25 kg/m2), overweight (BMI of 25 to less than 30 kg/m2) and obese (BMI of 30 kg/m2 or greater).

Sixty-four percent of the study participants without diabetes were overweight or obese, compared to 62 percent of those with type 1 diabetes and 86 percent of those with type 2 diabetes. In 2016, 2017 and 2020, participants reported whether or not their doctor had recommended lifestyle changes, such as getting more exercise or eating fewer calories or less fat, in the past year. They also reported whether they were following those recommendations.

The team found that “only about half of these patients received lifestyle recommendations from providers or engaged in lifestyle modification.” They also noted that, “persons with type 1 diabetes were least likely to increase physical activity or reduce caloric intake to manage overweight or obesity.” They believe randomized clinical trials are needed to better understand the best way to promote safe and effective weight management in those with type 1 diabetes.

Exercise and dieting can be tricky for those with type 1 diabetes who will need to adjust their insulin dose to keep blood sugar at safe levels. If you have type 1 diabetes, consult with your doctor about how to do this and monitor your A1C.

The study is published in Annals of Internal Medicine.