
New research shows that older adults who feel socially isolated may be more likely to develop diabetes and struggle with managing their blood sugar.
The findings were presented at ENDO 2025, the Endocrine Society’s annual meeting in San Francisco, and highlight how loneliness can have serious effects on physical health.
Dr. Samiya Khan, the study’s lead researcher from the Keck School of Medicine at the University of Southern California, explained that since the COVID-19 pandemic, more attention has been paid to the health risks of social isolation.
This study adds to the growing evidence that loneliness isn’t just an emotional issue—it’s also a medical one.
Khan and her team used data from the National Health and Nutrition Examination Survey (NHANES), a large, ongoing study that represents the health of people across the United States.
They focused on survey data collected from 2003 to 2008, which included health information from 3,833 adults between the ages of 60 and 84. These participants represented about 38 million older Americans.
After carefully analyzing the data and adjusting for other risk factors, the researchers found a strong link between social isolation and diabetes. Older adults who were socially isolated were 34% more likely to have diabetes than those who were more socially connected.
Even more striking, they were 75% more likely to have poor control of their blood sugar levels.
This means that not only are lonely older adults more likely to develop diabetes, but they also face more difficulty keeping their condition under control. High blood sugar levels over time can lead to serious complications such as heart disease, vision loss, and kidney damage.
Dr. Khan emphasized that this is one of the first studies to show this connection using a nationally representative sample of older Americans, which means the results reflect the broader population. With the number of older adults rising rapidly both in the U.S. and around the world, and with many of them living alone or feeling isolated, the findings are especially timely.
Khan believes doctors should start paying closer attention to their older patients’ social lives. Simple questions about loneliness or isolation could help identify people at greater risk of diabetes.
“Strong social connections matter—not just for mental health but also for managing chronic diseases like diabetes,” she said.