Teen obesity and diabetes may weaken lifelong bone strength

Obesity and type 2 diabetes in adolescence can interfere with bone development, potentially increasing the risk of fractures and osteoporosis later in life, according to a study being presented Monday at ENDO 2025, the Endocrine Society's annual meeting in San Francisco, Calif.

The teen years are the most critical for building lifelong bone strength, according to lead researcher Fida Bacha, M.D., of Baylor College of Medicine in Houston, Texas. "While adults with type 2 diabetes are known to have increased risk of fractures, this has not been investigated in youth with type 2 diabetes," Bacha said. "We wanted to understand how childhood obesity and early type 2 diabetes affect bone health as children grow."

The researchers followed 48 teenagers for a year, including 26 girls, with an average age of 15.5 years. Of these, 27% had normal weight, 31% were classified overweight with normal blood sugar, and 42% had overweight with impaired blood sugar control, including prediabetes (4 teens) or type 2 diabetes (16 teens).

The researchers measured the teens' body fat, fitness, blood sugar and insulin levels. Their bone structure and strength in the lower leg (tibia) and forearm (radius) was measured using high-resolution imaging.

The study found that teens with obesity, and especially those with type 2 diabetes, showed less improvement in bone strength and quality over time compared to their peers who were of normal weight. This was true for both the leg and arm bones. Higher insulin levels (a sign of insulin resistance) seemed to contribute to less increase in bone strength. Insulin resistance is a condition where the body's cells do not respond effectively to insulin, leading to elevated blood sugar levels and increasing the risk of type 2 diabetes.

Obesity and early type 2 diabetes in adolescence don't just affect weight or blood sugar-they can quietly interfere with bone development during the most critical years for building lifelong bone strength. That means teens with these health issues may face a greater risk of fractures and osteoporosis as they get older."

Fida Bacha, M.D., Baylor College of Medicine in Houston, Texas