A new study adds to the evidence that diabetes makes bones fragile, but there’s also good news: Exercise can counteract the weakness if blood sugar is controlled.

Diabetes affects almost 30 million Americans and can cause serious health complications such as heart attack, stroke, and limb disability. But its effect on bone health is a lesser-known, but equally serious complication.

Previous research has found that diabetes increases bone fracture risk. University of Delaware scientists decided to study whether exercise could mitigate diabetes-related bone weakness.

Osteocytes, or bone cells, are critical to maintaining the tissue quality and integrity bone because they orchestrate its adaptation processes under mechanical cues such as exercise, the researchers said.

They suspected that diabetes could impair this response.

They found that exercise-induced bone formation was maintained in mildly diabetic mice at a similar level as non-diabetic controls, while the positive effects of exercise were nearly abolished in severely diabetic mice.

These results also showed the impact of good blood sugar management in programs designed to build up bone strength in people with diabetes, the researchers said of the study, which is published in the journal Bone.