Who would expect that raised postprandial (after-meal) blood sugars would be associated with a reduced risk of fractures? A Swedish study reported in the Journal of Clinical Endocrinology and Metabolism examined middle-aged adults enrolled in the Malmo Preventive Project. There were 22,000 men and 11,000 women; their average ages were 44 (men) and 50 (women), and they were followed for 19 years (men) and 15 years (women), respectively.

Raised 2-hour blood glucose levels were linked to reduced risks of multiple and osteoporosis-related fractures, independent of age, body mass index, and smoking. "Increased 2-hour glucose levels" were between 78 and 112 mg/dL (4.3 and 6.2 mmol/L) for men, and above 117 mg/dL (6.5 mmol/L) in women. Moreover, in women with results above 135 mg/dL (7.5 mmol/L) there were reduced numbers of osteoporotic fractures.

The average 2-hour blood sugar levels used here are not really very high; they were derived from classifying all the subjects into 4 classes, according to their blood sugars, and comparing the lowest-level group with the top, or the 2nd and 3rd. In a USA population the group levels would probably be quite a bit higher. Nevertheless, the finding that higher postprandial glucose levels may have a protective effect is intriguing, and quite the opposite of what one would expect, based on reports from type-1 (juvenile) diabetes. The mechanism of the effect is not yet known . . .