Insulin gets a bad rap: Needles, weight gain, and low blood glucose (hypoglycemia) loom large as reasons people avoid this potentially lifesaving medication. But a new study out of China has found evidence that, in patients with newly diagnosed type 2 diabetes, intensive treatment with insulin actually turned back the course of the disease more often than oral medications did.

Previous studies had found that early intensive insulin therapy could preserve the function of pancreatic beta cells—the ones that make insulin—which diminishes over time in type 2. But it was unclear whether insulin itself was responsible for this benefit or if it was the result of lowering blood glucose. This study demonstrates that insulin has benefits above simply treating high glucose.

The 382 patients, aged 25 to 70, were grouped into one of three segments: One group used insulin pumps, another took bedtime and pre-mealtime insulin injections, and the third used oral meds (a sulfonylurea, metformin, or a combination of the two). The participants stayed on their medication regimen until they achieved normal blood glucose levels, and then for two weeks afterwards. They were then taken off the treatment.

After one year, half of the insulin group—compared with only a quarter of the oral agent group—had maintained normal blood glucose levels using only diet and exercise. Yet, the authors note, “any kind of early intensive glycemic control”—meaning using either insulin or pills to control blood glucose—“could rescue beta-cell function and induce long-term glycemic remission.”

In addition, insulin therapy had done right by the beta cells, which were healthier in the insulin groups, especially the pumpers, than in the group that had taken oral agents. Supplemental insulin, it seems, may give the beta cells a much needed break.

This study was published in the May 24, 2008, issue of The Lancet.