A shift in fat distribution from visceral (the internal abdominal area) to subcutaneous (under the skin) could be the reason the insulin sensitizer Actos (pioglitazone) helps to lower blood-glucose levels in people with insulin resistance.
Researchers from the University of Texas studied nine people with type 2 diabetes who took Actos for 16 weeks.
Despite an average weight gain of nearly 7 pounds and an increase in total fat mass during that time, fasting blood-glucose levels fell from an average of 179 mg/dl to 140 mg/dl, and A1C levels dropped from 8.6% to 7.2%. Fat distribution was evaluated with magnetic resonance imaging (MRI), which showed a decreased ratio of visceral to subcutaneous fat during the study.
—Journal of Clinical Endocrinology & Metabolism, June 2002