The investigators will perform body composition analysis by using a DEXA machine, liver fat measurement by using an MRI, and hyperinsulinemic euglycemic clamp procedures in 48 HIV infected, insulin-resistant/prediabetic subjects before and after 30 days of treatment with tauroursodeoxycholic acid or matching placebo. Biopsies of adipose tissue and skeletal muscle will be taken during fasting conditions and during insulin infusion, before and after treatment to measure markers of endoplasmic reticulum stress and thyroid hormone deiodinase.