The invention provides compositions and methods to treat prediabetes. In particular, the invention has discovered that particular combinations of diverse types of antioxidants have synergistic and surprising effects for use against prediabetes. The diverse types of antioxidants include: antioxidants that comprise stabilizing heteroatoms; antioxidants with conjugated segments of alternating single and double bonds; antioxidants with disulfides; and antioxidants with phenolic groups. In particularly useful embodiments one or more of the antioxidants that comprise stabilizing heteroatoms have pro-oxidant effects, e.g., in the liver.