Researchers from Yale University School of Medicine in New Haven, Connecticut, recruited 43 overweight or obese type 2 diabetics with poorly controlled blood sugar who were taking, but not responding well to, oral anti-hyperglycemic drugs.
Participants took 2 mg of biotin plus 600 mcg of chromium picolinate per day or a placebo for four weeks. Researchers tested blood sugar control at the start and end of the study and found that those who had taken biotin and chromium picolinate had an average 9.7% decrease in blood sugar levels compared to the start of the study, while blood sugar levels in the placebo group increased an average of 5.1%. Blood fats (triglycerides) decreased 9.25 mg per deciliter of blood (mg/dL) in the biotin/chromium picolinate group while increasing 59.75 mg/dL in the placebo group.
Researchers also measured blood-fluid (serum) levels of fructosamine, a sign of poor blood sugar control and found that levels decreased 1.3 millimoles per liter of serum (mm/L) in the biotin/chromium group while increasing 0.7 mm/L for placebo. Participants reported no significant side effects. Doctors concluded that for people with poorly controlled diabetes, biotin combined with chromium picolinate may be an effective complementary therapy that may also help lower blood-fat levels.