 By 2009, about 15% of Americans had tried taking dietary supplements for weight loss, and Hydroxycut was the biggest seller, with about a million units sold each year.However, Hydroxycut formulations contained several substances with potential to harm the liver such as hydroxycitric acid.Scientific evidence of serious side effects from Hydroxycut products accumulated, including liver failure (requiring liver transplantation in some cases), rhabdomyolysis, and at least one death, of a 19-year-old man who used the product.