Nearly 60 years ago, chromium, as the trivalent ion, was proposed to be an essential element, but the results of new studies indicate that chromium currently can only be considered pharmacologically active and not an essential element. Chromium is a mineral that humans need in very small quantities. Good sources include broccoli, liver, and brewers' yeast. Taking chromium by mouth is effective for preventing chromium deficiency. It is also taken by mouth for depression, Turner's syndrome, polycystic ovary syndrome (PCOS), lowering "bad" cholesterol, raising "good" cholesterol in people taking heart medications called beta blockers, obesity, metabolic syndrome, heart attack, schizophrenia, bipolar disorder, binge eating disorder, and a disease called reactive hypoglycemia. Chromium has been marketed as an agent to reduce body mass and develop muscle; however, such marketing claims are no longer allowed in the United States because they are not supported by experiments. Trivalent chromium has also been proposed as a therapeutic agent to increase insulin sensitivity and affect lipid metabolism. Although effective in certain rodent models, beneficial effects in humans have not been unequivocally established.