Chromium supplementation has recently been advocated for preventing dietary deficiency, reducing body fat, and increasing muscular mass and strength [1]. We describe a patient who developed renal failure after using over-the-counter, oral chromium picolinate, 600 µg daily for 6 weeks, for weight reduction.

A 49-year-old female nurse presented to our office for evaluation of renal insufficiency. Test results had shown normal renal function 2 years earlier but now showed a blood urea nitrogen level of 74 mg/dL and a creatinine level of 5.9 mg/dL. Urinalysis showed a protein level of 30 mg/dL, trace amounts of blood, a leukocyte count of 0 to 1 cells per high-power field, and an erythrocyte count of 1 to 2 cells per high-power field. The 24-hour urine protein level was 782 mg. The patient admitted to having ingested chromium picolinate 5 months earlier. From the time of her last normal serum creatinine level until presentation, the only other medications she received were antihypertensive agents.

A renal biopsy done on 25 January 1996 showed results consistent with severe chronic active interstitial nephritis. Prednisone, 60 mg, was administered; after 2 months of therapy, her serum creatinine level decreased to 3.8 mg/dL.

Chromium has been proposed as an essential trace element that is a cofactor for insulin and enhances the various actions of insulin, including metabolism of glucose, protein, and fat [2]. Chromium deficiency remains hypothetical, given that objective signs of a deficiency syndrome have not been observed in the general population [3].

Chromium picolinate has recently been synthesized to increase the bioavailability of chromium in dietary supplements [4]. Our patient ingested chromium picolinate at levels 12 to 45 times the usual intake of dietary chromium and 3 times the recommended doses for dietary supplementation.

The renal biopsy findings support a diagnosis of chromium-induced nephrotoxicity, given that the renal histologic picture, although nonspecific, is consistent with chronic interstitial nephritis from heavy-metal exposure.

The recent over-the-counter availability of chromium picolinate and the aggressive advertising campaign to promote its sale in drug and health food stores pose the threat of more widespread adverse effects to which the medical community and general population should be alerted. Warning labels and the advisability of increased regulation of this drug are matters that must be addressed by the Food and Drug Administration.