Chromium Side Effects and Warnings

Safety Issues

Although the precise upper limit of safe chromium intake is not known, it is believed that chromium is safe when taken at a dosage of 50 mcg to 200 mcg daily. ¹ Side effects appear to be rare.

However, chromium is a heavy metal and might conceivably build up and cause problems if taken to excess. There is one report of kidney, liver, and bone marrow damage in a person who took 1,200 mcg to 2,400 mcg of chromium for several months; in another report, as little as 600 mcg for 6 weeks was enough to cause damage. ² Such problems appear to be quite rare, and it is possible that these individuals already had health problems that predisposed them to such a reaction. The risk of chromium toxicity is believed to be higher in individuals who already have liver or kidney disease. ³ Nonetheless, based on these reports, it’s possible that the dosage of chromium found most effective for individuals with type 2 diabetes—1,000 mcg daily—might present some health risks. For example, there is some evidence that if chromium is taken in high enough amounts, it may be converted from its original safe form (chromium 3) into a known carcinogen, chromium 6. ⁴ We advise seeking medical supervision before taking more than 200 mcg of chromium daily.

Also, keep in mind that if you have diabetes and chromium is effective, you may need to cut down your dosage of any medication you take for diabetes. ⁵ Medical supervision is advised.

There are also several concerns about the picolinate form of chromium in particular. Picolinate can alter levels of neurotransmitters. ⁶ This has led to concern among some experts that chromium picolinate might be harmful for individuals with depression , bipolar disease , or schizophrenia . ⁷ There has also been one report of a severe skin reaction caused by chromium picolinate. ⁸ Finally, there are also concerns, still fairly theoretical and uncertain, that chromium picolinate could cause adverse effects on DNA. ⁹ The maximum safe dosage of chromium for women who are pregnant or nursing and for individuals with severe liver or kidney disease has not been established.

Interactions You Should Know About

If you are taking

• You may need extra chromium if you are taking:
  • Calcium carbonate supplements
  • Antacids
  • You should also separate your chromium supplement and your doses of these substances by at least 2 hours, because they may interfere with chromium's absorption

• You may need extra chromium if you are taking:
  • Corticosteroids

• Seek medical supervision before taking chromium because you may need to reduce your dose of these medications:
  • Oral diabetes medications
  • Insulin

• Chromium supplementation may improve levels of HDL ("good") cholesterol if you are taking:
  • Beta-blockers