@KoiwiGal - In fact, the average person exceeds the daily recommended amount of chromium needed so I don't think it should be an issue for most people. It's found in quite a few common foods, including broccoli, dark chocolate, grape juice and red wine.
It has been found to help balance out insulin levels though and they really don't understand how it works or how much a person should have. The recommended daily amount is probably quite conservative.
As long as people keep to the limit suggested by the bottle of supplements I don't see the harm in it.