From everything I have read you only need about 30mcg per day, those tablets have 250mcg and if you are taking 3 of them then you would be having 750mcg per day. New research suggests that chromium picolinate may cause damage to the body's cells, and there's no evidence that they can reduce cholesterol levels, aid in weight loss, or control diabetes.

Personally I wouldn't touch them.

From the MSDS (Material Safety Data Sheet)
I've just realised that, that MSDS was for "chromium picolinate", where as the ingredient in the tabs he gave me is "chromium polynicotinate". Which, as far as I can tell, is different. I could be wrong though, I don't know anything about herbal medication (or reading MSDS for that matter)