Chromium is a type of metal known as an essential trace element because a very small amount of it is important for human health. One of the biggest health concerns facing men is the onset of Type 2 diabetes, so any supplement that can help beat back the threat of the disease has a definite place on this list.
The American Journal of Clinical Nutrition reported that chromium supplements help normalize blood sugar levels, while chromium deficiency can cause glucose intolerance that leads to Type 2 diabetes. The NIH also acknowledges that taking chromium may lower insulin levels. This could help improve the function of insulin in people with Type 2 diabetes, though this should be coordinated carefully with a physician.
Unfortunately, the evidence is less convincing for chromium supplements as a way to combat obesity and promote weight loss. And while many people use chromium as a supplement for body conditioning, it doesn't seem to have much effect in this realm, either.
That said, it's possible that prevention and management of diabetes make it a good idea to take at least 35 mcg (micrograms) a day. Look for "chromium picolinate" on the label, as studies have found this to be the most effective form of chromium.