Food Supplements. Fact or Fiction?

I saw this in a glossy magazine that I can't recall the name of but I cut it out. I thought it was interesting and I have not done any further research, so it may be based on good fact or a brief story sensation, based on rat research, not humans. "Chromium -  is a critical nutrient in blood-sugar regulation as it increases insulin's efficiency. If chromium levels are low, blood sugar levels may remain high. the good news is that in individuals where chromium is low, supplementing the diet with chromium has been demonstrated to lower overall bodyweight, increase lean body mass, improve glucose tolerance and decrease total cholesterol and triglyceride levels. High chromium foods include brewer's yeast, broccoli, whole grains (expecially barley), cereals, nuts, oysters, mushrooms, rhubarb and beer and wine. Broccoli tops the list as the highest known quantity of chromium. One analysis showed that 140g of broccoli contained 22 micrgrams of chromium, 10 times more than any other food."