Wheat bran is made from the outer shell (the husk, I'd guess you call it) of the wheat plant. It's got a ton of dietary fiber which is good stuff to have in your diet. Fiber aids digestion and bowel movement. It has also been shown to help prevent certain types of diseases, especially cancer of the colon and stomach. Wheat bran is used as a food supplement as well as a medical supplement.
Need more information? Newspaper archives are one of the best online research tools.