Pittsburgh-based GNC opened in 1935, and today offers many ingredients—vitamins, supplements, minerals, herbs, sports nutrition and more—for a healthy diet, as well as a variety of GNC deals for a healthy budget, too. Deal of the day; buy one, get one free offers; clearance merchandise—all great ways to save. Sign up for email alerts and you’ll get a discount just for joining, plus receive GNC coupons and special promotions.