GNC has come a long way from its roots as a tiny health store founded in Pittsburgh, Pennsylvania, in 1935. What was once a single storefront specializing in yogurt and "healthy sandwiches" has blossomed tremendously over the last seven decades, and GNC now operates more than 4,800 locations across the United States. In addition to carrying a plethora of products from brands such as Optimum Nutrition and BSN, GNC stores also carry their own line of premium products, known as "Pro Performance."