On Apr 13, we issued an updated research report on Pittsburgh, PA-based GNC Holdings Inc. GNC. The company is a leading global specialty retailer of products for health and wellness, including vitamins, minerals, and herbal supplement, sports nutrition and diet.Retail, the largest segment at GNC Holdings, serves as the biggest contributor to its growth trajectory. During the company’s last reported fourth quarter of 2015, the company witnessed improvement in domestic retail same-store sales in all location types, including malls and strips. Moreover, strip same-store sales grew 4% in the quarter.On the other hand, while malls were negative in the quarter, the same improved through 2015 and continues to create significant value for shareholders.Further, the company’s overseas business continues to be a key growth driver. During the reported quarter, the company’s international sales increased 9.6% buoyed by an increase in wholesale revenues. Additionally, management opened 55 international franchise locations. Going forward, GNC Holdings plans to open 50 net new franchise locations in its international market.The company also holds a strong cash balance position. During 2015, GNC Holdings generated operating cash flow of over $50.7 million, resulting in a 31.6% rise in free cash flow. Per management, the upside in the free cash flow reflected an improvement in working capital and lower capital expenditures.Further, during the fourth-quarter earnings release, GNC Holdings declared a cash dividend of $0.20 per share of its common stock for the first quarter of 2016, representing an 11% increase.On the flip side, GNC Holdings continues to face tough competition in the U.S. nutritional supplements retail industry, which is large and highly fragmented. Management fears that such stiff competition might hamper GNC Holdings’ growth prospects.Further, the company’s inability to act in response to changing customer trends and preferences may affect customer relationships and product sales. Also, failure to comply with Federal Trade Commission regulations may dampen its business prospects.GNC Holdings currently carries a Zacks Rank #2 (Buy).Other Key Picks Other favorably ranked stocks in the medical sector are Orthofix International N.V. OFIX, LeMaitre Vascular, Inc. LMAT and Baxter International Inc. BAX. While Orthofix sports a Zacks Rank #1 (Strong Buy), LeMaitre Vascular and Baxter hold a Zacks Rank #2.Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report BAXTER INTL (BAX): Free Stock Analysis Report ORTHOFIX INTL (OFIX): Free Stock Analysis Report LEMAITRE VASCLR (LMAT): Free Stock Analysis Report GNC HOLDINGS (GNC): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research