PITTSBURGH — GNC Holdings' second-quarter net income rose nearly 8 percent as the nutritional supplement retailer sold more products and opened its first store in China as it expands internationally.

The results, released Thursday, beat Wall Street expectations. GNC's shares rose more than 8 percent.

GNC sells vitamins, herbal supplements and other health products. It has been rolling out a Gold Card loyalty program to all of its stores and its GNC.com website.

CEO Joe Fortunato said the rollout went smoothly and new products are performing above expectations.

The company also has been expanding internationally and it opened its first store in China, in Shanghai, during the quarter. It has opened 151 stores since last year's second quarter.

During the three months that ended June 30, GNC's net income rose to $71.7 million, or 73 cents per share. That compares with net income of $66.7 million, or 62 cents last year. Analysts expected 70 cents per share, according to FactSet.