Whey protein powder isolate is one of the key active ingredients in the GNC Lean Shakes, and its purpose is appetite suppression. This whey protein has only a small amount of fat from animal sources, and provides almost 90% more protein than other hydrolysates. Hydrolysates are proteins that have been broken down for better absorption by the muscles. This protein isolate has been shown by many studies to efficiently build muscle mass and cause the body to feel full with very little foods, according to research published in Nutrition & Metabolism and other medical journals. 
I have been using this product for, 4 months now? I started off at 271 pounds , This is AFTER loosing 150 pounds in 2 years. I had hit a dead end and wasnt able to loose more then 2 pounds a month, I wanted to give up trying. My husband took me to GNC and we picked this product up. Well I am happy to say in 4 months I am back to shedding the weight ! I currently clock in at 215 pounds and am BEYOND happy with this product. The only issue I have with it is the size of some of the pills themselves but I have no complaint on the effects of this! BUT I do encourage those wanting to try this product to EAT something before taking them. The product works best when applied with a healthy diet and an active work out. There is NO such thing as a active pill that makes you loose weight without a work out.
Check out GNC’s pre-packed vitamins and supplements, specifically aimed at wellness and performance. Cleansing regimens include Nature’s Secret Super Cleanse tablets for digestion and standardized milk thistle, for liver cleansing. Herbal and natural remedies include red yeast rice and Royal Jelly bee pollen. You can even find joint and hip health supplements for your dog, and skin and coat essential supplements for your cat. Free two-day shipping on most orders sweetens the deal at GNC, as do GNC promotional discount codes.