USN Pure Protein GF-1 is a popular protein blend which is now the UK's best selling protein blend.

Protein blends are growing more popular in recent years thanks to research which has shown them that a blend of whey and milk enhances muscle protein synthesis more than whey protein or milk protein taken alone. 

Whey, and Milk Promote Muscle Growth

Pure Protein GF-1 employs a mix of three main proteins.

Whey protein is well established as a favourite among athletes because of its rapid dispersal after ingestion to your muscles as well as its high anabolic potency. Being rich in BCAA's it drives muscle recovery and growth better than other proteins.

Milk protein is ideal for use at night where its slow absorption helps to provide a continuous stream of amino acids to feed your muscles and help prevent your body from breaking down its own muscles for energy (a big risk at night when you are not eating any carbohydrates to supply the body quick energy). The choice of milk protein in Pure Protein GF-1 will be queried by some as calcium caseinate is not as easy to digest or as low in fat and carbs as micellar casein but on the flip side it benefits from being even slower to digest which in the context of a protein blend like this helps to offset the benefits of micellar casein.

Soy - Hero or Villain?

There is one more protein source in Pure Protein GF-1 which has attracted more negative commentary than just about any other protein source and instantly rules out Pure Protein GF-1 as a potential choice for many people - soy protein. 

Soy protein is very high in protein content and compared to other vegan protein sources richer in amino acid content. Soy has something of a bad reputation among bodybuilders but as our article on soy's impact on testosterone levels shows such worries are overstated and ignore the fact that subjects consuming soy and whey as a protein blend experienced greater increases in testosterone than a whey only group.

Our Verdict

Pure Protein IGF-1 gets good feedback from users for its taste while the range of flavours is impressive. Although we personally would prefer a blend such as Trutein for having superior protein sources and taste, Pure Protein IGF-1 definitely has an established fanbase.