A delicious shake that delivers at least 33g of protein per serving, along with other ingredients specifically chosen to support your weight-loss programme. What is Impact Diet Whey Protein? Impact Diet Whey is a whey protein powder that has been specially developed to provide a boost of protein1 without unnecessary carbs. We've also added extra glutamine, which naturally occurs in protein, which helps to build and repair new muscle1 — important when you’re looking to tone up. What’s more, this protein shake is also great for vegetarians, so you can enjoy the benefits of Impact Diet Whey whatever your lifestyle. What does Impact Diet Whey do? Impact Diet Whey is an excellent source of protein, which has been scientifically proven to support the growth and maintenance of muscle mass1.