protein

I was having this argument the other day with a buddy of mine at the gym who is also a supplement representative for one of the top companies online. He was saying that protein powder was a good idea for cutting because it won't add any calories to your daily number but it will boost your muscle...

I haven't taken protein powder in so long that I forgot how weird this stuff tasted. But this stuff really tastes weird because I drink it and it tastes like I'm drinking something metallic. has anyone experienced this and do you think that it means that my body is being poisoned

there are so many choices with whey protein I don't even know where to start. I see a lot of things that include grass-fed protein, I think that there's some with collagen, I think there's some that are whey isolate and Whey concentrate. How do I know which one to pick I'm not sure who to trust