ok here the deal. My 16-year-old friend wants to start taking whey Protein, he wants to know if this is safe, if it is which would you recomend he wants the fast and slow release kind and it has to have enough L-Glutamine.

I would say that taking whey protein is totally safe, but I can't recomend a brand over the rest. But if it is 100% whey protein, I doubt you would go far wrong.

I am personally skeptical about "time release" products. It takes time for your body time to digest its nutrients...and that's usually good enough for me. As for the difference between brands, or qualities, I have been told that you usually get what you pay for. If you look at the break-down of amino acids on the side of the tub, you can see that a "cheaper" whey protein contains lower volumes/quantities. I have a tough time justifying the brands that cost double what other ones do, but the break-down indicates that you get half of what the others give you. I have been told that for Johnny regular workout dude (ie a non- competitive weight trainer) a cheaper version will suffice (correct me if I'm wrong anyone).
I can't see how taking any whey protein would be harmful to anyone unless they have allergies.
As for the L-Glutamine, there is only a small amount in even the most expensive, higher quality, proteins. Get an individual supplement. But on that note, get to know the purpose of taking any of this stuff in order to maximize the performance of these costly supplements.

Preach on. But, I would add that you want to find one that tastes at least bareable. I've chugged some before that made me hurl, seriously they did.
scott