My 17 year old wants protein shakes! Are they safe??

Look for a shake that's real simple, like whey protein. You'll see a lot of amino acids in it, those are the building blocks of protein and they usually list them, so don't get overwhelmed, depending on the brand where you live, etc.-they all start with L-. I agree with looking out for creatine, that just puts water into the muscles and puffs them up. He's too young for that, I can't remember the age recommendation but it sure isn't 17! Have him make up a shake, drink half of it 30 minutes before the workout and the other half 30 minutes after the workout. He needs it for fuel for workouts and for recovery for his muscles. If you have a local nutrition store, sometimes they have a knowledgeable staff, hopefully honest (I used to manage one) and will tell you what you need, express your concerns about your son. Sometimes they work on commission, so they will seem pushy-walk out the door then! If he's working out a lot, it's really important that he's eating a balanced diet or at least taking a multivitamin too!

I would be a little concerned if they have creatine in them, or testerone boosters, but just protein shouldn't be too big a deal. The only big worry with consuming a lot of protein that I can think of offhand is difficulty in digesting them, and possible damage to the kidneys. I would suggest talking to a doctor or nutritionist before your son starts using them. I have known a lot of athletes who got the push they needed to get over a plateau through the use of protein shakes, but, though protein itself is necessary in the diet, too much of a good thing can be bad.