Welcome to healthcaremagic.com. I am glad you are exercising, now on the whey protein like anything, you need to have this in moderation, remember the main side effect is development of kidney stones due to the high concentration of proteins. Always drink lots of water with it. Some people have reported constipation, bloating, gas and so forth, obvious individual results will vary another is osteoporosis after a long time. So please weight the personal risks to the benefits. I hope this helps you out, good luck.