At age 67, I have been taking the Oh! Mino for a while now. I do believe that is helping me at least maintain my muscle mass, if not helping me put on a small amount of muscle. But as I said, I am at the far end of the spectrum, age wise, to be gaining a whole lot of muscle. It mixes up real well in water. It tastes great, and I believe it helps me get through my workouts, without running out of energy. So I will continue to take it, as long as I continue to workout. I believe it is extremely important to consume the essential amino acids, that we don't get much of in our everyday diet.