Do you drink soy milk or consume soy protein powder as a part of your daily diet for muscle development? Soy milk has a substantial amount of protein in it and is lactose-free as opposed to cow’s milk. I was reading an article from a very popular website (which shall remain nameless for now) about how soy milk and soy protein is beneficial to the growth of muscle mass having little or no effect on a male’s testosterone level and I couldn’t disagree more about the information I read.

Even though soy milk is a good source of protein it contains phytoestrogens which are referred to as isoflavones that activates the body’s estrogen receptors. This could have a devastating effect on an athlete who is trying to gain muscle mass because the isoflavones increase the estrogen levels in the body which lowers the amount of testosterone that is needed for the development of muscle mass growth. Testosterone is the hormone responsible for a male’s level of strength and energy. There have been some disagreements on whether or not soy milk or soy protein decreases muscle mass. A number of clinical studies have resulted in evidence showing that soy milk and soy protein does lower testosterone levels in the body of males while other studies have shown tests to be inconclusive.

The reason there are some websites out there showing soy in a positive light for the growth of muscle mass is that the soy industry are backed by lobbyists. Lobbyists are a group of individuals that attempt to influence legislation on the behalf of a special interest in a certain industry. I’m highly confident that these advocates for the soy industry have a great influence (money) on certain health and fitness websites that will try to lead you on to believe that soy milk and soy protein has no negative effects on the testosterone levels in males. As far as I’m concerned, I strongly believe that soy will increase estrogen levels which automatically lowers testosterone in males which leads to a decrease in muscle mass.

For those of you who are not sure about the effects of soy or believe in the groups and individuals that claim soy is beneficial for the development of muscle mass growth, conduct a test on yourself by consuming soy protein powder or drinking soy milk. If you start to notice a decrease in your level of performance during your workout within the next couple of weeks, you will have answered your own question about soy having a negative effect on muscle development. Who knows, maybe there will be no change or reduction in your muscle growth (which I highly doubt), only time will tell.