MSM is sulfur, which is second only to water in your body chemistry. MSM supplements are only questionable if you do not use a reputable brand with Lingnisul, OptiMSM and TriMedica are some good examples.
What distinguishes a good brand from a poor brand is it's source. Poor quality brands have sulfur that is processed in countries with substandard water quality. Water is used in the crystallization of sulfur. You probably have heard the saying, don't drink the water, by travelers. That's because some countries do not filter impurities to the standards we're accustomed, and the result is bacteria left in the sulfur that makes us ill.
MSM is water soluble, and any excess your body does not use will be flushed from your body. It is safe, but you must drink water with each dosage and the higher the dosage, the more water you must consume, otherwise, your body will detoxify and you may have cold/flu like symptoms.
Sulfur is good for your entire body. It helps to fight the effects of aging.
Here is a good thread started by Poohbear, where I list other thread links to review and give a breakdown of how sulfur is used in the body.
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