OptiMSM™. Connective Tissue & Joint Support. 100% Pure. OptiMSM™ is the original patented licensed and tested MSM backed by over ten years of research. It is the form used by Dr. Stanley W. Jacob M.D. in his work with over 13000 patients. MSM (Methylsulfonylmethane) is a naturally occurring organic sulfur compound that is found in the body's muscles nerves tissue skin hair bones and joints. Dietary supplementation of MSM supports the creation of new cells and connective tissue and helps promote healthy skin hair muscles and flexible joints.