Since MSM is so ubiquitous and can be found in almost all raw foods, it is considered safe for consumption and for use in many other applications. While it is recognized as safe, be sure to check with your doctor before taking MSM, especially if you are allergic to sulfa drugs (sulfonamide). It has been noted, however, that since MSM is chemically different than sulfa and occurs naturally in the body and in most raw foods, a reaction is unlikely. If you are pregnant or breastfeeding, it is highly recommended to only take supplements as instructed by a physician. In some cases, sulfur can make skin more sensitive to the sun.
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Kim, L.S., Axelrod, L.J., Howard, P., Buratovich, N., & Waters, R.F. (20 ). Efficacy of methylsulfonylmethane (MSM) in osteoarthritis pain of the knee: A pilot clinical trial. Osteoarthritis and Cartilage, 14(3), 286-294.
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