Well that's a very loaded, confrontational question. It only causes the extreme side effects in rare cases, and it as long as you don't go drinking straight from the fondue fountain at a Leper's Anonymous meeting you probably won't get sick too often. It binds to Tumor Necrosis Factor Alpha, a cytokine, and prevents it from attaching itself to cells and triggering cellular processes associated with apoptosis, programmed cellular suicide. This is one of the root causes of inflammation in the human body. So it stops your inflammation by blocking one of the most important pillars of the sustained inflammatory response.