Magnesium is critical to many functions in the body, including nerve function and muscle function. Around half of Americans consume less than the recommended amount of magnesium from food.
Research is sparse but many people believe that magnesium glycinate reduces anxiety and promotes better sleep, which in turn may help reduce tics in some people. Magnesium glycinate may also help relieve muscle tension, which some people experience from their motor tics.
Sources: Mayo Clinic, PubMed, Healthdirect Australia