Coffee has been linked to a lower risk of Parkinson’s, which is a neurological disease that can cause tremors, balance problems, and mobility issues. In one 2000 study in the Journal of the American Medical Association, researchers looked at 30 years of data from over 8,000 Japanese-American men in Hawaii. They found that the more daily coffee they drank (up to 28 ounces, or three to four cups), the lower their risk of Parkinson’s compared with those who drank little or none. (The same seemed to be true of caffeine-containing beverages in general, so the theory is that the caffeine may be responsible.) There is so much research on this that the amount of evidence for the link is "substantial," according to a 2017 review, but still "not conclusive," so do with that what you will.