I wouldn't woory too much about the coffee having any negative impact on joint health. Of more concern should be your water intake. I'm sure you've heard it many times before but it really is important to drink at least 8-10 glasses of water per day. Your body needs it to help flush out toxins and to build strong muscle tissue that helps to support your joints. You may also want to consider taking a good natural joint supplement as well to help ensure that your body gets the nutrients it needs to build and maintain strong joints.