@BowsacNoodle @sickburnbro I have a variety of immuno-related diseases (asthma, chronic rhinosinusitis, etc.), and Vitamin D supplementation (< 2000 IU per day) both smoothes their symptoms and increases the bodily energy that used to be wasted on net in taking care of them. Of course, it requires, to be effective, more than simple supplementation (exercise first).