Excellent review, thank you. I was part of the PHS many years ago. I currently take two specific vitamins as I have Crohn’s disease and am deficient in them . I take them because a) my physicians have advised me to with my condition and b) my blood levels without them are low. I am under no illusion that taking them will make me live longer or prevent cancer or CV disease. But I am also no longer a member of this most widely studied group of patients: “ otherwise healthy.”