My theory: people take more vitamins when their diet is crap. I know I do this. I'll eat a dinner of popcorn and ice cream and supplements sometimes. But when I eat fresh organic veggies and meat, I skip the supps and don't worry about it. Perhaps we "older" women are using our pills to justify a terrible diet. Maybe? Guess I better start taking my calcium, though.
Absolute risk increase (total mortality)
Arch Intern Med. 2011;171:1625-1633,1633-1634