Expiration dates.
So about two years ago my mother bought me a container of Tums. I originally started taking Tums for calcium since I don't drink milk. Ever. Now this might not have been the smartest approach to adding calcium in my diet, but it seemed like a good idea at the time. They were cheaper than vitamins (by the way: I have since switched to One-A-Day, so no worries). The other night I had heartburn. Really bad heartburn. Since I've been eating differently this entire summer (low fat, low cal, high protein, high fiber foods), I wasn't used to eating greasy foods. I just stopped eating them. However, I went to Sonic's with Stacey and Tony and little Munchkin the other day and the end result was not a pound gained, but heartburn. So I took a Tums. It worked. Nice. Love Tums. Just realized tonight, though, that the expiration date was last December. Whoops. Well, the stuff still works, and I still have half a bottle left. I see no reason to throw them away, really. So I think I'll just keep them.