Mae Zachary of Walnut Creek wanted to try a new diet, so she ordered a supply of meals from NutriSystem, but when it arrived, she found some of the packaged soup and chili looked way outdated.
"It had best by 1998, best by 1998! I was furious. I didn't even open the rest of the box," says says Zachary.
Mae called NutriSystem to ask for a refund.
"They said these were still good to eat and that they weren't even in business at that time. I didn't particularly care about eating something that was dated that old."
So, Mae contacted 7 On Your Side and we called NutriSystem.
The company said those numbers on the containers were not dates, they were lot numbers. The company did agree to refund all of Mae's money anyway, because she was dissatisfied.
NutriSystem says none of its products are that old, and in any event, they have a very long shelf life.
So we wondered, how important are those "best if used by dates" you see on your groceries?
"That's an arbitrary date, put on it by the food processors," says food and safety expert Lawrence Pong.
Pong says the dates have more to do with quality and nothing to do with safety.
"They could be over a decade old and it's still good."
He says older food probably won't taste as good, but it won't make you sick either.
"It doesn't mean you will die if you eat this. It doesn't mean you will get sick if you eat this. We have been so conditioned to look at these dates on the packaging and then we are more or less brainwashed into throwing these things out, " says Pong.
Pong says many products contain oils that might turn rancid.
"Just because it's rancid, doesn't mean it's not good to eat. In a famine, I would eat it."
Of course, if cans or bottles are damaged, or if food did not get required refrigeration, then they're probably not safe to eat. But by law, the only foods that must be pulled off the shelves if they're expired are baby formula and milk.