The straight scoop on multivitamins

Should you take a multivitamin?

And if you do, will that little pill boost your immune system or help you avoid breast cancer or heart disease, as some products now claim?

David Schardt, senior nutritionist with the Center for Science in the Public Interest, says there's no evidence to support that.

"But there is good reason to take multivitamins," Schardt told me. "They help provide some of the nutrients that Americans don't get enough of, like vitamin D, folic acid and vitamin B-12."

Schardt reminds us that nothing will make up for a lousy diet.

"But they will fill in some of the gaps that even people who try their hardest to eat well sometimes don't get enough of," he said.

A multi is fine, but skip the megadoses.

"You can get too much of any nutrient, so it's best to stick to around the RDA levels," Schardt advised. "That's what your body needs. You don't really benefit from any more than that."

By the way, this nutritional insurance doesn't have to cost a lot. Schardt said you don't need to pay more than 10 cents a day for a high-quality multivitamin.