So Consumer Reports tested 21 regular daily multivitamins, as well as one for seniors and chewables for children.
"Not everyone needs to take a multivitamin, particularly if you eat a balanced diet. But it's necessary for pregnant women and people on strict diets," said Consumer Reports' Gayle Williams.
Consumer Reports had an outside lab test for the ingredients claimed, as well as contamination. None contained worrisome levels of heavy metals or excessive doses of any vitamin or mineral.
It also tested to see how well the multivitamins dissolve, which is important so you're able to get all the nutrients.
Two of the most expensive multivitamins had a problem. Some samples from Rite Aid's Whole Source Mature Adult and Vitamin Shoppe's One Daily did not dissolve sufficiently. With the One Daily, samples from two of the three lots tested contained only 73 percent of the vitamin A listed.
"The good news is all the other multivitamins passed Consumer Reports' tests, so you can choose by price," said Williams.
One of the least expensive for all three types was Equate from Wal-Mart. And the Kirkland Signature multivitamins from Costco will save you even more.
If you really want to cut your costs, Consumer Reports says look for multivitamin sales and buy in bulk, since many vitamins don't expire for at least a year. But many doctors will tell you, it's best to get your vitamins from eating a well balanced diet.