Health experts say there is just not enough evidence to say vitamins and supplements can really reduce your risk of heart disease or cancer. 

It's a 12 billion dollar business, so it's not going away.  Kristi King, a registered dietician at Texas Children's Hospital and Baylor Medical College in Houston, says there are some vitamins and minerals which offer benefits.

“Is it a waste of money?  Not necessarily,” she answers, “because we do know that certain vitamins and minerals, such as calcium and Vitamin D supplementation, are extremely important in bone health and preventing osteoporosis.”

Vitamins and minerals do enter your system more effectively when you eat those fruits and vegetables.

“Eat the recommended amount of fruits and vegetables, eat lean proteins, eat whole grains,” King says, “to make sure we're getting the wide variety of vitamins and minerals that these foods provide us, however, that's not reality.”

The business won’t die.

“It’s definitely big business in the United States, and it’s big business in the world, and it’s going to continue to grow.”