Do vitamin supplements really work?

As recently seen on CBS news, vitamins take another health hit.

CBS News learned six weeks ago that more than 35,000 patients in the largest prevention trial of its kind were told to stop taking them, CBS News medical correspondent Dr. Jon LaPook reports. Tuesday, it became official.

"Taking Selenium or Vitamin E at the doses that we used in the select trial for an average of five years did not prevent prostate cancer," said Dr. Eric A. Klein of the Cleveland Clinic.

Vitamin E: "We have exhausted the possibilities for its role in chronic disease prevention."
Vitamin C: "No effect for cancer prevention."
Vitamin B: "For the prevention of chronic diseases like heart disease and cancer, the evidence does not point to a benefit of B vitamins."

And what about taking a daily multivitamin? "There is a lack of ... solid evidence taking multivitamins regularly have an impact on disease prevention," Coates said.

There are some useful supplements. For example: folic acid during pregnancy, Vitamin B12 for patients who can't absorb it and calcium when dietary sources aren't enough.

So I guess we need to use our own judgement if we should take them or not depending on how they make us feel. The only proven prevention for disease thus far is a good diet and exercise.