Vitamins without doubt are vital to our health. And it remains possible that high dose vitamin supplements will one day be proven to protect against illnesses like heart disease and cancer. But so far, definitive evidence for these claims remains largely elusive. And as we discover more about some vitamins, it is increasingly clear that in large doses they can have unexpected, and sometimes dangerous consequences.
Are vitamins doing us any good? Could they even be dangerous? Every year we spend $300 million on vitamin supplements, but do they actually do us any good? Some believe they offer the promise of preventing or even curing some of the world's biggest killers, such as heart disease and cancer. Others claim that taking large doses of some vitamins may in certain cases be harmful. So what are the facts?