We all think we know about vitamins – and we’re told they’re essential – but why do really need them and why can’t we produce them on our own? These are a few questions on the mind of intrepid filmmaker and health-freak Bryce Sage who travels from Washington DC to San Francisco to get to the bottom of the vitamin mystery. 和服家政妇、一路上有你 浙江卫视、剑谍