I've long believed that a varied diet is the best way to get vitamins and minerals to stay healthy, since unprocessed foods contain a wide variety of the nutrients in their natural form, in conjunction with all the other beneficial ingredients that we don't know to measure for yet; given my biases toward real food, it simply has to be better to get vitamins from food that from pills. Well, I just discovered another reason to use real food (especially grown locally) instead of pills: creating the vitamins that go into supplement pills is hard on the environment. Synthetic vitamins are mostly created from petroleum using lovely ingredients like sulfuric acid, ammonia, and acetylene; a few are fermented using various types of bacteria. With the exception of the fermented bacteria, these processes have all the drawbacks of the petrochemical industry: petroleum as a raw material, and toxic materials and pollution as by-products. There is a reason why many of the producers of the raw vitamins are moving their plants to China, where the environmental controls are laxer.
I think I will stick with leafy greens and focus on eating more whole grains.
Source: Twinkie, Deconstructed, by Steve Ettlinger