Vitaminas Verdadeiras e as de Imitação?

As vitaminas baratas são estas coisas feitas de petróleo?
Veja como são feitas estas imitações de vitaminas sintéticas, baratas e as verdadeiras. E onde as pode encontrar.
Are we killing ourselves with the cheap Synthetic vitamins developed from the pharmaceutical industry?
Have a look ! 
"Chemical Form of Food and Non-Food Vitamins"
Vitamin A/Betacarotene
(Carrots)
Methanol, benzene, petroleum esters; acetylene; refined oils
Vitamin B-1
(Nutritional yeast, rice bran
Coal tar derivatives, hydrochloric acid; acetonitrole with ammonia
Vitamin B-2