Vitamin C

Unlike nearly all animals, human beings are not capable to manufacture their own Vitamin C from glucose; so, it must be obtained daily through food and supplementation. Animals that can create their own Vitamin C are able to raise production in response to stress, infection, or free radical toxins. Since humans must obtain Vitamin C from outside sources, our diet alone may not give adequate amounts of Vitamin C, particularly in times of stress or illness. The use of tobacco also significantly decreases the absorption of Vitamin C - making it very essential for those who smoke (or who live with those who smoke) to get additional amounts of Vitamin C. Carbon monoxide also destroys Vitamin C - making it very important for those living in the city to boost their intake also.