Why is "Vitamin C and the common cold" trending?

Wikipedia Overview

Vitamin C or ascorbate is a water-soluble vitamin found in citrus and other fruits, berries and vegetables. It is found as a form of ascorbic acid. It is an essential nutrient involved in the repair of tissue, the formation of collagen, and the enzymatic production of certain neurotransmitters. It is required for the functioning of several enzymes and is important for immune system function. It also functions as an antioxidant. Most animals are able to synthesize their own vitamin C. However, higher primates, most bats, guinea pigs, some fish species, and some bird species must acquire it from dietary sources because a gene for a synthesis enzyme has mutations that render it dysfunctional; humans obtain this vitamin from those fruits and vegetables.