The Evolutionary Loss of Vitamin C Synthesis in Humans and Other Primates

Why do Humans not produce Vitamin C like other mammals?

Humans do not produce vitamin C like other mammals because of a genetic mutation that occurred in our evolutionary history. Most mammals have an enzyme called L-gulonolactone oxidase, which enables them to synthesize their own vitamin C within their bodies. However, humans, along with some other primates and a few other species, lack the functional gene required to produce this enzyme.

This genetic mutation occurred due to a loss-of-function mutation in the gene encoding L-gulonolactone oxidase, which resulted in the gene becoming non-functional. This mutation is believed to have happened around 40 to 25 million years ago in our common ancestor with other primates. As a result, humans and these other species are unable to synthesize vitamin C internally.

This inability to produce vitamin C has led to a dietary requirement for humans to obtain vitamin C from external sources, such as fruits, vegetables, and supplements. Vitamin C is essential for various biological processes in the body, including collagen synthesis, antioxidant defense, and immune function. Without adequate vitamin C intake, humans can develop a condition called scurvy, characterized by fatigue, joint pain, bleeding gums, and impaired wound healing.

More Answers: