Researchers at National Institutes of Health (NIH) suggest that melatonin, the enzyme which regulates the body's internal clock, may provide an answer to overcoming jet lag and winter blues.
The researchers revealed that the enzyme had been formed more than 500 million years ago and took up the role of timekeeping when vertebrates separated from their non-vertebrate ancestors.
The enzyme was initially responsible for clearing toxic compounds from the eyes but later on started controlling the body's 24-hour cyclic changes.
The researchers added that studying the enzyme's function before and after the divergence had taken place could provide an answer to jet lag and winter blues. The study has been published in the journal PNAS.