Nucleotides as optimal candidates for essential nutrients in living organisms: A review

Nucleotides (NTs) are the basic units of nucleic acid macromolecules, which are the basis of life. NTs have many important physiological and biochemical functions in organisms. NTs were thought to be synthesized by the body itself without the need for exogenous supplementation. Recent studies have found that exogenous NTs are indispensable nutrients for specific physiological conditions, including immune challenge, starvation, rapid growth, and aging. Exogenous NTs can enter various tissues and be absorbed and utilized, reducing the body’s need for de novo synthesis or salvage synthesis. With concerted effort on the research on NT nutrition, an increasing number of biological functions of exogenous NTs have been reported, including enhancement of immune function and regulation of intestinal flora. This review addresses the digestion, transportation, metabolites, and bio-function of NTs and the sources of NTs in food. The potential applications, future development, and challenges of NTs obtained from food are also explored.