Postbiotics are bioactive compounds formed during fermentation which can be used to promote or maintain good health. These metabolites include short-chain fatty acids (SCFAs), microbial cell fractions, functional proteins, extracellular polysaccharides (EPS), cell lysates, teichoic acid, peptidoglycan-derived muropeptides, and pili-type structures. Recent studies have shown that postbiotics are effective against various food pathogens, increase shelf life, maintain general health status and alleviate symptoms in some diseases. Although the mechanism of these properties has not been fully elucidated, the positive effects of postbiotics continue to attract attention. In this study, postbiotics in food as a new functional ingredient and their effects on health are reviewed in line with recent scientific studies.