Beneficial health effects of chitin and chitosan

Chitin and chitosan have been recognised for their beneficial health effects since the 1980s. Over the past few decades, numerous studies and several clinical trials have been performed which demonstrated that these compounds can reduce body weight and cardiovascular disease (CVD), improve wound healing, but can also modulate the immune system and demonstrate antifungal and antibacterial activity. In particular, weight reduction and improvement of cardiovascular status are interesting targets as the prevalence of obesity and CVD are increasing. Both diseases are associated with various pathological disorders, including diabetes and hypertension and put a strain on healthcare costs and capacity. In general, lifestyle‐based interventions such as the oral intake of chitin and/or chitosan are becoming increasingly popular as these are easily integrated into current treatments and improve the self‐assertiveness of patients. Of interest, but beyond the scope of this chapter, is the use of chitin‐glucans as supplements in cosmetics. Several studies have demonstrated that chitin‐glucan reduced wrinkling and skin‐ageing, suggesting an interaction between the chitin‐glucan and cells of the epidermis. Although these effects may not be attributed to chitin alone, this does demonstrate the strong biological potential of chitin on cells of the human body. In this chapter, scientific literature has been reviewed that demonstrated the beneficial health effects of chitin and chitosan from an immunomodulatory point‐of‐view. First, we provide an overview of in vitro studies that offer in‐depth mechanistic insights, followed by describing preclinical animal studies. Finally, we list various human intervention trials that most clearly demonstrate the beneficial health effects of chitin and chitosan. Furthermore, we purposely discriminate between data on chitin and chitosan as they are chemically distinct and therefore possibly demonstrate unique effects on health