TF and inflammatory bowel disease: Since transferrin is a blood plasma glycoprotein with a high affinity for ferric iron and hence transports iron through the circulating to many tissues (e.g., liver, spleen, and bone marrow) (Ogun & Adeyinka, 2018), a lower transferrin saturation can be observed in IBD, as supported by some studies (Bergamaschi et al., 2013; Krawiec et al., 2017; Mecklenburg et al., 2014).