Hexose transporter that can mediate the transport of glucose and dehydroascorbate across the cell membrane. D-glucose(out) = D-glucose(in) L-dehydroascorbate(out) = L-dehydroascorbate(in) Mainly expressed in testis (PubMed:12504846, PubMed:27460888). Also expressed in small intestine, liver and kidney (PubMed:27460888). GLUT14 is a recent (less than 5 M year old) duplication of GLUT3. Belongs to the major facilitator superfamily. Sugar transporter (TC 2.A.1.1) family. Glucose transporter subfamily.