N-acetyl-D-glucosamine (NAG) residues are major structural components of both giardia cysts and trophozoites. Wheat germ contains a lectin (wheat germ agglutinin – WGA) that specifically binds to NAG residues. Commercial wheat germ preparations contain between 13-53mcg of WGA per gm. In vitro research has demonstrated that pre-exposure of giardia cysts to WGA inhibits excystation by more than 90%. Wheat germ agglutinin appears to inhibit excystation by interfering with proteolysis of the cyst wall glycoproteins. In addition, WGA can inhibit the growth of giardia trophozoites in vitro. Wheat germ agglutinin arrests the trophozoite growth cycle in the G2/M phase, thus preventing Giardia growth, replication, and encystation.
Recommended dose: 2 Tbsp of wheat germ three times daily.