Ester-plex® is metabolised (processed) in the body and is broken down into secondary compounds (metabolites). These natural vitamin C metabolites found in Ester-plex may cause vitamin C to be absorbed into the bloodstream faster than ordinary vitamin C. Ester-plex® contains Threonic acid, a natural metabolite of vitamin C. Threonic acid may be responsible for increased bioavailability. Ester-plex® provides co-factors Acerola, Camu Camu, Citrus Bioflavonoids and Rosehips. Ester-plex® is a buffered form of vitamin C that may reduce the possibility of gastric irritation.