All ZeroTVMI products are concentrated blends of highly purified L-amino acids free of threonine, valine, methionine and isoleucine (TVMI) in most cases. ZeroTVMI products are balanced diets for dietary management of methylmalonic aciduria (MMA) or propionic aciduria (PA) - fortified with vitamins, minerals and trace elements. There are several products for each age group, which differ in properties such as dosage form. They can be very easily substituted for one another or combined with each other throughout the day.