However, the specific dehydrogenase that converts D-lactate to pyruvate is far less active than that for L-lactate, and it has been suggested that very young infants may be a vulnerable group for D-lactic acidosis. Previous data have shown that urinary D-/L- lactate excretion were not significantly different between 2 groups of 4 month old infants taking a control formula or a formula containing D-lactate producing probiotics for 4 weeks. However, measures were not collected in babies during the first month after birth.