Eggs are one of the commonest foods to which people develop food allergies. Portions of the major egg-white protein ovalbumin appear to be the usual culprits. The immune system of sensitive people interprets these parts of ovalbumin to be a threat, and mounts a massive and self-destructive defense that can take the form of fatal shock. Since a sensitivity to egg white often forms in early life, pediatricians commonly recommend that children not eat egg whites until after the age of one. Egg yolks are far less allergenic and can safely be eaten by nearly all infants.