I agree with Jan B., non-nutritive sucking has a physiologic as well as psychologic effect. My colleagues in the neonatal intensive care unit are big believers in NNS, particularly in premies. NNS is known to stimulate the production of lingual lipase, and other gastric hormones which assist in digestion of milk, and a more rapid development of the GI tract. Place a pacifier in your mouth and see what happens, the mouth produces enzymes and fluid that is subsequently swollowed, hence assisting digestion of ingested food. It actually works great( in between breastfeeding). Tom Hale