Science has just resolved a centuries-old controversy: the way infants express milk from their mothers’ breast. Despite what was believed until now, the secret is not in the pressure of the mouth on the nipple, but in the vacuum that is created in the child’s mouth during sucking. According to this new evidence published in the scientific journal PNAS , obtaining milk is not only due to a physiological movement, but to periodic variations in atmospheric pressure inside the oral cavity, which causes fluid flow with little effort by the newborn.
A team of scientists from New York University, led by Israeli David Elad, analyzed the biomechanical process of breastfeeding through ultrasound images . For this they used an innovative 3D model of the breasts and the milk ducts, responsible for conducting breast milk to the nipple. Observation of the images revealed that the anterior tongue, located between the areola-nipple complex and the lower lips, remains rigid in the cyclical movement of the jaw, while the posterior section of the tongue undulates in a similar way to waves. peristaltics of the small intestine, which generates changes in the air in the mouth, generating a pressure of 27 millibars. The work thus demonstrates that sucking is a dynamic process in which the periodic movement of the jaw and the undulation of the tongue produce variations in subatmospheric pressure that facilitate the instinctive sucking behavior of the baby.
This finding sheds light on the biological mechanism of breastfeeding , which has proven to be vital in the development of the child, since a diet based on breast milk during the first six months of life has been linked to greater cardiovascular health, a lower risk cancer and a higher IQ.
