The direct health benefits of diaphragmatic vs non-diaphragmatic breathing has not been extensively researched, but there are changes happening in the body and brain when breathing is not as easy. Default breathing is usually diaphragmatic, but for certain pathologies where the diaphragm is compromised, other muscles have to be used.
Although no direct health benefits have been proven, people are often told that diaphragmatic breathing is healthier than non-diaphragmatic breathing. Despite this, our bodies are designed to breathe with the diaphragm by default and only turn to other muscles in cases of compromise.
Lung surfactant is a fluid line that makes it easier to stretch newborn babies' lungs during development, and is produced sometime between the late second and early third trimester. Without it, it is much more challenging to take care of them.