When a child is breathing normally, the breathing is silent, rhythmic and effortless. The optimal progression is: air is inhaled through the nose while the lips are closed. The diaphragm pulls air deep into the lungs filling them completely. Then, it releases the air allowing the body to oxygenate. When the body is fully oxygenated, the nervous system can exist in a parasympathetic state, a relaxed state that is required for many bodily functions to occur.

Most parents are not aware of whether their child is breathing through their nose or mouth. The following signs will help you identify if they may be breathing through their mouth.

Anything that impedes breathing through the nose for an extended period of time can lead to mouth breathing. For example, food and environmental allergies or frequent colds will cause a stuffy, runny or plugged nose and compel a child to breathe through their mouth.

Mouth breathing has wide-ranging consequences, from those that are just annoying to those that are life-changing. Minor problems include chronically dry lips, mouth and teeth (which increases the propensity for cavities). More often, however, mouth breathing leads to crooked teeth, an underdeveloped jaw and poor development of the face.

When the mouth is left open to breathe, the muscles in the cheeks become taut. These taut cheek muscles apply an external force to the upper and lower jaw which creates a narrowing affect on the dental arches and the face. Also, the tongue, which is meant to naturally rest at the roof of the mouth, drops down into the floor of the mouth. This can cause the upper arch to become narrower (due to the lack of lateral pressure) and the mid-face will not develop normally because the tongue does not push this part of the face out.

A child may end up with a narrow face or with mid-face deficiencies, the outcome determined by genes and other factors.

Two studies in the American Journal of Orthodontics & Dentofacial Orthopedics by dentist Egil Harvold illustrate this phenomenon quite clearly. In both studies, researchers plugged the noses of young monkeys forcing them to adapt by breathing through their mouths. They found that all the monkeys who were made to breathe through their mouth developed crooked teeth and poor jaw and facial development. Specifically, mouth-breathing led to “a lowering of the chin, a steeper mandibular plane angle, and an increase in the gonial angle.” In other words, the face became long and narrow, the jaw less prominent and the chin and the lower jaw retracted.

Impacts of Less Oxygen

Mouth breathers also generally use the wrong body parts to breathe; they initiate breathing in the upper chest as opposed to the diaphragm. Because the body has to exert a great deal of energy to pull the ribs apart to inhale, breathing is labored. Air only fills the upper portion of the lungs and never completely fulfills the body’s need for oxygen. As a result, a chest-breather will take extra breaths or may develop a yawning habit. This is the body’s way of taking in a large volume of air to make up for the oxygen deficit.

This kind of breathing is often erratic, noisy or inconsistent and keeps the individual in a sympathetic nervous system state. This “fight or flight” state does not support many of the biochemical and organ functions that require a relaxed nervous system: digestion, nutrient distribution, sleep and hormonal patterns, growth, healing, recovery from exposure to environmental stressors and toxicity, mental acuity, mood modulation and many others.

Mouth breathing also greatly affects a child’s mental development. Because children who breathe through their mouths are not fully oxygenated, they often do not rest well at night. When they wake up in the morning, they may be tired and find it difficult to maintain focus and attention.

Structural Changes in the Body

To compensate for developmental deficiencies from an abnormal breathing pattern, the body develops a forward head posture. This in turn places undue and long-term stress on the neck, shoulder and cervical muscles, resulting in a chronically tight neck as well as head and shoulder pain. The lower back also becomes arched in an attempt to counter balance the weight of the head leading to weakness or pain in the lower back. And, the adjustment of the body continues with gradual changes to the hips, knees, ankles and feet as well as internal organs that depend on a normal alignment.