The ability to take in liquids through sucking physiologically follows the innate sucking reflex, which is lost between the ages of six and twelve months.

The newborn has an inherent reflex to look for its mother’s breast immediately after birth . If something touches his cheek, it turns its head there. Then, when the nipple touches the lips or the tip of the tongue , the mouth will close around the nipple and the newborn will begin to suckle. It only makes these searching movements with its mouth when it gets hungry – just before the hunger stimulus becomes too strong and it screams for food with all its might.

Just like the search reflex, the sucking reflex is innate in the newborn. Only by sucking can it effectively ingest, swallow and digest food in time . By the age of six to twelve months, the central nervous system is sufficiently developed that the reflex is replaced by voluntary and voluntary sucking.

If the sucking reflex persists as a reflex and does not disappear, it can be a sign of brain damage – just as brain damage can also persist other innate reflexes that normally disappear (such as in infantile cerebral palsy ).

function & task

The ability to absorb liquids through sucking persists throughout life. This process takes place in alternation and coordination with breathing . When you breathe, the esophagus is closed. If a person takes in food or liquid, the trachea is closed by a reflex through the epiglottis so that food and liquid cannot be inhaled into the lungs . 

The ability to suck is linked to functioning motor functions in the mouth area: lips, tongue, jaw , soft palate , pharynx and larynx muscles should be mentioned here. Sucking and swallowing movements, transport and breathing must be motor coordinated, because the aspiration (swallowing) of liquids and food can lead to pneumonia . The cough reflex protects against aspiration .

Diseases & Ailments

The ability to suck, swallow and digest fluids is vital for human survival even after infancy. Sometimes this function can be disturbed. 

This is the case with neurological diseases or diseases in the ear, nose and throat area. The ability to suck fluids and take in nourishment can also be impaired as a result of the human aging process.

A disturbance in the ability to suck and swallow can be recognized by the following signs, which are often not taken seriously: these are frequent choking, coughing and throat clearing, a hoarse or rough voice. Liquid, food and saliva cannot be retained in the mouth and fall or flow out. Due to a lack of muscle activity and a lack of coordination of control, food remains in the mouth or throat for too long. Eating also takes a lot of time. With the poor motor activity and coordination, few or no sucking or chewing movements are evident.

Weight loss , dehydration and bronchitis are the consequences of insufficient food and fluid intake . A sudden fever of unknown cause and pneumonia can also occur.

In order to improve food intake, care must be taken to adopt an upright posture when sitting . The back may need to be leaned or supported. Bent arms lying on the table also help. Liquids can be sucked up in small sips with a straw or a special drinking cup .

Problems with sucking, chewing and swallowing are usually associated with speech therapy problems – articulation of speech – and problems with breathing and digestion. In order to improve the sucking function, speech therapy exercises or exercises of local oral motor skills are necessary.

Diseases that can lead to impaired sucking and swallowing ability are Parkinson’s disease , injuries and tumors of the swallowing street (tongue, palatine arch, tonsils, pharynx, esophagus) or a stroke . After tumor surgery in this region, the problems may persist if the damage is so severe that the ability to suck cannot be restored.

Various neurodegenerative diseases such as Alzheimer’s , multiple sclerosis or severe craniocerebral trauma can result in impaired sucking and swallowing functions.

In people with infantile cerebral palsy, a gothic jaw with misaligned teeth and orthodontic problems can develop as a result of incorrect muscle tone and inadequate innervation in the mouth and throat area . Sucking, swallowing and speech are also disturbed here.

In people with disabilities, the sucking reflex and later the ability to absorb liquids by sucking can be disturbed. Triggers can be any disability that affects the central nervous system .