What happens when you chew and swallow?

Treatment for head and neck cancer can change the way you chew and swallow.  This can affect how you eat and drink after your treatment. These side effects can depend on where in the head and neck the cancer started, the stage, and type of treatment.

Chewing prepares food in the mouth to make it easier to swallow. The tongue moves the food around in the mouth. Saliva moistens the food and your teeth break it down until it forms a soft, moist ball (bolus) that is ready to swallow.

Swallowing happens in 3 stages:

• the mouth stage
• the throat stage
• the gullet stage.

Eating difficulties can be caused by problems at 1 or more of these stages.

Mouth stage of swallowing

1. When food is ready to be swallowed, the tip of the tongue squeezes against the roof of the mouth. This moves the food to the back of the throat (pharynx).
2. The soft palate moves up, closing the gap between the nose and mouth. This stops food from passing into the nose.

Throat stage of swallowing

1. As food moves into the throat, the muscles in the base of the tongue and throat (pharynx) squeeze together. This moves food down.
2. Your voice box (larynx) lifts in your throat. A flap of tissue called the epiglottis closes the airway and stops food going into the lungs. The gullet (oesophagus) then opens.

Gullet (oesophageal) stage of swallowing

1. Muscles in the gullet squeeze and relax, pushing food down towards the stomach.