How Swallowing Works

Written by: Nimra Khan / Speech / April 05, 2023 / 8 minutes read

I was very privileged to have completed my speech therapy education in England, which allowed me to also have an amazing experience with the British healthcare system, known as the NHS. In March, they have a Swallowing Awareness Day, which inspired me to provide more information here as well, about how we swallow. This is especially important as dysphagia is a condition which many speech therapists encounter, that involves difficulty with swallowing. It might be surprising, but when you consider that much of the same physiology for swallowing food/water is also involved in speaking, this makes SLPs great professionals to have on the team to address it. As swallowing is very closely related to the mechanism for speaking, you can read about how the voice works HERE. 

How it works

There are numerous muscles and nerves involved in swallowing, and all must be timed well in order for it to be as seamless as we usually experience it to be. To understand how it can go wrong, it’s important to understand how it should work.

Stage 1:

We call a piece of food that has been chewed a ‘bolus’. It is pushed backwards by the tongue. Once it has reached a point at the back of the throat, reflexes take over and we don’t consciously control the next stages. 

Stage 2:

The soft palate lifts up to block the passage to the nose, so that it can go down the throat. The epiglottis closes off the passage to the trachea. The bolus is then pushed into the oesophagus. 

Stage 3:

The muscles in the oesophagus contract and relax (called ‘peristalsis’), which allows the food to be pushed down to the stomach, but also to not return back up. 

What can go wrong

Mouth 

Difficulties in this area usually present as difficulty chewing or drooling of saliva. This might occur when a proper seal cannot be created by the lips. Think of when the front of your mouth is numbed when at the dentist, which usually makes it difficult to know if you are drooling or not, and can make it difficult to create a seal around a straw, too. Dry mouth and a need to over-chew can also point towards dysphagia. Some people feel as though saliva is going down their throat before they’re ready to swallow, which can more easily lead to a choking episode.

Oesophagus 

Difficulties in this area present as mucous gathering in the throat because it is difficult to move into the stomach and generally coughing or choking. These are signs that, of course, the body Is trying to remove food that is trying to enter the airway. There can sometimes be regurgitation too, and liquid coming back up through the nose – this links to the contracting and relaxing motion that the oesophagus typically uses, which can be impaired for someone with dysphagia. 

Changes in voice often accompany this – so it’s good to be more aware of swallowing in case there is a link. You can read about more causes of voice disorders HERE. 

SLPs can provide valuable advice to manage dysphagia in daily life. Part of management can be focused on advisement of diet changes that could reduce reflux or the likelihood of choking.

Causes of dysphagia

Aging 

As we age, as with many of the muscles in our body, there are many muscles and processes of swallowing that become weaker too. This might mean that you are more likely to have a coughing fit if you try to talk while eating, you may not be able to eat as quickly as you used to, or different textures/viscosities are more difficult to swallow as well. This is a natural part of aging, but watching out for these signs can help improve your health by reducing the risk of choking!

Other causes include: 

• Nerve damage due to a concussion (find out more about concussions HERE), stroke 

• Parkinson’s or dementia 

• Multiple sclerosis 

• Cancer

• Reflux 

As an SLP, I have seen the most serious cases of dysphagia most often at hospitals and long-term care homes. In the current virtual workspace, I have most often worked with individuals who have swallowing difficulties due to reflux. Many people have reflux without realizing it, which can lead to voice difficulties as well. 

Treatment by an SLP

Aside from the valuable input dieticians, neurologists, ENTs and doctors can provide in especially serious conditions, SLPs can provide valuable advice to manage dysphagia in daily life. Part of management can be focused on advisement of diet changes that could reduce reflux or the likelihood of choking, and also how to complete swallowing exercises that can partially compensate for this difficulty. 

A surprising complication of having swallowing difficulties is the risk for pneumonia. While working in long-term care homes and hospitals, an important part of helping my clients was to ensure they had appropriate dental care as well. This involved helping clients brush their teeth, as bits of food could enter the throat unknowingly – this is especially dangerous when dysphagia is so severe that the individual is not able to have a strong cough, and so the food slips into the open airway and can cause infections.  

I have always been fascinated by the many steps that are involved in the things our bodies do automatically every day, which are easier to appreciate when something goes wrong. I hope you’ve found this dive into how swallowing works to be interesting, and if it has opened up any concerns about your own swallowing, then it would be good to consult with your doctor. 

WELL SAID also offers online communication courses. ‘Breathing for Communication’ could be a good course to consider for self-development. 

To speak with one of the speech-language pathologists at Well Said: Toronto Speech Therapy, schedule an initial consultation by clicking the link below or calling (647) 795-5277.