The reflex action of yawning, which tempts us all occasionally, is frequently written off as a sign of fatigue or boredom. It is contagious as well. However, the phenomenon of yawning, which has no known cause, can also indicate concerns about our health and wellbeing. Excessive yawning can be a sign of underlying issues that one might not be aware of.
There have been several studies which have linked frequent yawning to underlying health problems, which are mostly related to sleep deprivation. However, the journal Sleep and Breathing published a report in 2009, where frequent and excessive yawning in two women was found to be due to thermoregulatory dysfunction (when the body fails to regulate its internal temperature). Such cases prove that yawning need not necessarily be a sign of sleep disorder, and can also indicate unknown issues within.
Happiest Health spoke to experts who explain why we yawn and the hidden information behind yawning.
Why do we yawn?
While there have been multiple theories validating the phenomenon of yawning– from a process to take in more oxygen with a wide-open mouth to a cooling down mechanism (thermoregulation of the body) — there is no confirmed cause.
“A popular theory is that the brain needs to take in more oxygen when we are tired or hungry, leading to yawning,” says Dr Siri M Kamath, consultant physician, BGS Gleneagles Global Hospitals, Bengaluru.
“The inhalation or inspiration is prolonged, while the exhalation is short during a yawn. It is a mechanism that regulates our body temperature and maintains pressure in our ears,” says Dr Manoj Pawar, pulmonologist, Apollo Clinic, Pune. He adds that yawning can also be the body’s way of being alert when tired.
“Yawning reduces carbon dioxide levels in the body, thereby making one more alert,” says Dr Pawar, adding that there is more blood circulation in the stomach and less towards the brain after eating food, which is why one might be sleepy after lunch or consuming any meal.
Why is yawning contagious?
Yawning is a contagious phenomenon, which spreads when you see someone yawning.
“While there are multiple theories behind the contagious nature of yawning, there is no proven mechanism as to why this happens,” says Dr Kamath.
Excessive yawning: What does it tell you?
Excessive yawning might indicate excessive daytime sleepiness resulting from morbid obesity, lung conditions and obstructive sleep apnea, says Dr Kamath. “It can be a key symptom of these conditions.”
“Excessive yawning can indicate some brain conditions. It is correlated to cases of impaired thermoregulation of the brain due to tumors,” says Dr Pawar.
A study published in the journal Frontiers in Neuroscience in 2014 mentioned that excessive yawning might be seen in stroke patients because of thermoregulatory dysfunction associated with brain injury. “There are some studies which indicate that yawning regulates temperature of the brain, which is why impaired thermoregulation can lead to excessive yawning,” explains Dr Pawar, adding that this might be the reason why yawning is considered to be a cooling down process of the body.
He further cautions that excessive yawning can just be a result of certain sedative medications one might be taking, rather than an underlying issue. “The sedative effect of sleeping pills tends to last up to 12-24 hours, which is why one might experience excessive yawning during the day,” explains Dr Pawar.
“Excessive yawning is usually normal. It should not be taken as a key symptom of serious underlying health conditions. More studies need to be done to confirm the link between excessive yawning and such underlying conditions,” cautions Dr Kamath.
- While there is no known cause for yawning, it is believed to be a mechanism that alerts an individual whenever he/she feels tired, bored or fatigued.
- Certain medical conditions like sleep deprivation and excessive daytime sleepiness can be the reasons for yawning.
- More studies need to be done to confirm the correlation between excessive yawning and underlying health conditions.