Did you just yawn while reading this article title? Do you think you yawned because you were tired, or because thinking about yawning prompted you to do it?

Yawning is quite “contagious.” Even just thinking about yawning or reading about yawning can make humans yawn.

According to DiscoveryHealth.com, humans have been yawning since the dawn of Man, but no one really knows why we yawn. Most of the information behind yawning causes are just speculation.

MSNBC.com reported that “[i]t’s widely assumed that yawning occurs because we are tired or bored or because we see someone else doing it, but there isn’t any hard evidence to support these beliefs. The most plausible explanation, and the one that is taught in medical school, is that we yawn because oxygen levels in our lungs are low.”

Here are some fun facts about yawning, brought to you by DiscoveryHealth.com:

- Humans yawn before we’re even born; 11-week-old fetuses have been known to yawn in the womb.
- Yawns start becoming “contagious” when we’re between the first and second years of our lives.
- If one person in a group yawns, more than half of the people in the group will yawn in five minutes (the rest will be tempted to yawn).
- Animals have been known to yawn when they see other animals yawning.
- Men yawn longer than women.
- Yawns last, on average, six seconds.
- On a more serious note, if you that you perform frequent yawning, you may want to see a doctor, for you may have an underlying medical condition, one that could be serious.

According to WrongDiagnosis.com, a publication of Health Grades, Inc., frequent yawning could be caused by:

Excessive fatigue and sleepiness
Decreased amount of sleep (see Sleep symptoms)
Prolonged sleep deprivation
Stress
Sleep apnea
Disturbed sleep patterns
Insufficient oxygen in blood
Boredom
Exposure to other people yawning
Awareness of prior yawning (perpetuates further yawning)
Opioid withdrawal
Migraine
Headache
Pre-syncope ie prior to faint
Epilepsy
Coma
Damage to brainstem
Stroke
Cardiac conditions
Cardiac tamponade

While yawning is not considered necessarily dangerous, it could be a symptom of something more serious. If you find yourself yawning more frequently than normal, check your sleep patterns and see a doctor about any potential deficiencies. By the way, the average person will have yawned 3 times while reading this article.

Author's Bio: 

Marcy Moore owns and runs a website marketing company in Phoenix, Arizona, but is also an avid traveler and writer who enjoys helping others get more out of life. When she's not visiting fun locations with her family in the RV, she enjoys relaxing at home on her adjustable bed, where she reads, writes & watches TV.