Why We Laugh, Why We Cry: A Trove of Trivia About the Human Body

The average person’s heart will beat more than 110,000 times a day. That’s a lot more than the 15,000 times the average person blinks in a day.

Who counts this kind of thing?

Numbers about the human body abound in “Why Don’t Your Eyelashes Grow? Curious Questions Kids Ask About the Human Body.” (October 2008, Avery, $14.95.)


From the smallest muscle (found in the ear) to whether chicken soup really can cure a cold (it can), Beth Ann Ditkoff, former surgeon at New York-Presbyterian Hospital, Columbia University Medical Center, and her daughters Andrea (12) and Julia (10), compiled a list of questions children (and adults) commonly ask about the body.

Chapters range from “Your Body 101” to “The Weird, the Ugly and the Downright Gross” to “Urban Myth and What If.”

The heart-thumping, eye-blinking miracle that is the human body machine is one thing. But I found myself looking at the entries about why we laugh, why we cry, and why we have nightmares — profound questions for the human race at the existential level.

The Ditkoffs, however, explain that we are not the only animals known to laugh and smile. Non-human primates do so too, as a signal to the group that spreads positive emotions, decreases stress, and contributes to group cohesiveness.

“Human-evoked laughter can be divided into three stages,” Dr. Ditkoff writes. The brain chemical dopamine is used to help process humor while also making us feel good when we laugh.

Crying is an altogether different process and experience, but surprisingly may have a similar outcome.

Apart from explaining the three different types of tears, Ditkoff informs us that women cry differently to men. Women average about five crying episodes per month versus one per month for men. Women usually have the type of tears that overflow and run down their cheeks, whereas men’s eyes usually well up with tears but do not produce enough to roll down their faces.

“We don’t know exactly why human beings cry, but it is thought that negative toxins are released in the tears. When you are finished crying, you feel better because these substances have been eliminated from the body.

“Crying may also stimulate brain chemicals called endorphins, which can naturally improve your mood and decrease pain.”

So there you have it from a doctor: If you can’t laugh, have a good cry. Either one will make you feel better.

Changing Planet

Meet the Author
More than forty years in U.S., UK, and South African media gives David Max Braun global perspective and experience across multiple storytelling platforms. His coverage of science, nature, politics, and technology has been published/broadcast by the BBC, CNN, NPR, AP, UPI, National Geographic, TechWeb, De Telegraaf, Travel World, and Argus South African Newspapers. He has published two books and won several journalism awards. In his 22-year career at National Geographic he was VP and editor in chief of National Geographic Digital Media, and the founding editor of the National Geographic Society blog, hosting a global discussion on issues resonating with the Society's mission and initiatives. He also directed the Society side of the Fulbright-National Geographic Digital Storytelling Fellowship, awarded to Americans seeking the opportunity to spend nine months abroad, engaging local communities and sharing stories from the field with a global audience. A regular expert on National Geographic Expeditions, David also lectures on storytelling for impact. He has 120,000 followers on social media: Facebook  Twitter  LinkedIn