Drawing a Connection Between Tears and Health
By Loretta Marmer
William Frey, PhD, has been intrigued by the biological basis of crying ever since the day his mother asked him, "Why do people cry tears?"
The biochemist thought he could simply look up the answer in the nearest medical library. He was wrong. "I was surprised to find there is almost nothing written about it," he said.
While Dr. Frey did manage to dig up a few references in the literature, those were either outdated or of questionable validity. As early as 1872, for example, Charles Darwin suggested that crying does relieve stress, but that tears are purposeless. Less than 100 years later, anthropologist Ashley Montagu proposed that crying tears must be a survival mechanism or it wouldn't have evolved as a human function. According to Montagu's theory, when people cry, bacteria and virus-fighting tears moisten the membranes of the nose and throat to ward off infection.
"That theory didn't seem sufficient to me," said Dr. Frey, research director of the Dry Eye and Tear Research Center, HealthPartners St. Paul-Ramsey Medical Center, St. Paul, and professor of pharmaceutics at the University of Minnesota in Minneapolis. "We know that many infants cry without tears when they are first born. It can take days or even weeks before they cry tears. If crying tears were so important, I think it would start (in the first days of life)."
Besides, studies show adults sob in only one out of 11 crying episodes, Dr. Frey continued. That means that 90 percent of the time people cry, there are only tears streaming down the face. "Tears running down your cheek can't be doing much for your nose and throat," he concluded.
Dr. Frey's research shows that 85 percent of women and 73 percent of men said they feel less sad and less angry after a good cry. Intrigued by this finding, Dr. Frey set out to learn why people generally feel better after weeping and hit upon a new theory about the biochemical nature of human tears.
Contrary to conventional wisdom, his theory suggests that all tears are not the same--that emotional tears are different from those shed due to eye irritation. To prove his point, he studied the tears of people who had watched a sad movie compared to those shed by people exposed to onion vapors.
"Emotional tears had a higher protein concentration than irritation tears," Dr. Frey said. The finding surprised him, given that the volume of emotional tears is generally larger and would seem to dilute the protein levels.
Dr. Frey began to examine how the lacrimal glands produce tears and remove substances from the body. His search turned up an interesting piece of information: Researchers have found that in many species of sea birds, such as the albatross, the lacrimal gland performs a function critical to survival.
"The glands remove the toxic levels of salt that would kill the birds," he said. "And there is evidence from other species that the tear gland may have an excretory function," Dr. Frey said.
Knowing this, Dr. Frey began to ponder the possibility that tears likewise remove "toxins" or other harmful substances from the human body. His search for traces of stress-related hormones in human tear glands and tears was fruitful; in the early 1980s, he discovered that enkephalins (a type of endorphin), adrenocorticotropic hormone, prolactin and the element manganese all are present in human tears.
Dr. Frey was especially interested in the presence of prolactin, a hormone produced by the pituitary gland that helps new mothers produce milk. The presence of prolactin, Dr. Frey thought, might provide clues as to why women seem to cry more frequently and with greater ease than men.
"Women cry an average of 5.3 times per month, and men an average of 1.4 times per month...Yet boys and girls under the age of 12 cry the same amount. Something happens between age 12 and 18," Dr. Frey noted. And while he still is not sure of the exact mechanism, Dr. Frey has proposed that prolactin plays a role in the production and excretion of tears.
While there may be biological explanations for the difference in crying patterns among men and women, Dr. Frey cautions not to discount societal conditioning. "Boys, at age 12 or 13, are taught that it's unmanly to cry, that it's a sign of weakness," Dr. Frey said.
"Boys may try to hide their crying from others and cut themselves off from their emotions. They may even hide feelings from themselves. This has bad consequences later in life, since it's important to know how you feel to maintain close personal relationships," he said. "One way to know how you feel about something is if it makes you cry. If you shut that process down, you don't have access to that self-disclosure."
Dr. Frey admits it's difficult to remain emotionally detached when someone around you is crying. "We know it elicits sympathy and empathy. Men don't feel comfortable around people who are crying because they don't want to feel like crying. They are more likely to walk out or disengage and tune out."
This withholding of emotions is unfortunate, he said, and could possibly account for a propensity to engage in substance abuse.
Also, if it's true that crying relieves stress, then stifling the tears could have serious adverse health implications, such as increased risk of heart attacks.
Given the health risks, Dr. Frey urges men, especially, to rekindle their emotional fires. Many men have contacted Dr. Frey hoping he can help them get back in touch with feelings they have not expressed since their pre-teen years. Some may benefit from therapy to learn to get back in touch with their feelings and to cry again, he said.
Dr. Frey hopes that as more people learn about his work, society will become more accepting of public displays of emotion. Change needs to start with our children, he said, and the first step is to validate our children's sad feelings.
The researcher relates an incident that involved his son nearly 10 years ago. Then six years old, the boy was disappointed that the day's weather precluded a previously promised visit to the zoo. He began to cry. Trying to console the boy, relatives pleaded, "Oh, come on, those are just crocodile tears. Grow up and be a man."
"What are these messages? That his feelings are not legitimate?" Dr. Frey asks. "I think it's important that when you see other people cry, you show empathy and sympathy. Don't tell them to stop crying. Nobody cries forever. This is a natural human process for alleviating stress."
Dr. Frey is pleased to say he's already seeing a shift in the way Americans view political figures who wear their emotions on their sleeves for all to see. Some 30 ago, Maine Sen. Edmund Muskie's presidential dreams were dashed when he openly wept while rebutting an attack on him and his wife. Yet the public, and even the media, took little note when Dole and Clinton grew teary-eyed in public while talking about emotional issues.
"For a long time the public demanded poker-faced politicians," Dr. Frey said. But politicians who could hide their feelings from the Russians could be using the same tactics to hide things from the public, too.
"People began to get fed up with politicians who said one thing and then did something else. It's all about distrust. (Now) people are looking for someone they can relate to, who is not afraid to tell us what he really thinks. That has led the pubic to tolerate the show of emotions," Dr. Frey believes.
In the meantime, researchers in Boston and New Orleans are following up the ideas Dr. Frey presents in his 1995 book Crying: The Mystery of Tears (Harper and Row). Yet, he says, not many scientists are seriously studying the role of emotional tears, but instead are focusing on the physiological role of tears in dry eye and other ophthalmologic problems.
Dr. Frey feels crying warrants further study, as it is a uniquely human function. He encourages everyone--man, woman and child--to take advantage of this singular, human opportunity. "We don't have to follow the stereotypic roles society has forced us into," he said. "We have a right to be human."