January 6th, 2011
02:00 PM ET

Why we cry: What's inside tears

Whether you just had a fight with a partner or just watched "Revolutionary Road," crying is a natural expression of sadness. But surprisingly little is known about why humans evolved to cry, and what purpose tears serve.

New insights come from the journal Science this week. Israeli researchers studied the question of why we have tears, and found that tears may actually have chemical signals that - at least in men - lower testosterone and reduce sexual arousal.

Tears shed in emotion are actually chemically different from tears created to keep the eye moist and clean, scientists say. And it's the tears of deep feelings that seem to have the effects on arousal and  testosterone .

"We’re smelling each other a lot more than what we’re aware of," said Noam Sobel of the Department of Neurobiology at the Weizmann Institute of Science in Rehovot, Israel. "We’re constantly collecting information, emitting signals, and these things influence our behavior."

It's not that you can spray tears, or even that you should try to cry more, in order to influence other people in certain ways, Sobel said. And these signals are just one part of communication between humans; they don't "take you over," he said.

Researchers gave the male participants samples of tears that women had shed while watching sad movie scenes on separate occasions, as well as saline solution. They did not see the women cry, and did not know that the compound they were sniffing was made of tears shed in emotion.

The men could not distinguish these two liquids in terms of smell, but the tears were having measurable effects on them that they were probably completely unaware of. One part of the study found that men who sniffed the women's tears reported lower sexual arousal, but not sadness, than when they sniffed the saline. A separate research component did brain imaging of male participants, and corroborated the men's self-reported lower sexual arousal when sniffing tears.

This is not, however, a large study. There were 24 men who attempted to distinguish between tears and saline. Then, 50 men watched a sad movie once after sniffing tears and once after smelling saline. To look at sexual arousal in the brain, 16 men participated. While a good start to look at these questions surrounding tears, the small number of volunteers means more research should be done to confirm these findings. Also, it was done only with female tears and male participants; a different pattern might be seen in females who smell emotional tears.

But the findings might, for example, explain why women tend to cry more during menstruation, a time of the month that - at least from standpoint of reproduction, as well as certain cultures - is inappropriate for sexual activity, he said. And there is evidence from animals that tears also lower aggression in others.

"If you have a way to lower testosterone at a time when lowering testosterone is in your interest, it's obviously an effective tool," Sobel said.

Now that you know more about tears, check out what's inside your spit.

soundoff (147 Responses)
  1. lynn

    haha, and i think the same about men....

    January 6, 2011 at 15:23 | Report abuse | Reply
  2. fatboy


    January 6, 2011 at 15:44 | Report abuse | Reply
  3. notborncynical

    That's interesting and I believe it. If my husband is angry I can make myself cry very easily and he'll back down. Or I can force tears to manipulate a situation with him and get what I want. I do this very rarely, but it does work for me.

    January 6, 2011 at 16:49 | Report abuse | Reply
    • Lola

      Wow. You are a real throwback, darling.

      January 6, 2011 at 20:15 | Report abuse |
    • Johnnyleen

      Your poor husband.

      January 7, 2011 at 10:00 | Report abuse |
    • Frank

      I would love it if someone in society found a visual way to mark this type of woman, a real mark of the beast, in order to serve as a warning for others.

      January 7, 2011 at 10:33 | Report abuse |
    • RW

      I hope you aren't being serious. If so I hope your husband gets a divorce from you SOON.

      January 7, 2011 at 12:07 | Report abuse |
    • ric

      Either you're a good actress or he isn't too bright to be fooled by fake tears.

      January 7, 2011 at 12:31 | Report abuse |
    • agFinder

      Any man thinking this has happened to him dozens of times is deluded. Next time the waterworks come on put cotton in your nose and stand your ground!

      January 7, 2011 at 12:37 | Report abuse |
    • agFinder

      ... sorry, meant to write 'hasn't happened ...' :$

      January 7, 2011 at 12:37 | Report abuse |
    • Ithinkthat

      What a catch! (sarcasm)

      January 7, 2011 at 12:49 | Report abuse |
    • Taylor

      My boyfriend eases up and becomes very supportive when I cry. He's really not his typical fiesty self. He holds and kisses me without expecting anything more. BTW when I cry, its because I'm actually sad / overwhelmed, not trying to make him feel crappy.

      January 7, 2011 at 13:14 | Report abuse |
    • thor

      You really believe yourself. Ask yourself; Have I ever "outsmarted" someone?

      January 7, 2011 at 13:54 | Report abuse |
    • saboth

      Doesn't work in my household. When my wife messes up, and knows its her fault, and starts to cry, she gets the same treatment she was getting before the tears.

      January 7, 2011 at 14:23 | Report abuse |
  4. nick

    "But surprisingly little is known about why humans EVOLVED to cry."

    Lost me at "evolve."

    January 6, 2011 at 17:47 | Report abuse | Reply
    • gettys

      @nick: That's too bad. Never made it past 5th grade science class I suppose?

      January 6, 2011 at 19:23 | Report abuse |
    • slupdawg

      That's OK Nick, I'm sure you're lost all the time.

      January 6, 2011 at 19:24 | Report abuse |
    • John

      I stopped reading at that point myself Nick.

      January 7, 2011 at 10:02 | Report abuse |
    • EvoDevo

      Shame how our science curriculum has failed.

      January 7, 2011 at 12:17 | Report abuse |
    • maddawg

      lmao @ nick.....he got lost at 'evolved'.

      must be another brain-dead, can't think for yourself lemming......

      but just to keep you in the loop...evolution is what helps the life on this planet exist from one time through to another. it is not a new concept and has billions of examples of proof.....everywhere you look!

      did you actually tell your teachers when they taught you these things that you will remain an imbecile and only believe in the cult and idol you know?

      and john,,,,cmon now....you are so lemming, that you entirely stopped reading the moment you saw the word evolve?!?

      ummmmmmmm......no wonder your a blinded, brain-dead lemming......you wont even let YOURSELF learn of anything other than your own beliefs in cults and their idols......i certainly hope you do not procreate....what a shallow, hollow, small-minded world that would be to grow up in!

      i've said it before and i'll say it again...........relgions are for the weak minded, cant think for themselves lemmings.
      (and to blindly follow and totally ignore FACTS in your face that contradict your cult and beliefs....WOW...that must feel pathetic day after day after day after day after day....my bad...i don't need to tell you do i...)

      January 7, 2011 at 13:07 | Report abuse |
    • Fred

      I love how people insist on pegging those who don't believe in human evolution as stupid. It couldn't just be that they have another legitimate belief?

      January 7, 2011 at 13:14 | Report abuse |
    • Fred

      That's so Lemming! Listen to yourself for a moment and then rethink everything you just said. Science is as much a religion as the one all those crazy God people and their idols follow. The truth is that I do feel that most organized religions have been corrupted by the hands of the men who run them, but Climategate is a prime example of science suffering the same failing. the key is to arrive at what is true for YOU. No other person has to feel like you feel and ultimately at the end of the day you have no one else to answer to except yourself and eventually to God for why you felt how you felt and then acted as you did. You can believe in God and Jesus and the creation of man as a sentient being without being "religious" in the most popular sense. I love God, and I firmly believe that the rules of science consistently point to his existence and his creation of our universe. I think if more people on both sides could get their heads around that we'd be a lot more harmonious. Alas, it's not meant to be.

      January 7, 2011 at 13:22 | Report abuse |
    • Skepgnostic

      It's sad really, when metaphysical evidence is right there in from of us but theists with activate their ignorant super-ignore-facts powers. They just want the dividends that they think they will collect in the form of an afterlife buy being credulous.

      January 7, 2011 at 13:23 | Report abuse |
    • Skepgnostic

      @Fred. You are ignoring other religions. You are ignoring other heavens and you are ignoring other hells. Just because you think you have avoided hell in one religion does not mean that you have avoided it in another. Your "Pascual's Wager" faith, like 95% of the religious community, is simply FAIL!

      January 7, 2011 at 13:33 | Report abuse |
    • einstein

      Its much more realistic to believe an invisible man (with a beard) zapped those tears into their eyes.........
      Those who do not believe in evolution should NEVER be given sharp objects to hold.....

      January 7, 2011 at 14:13 | Report abuse |
    • einstein

      Fred- The difference between science and religion is that science can admit when its wrong and strives to collect FACTS..... religion is stubborn and baseless....

      January 7, 2011 at 14:16 | Report abuse |
  5. Inupaaq

    I was HOPING to read something 'definitive' about the Emotional RELEASE – i.e., "Bitter" tears as opposed to "Tears of Happiness or Joy".
    POSSIBLY the CLEANSING of TOXIC or depressive substnaces from the body trhough Tears.

    January 6, 2011 at 19:09 | Report abuse | Reply
  6. Lola

    But what about tears shed in happiness? I cry far for tears when I read or see a happy, moving story than when it's a sad one. I wonder whether the chemical or hormonal makeup is the same.

    January 6, 2011 at 20:17 | Report abuse | Reply
    • Andy

      Are you suggesting that it may have the opposite affect? Like a man would become easily aroused by tears of joy.

      January 7, 2011 at 12:15 | Report abuse |
    • einstein

      I save those tears in a jar and giggle at your joy....

      January 7, 2011 at 14:17 | Report abuse |
  7. Janna

    It's all about hormones and chemicals. That's all we are without our souls... just... chemicals.

    January 7, 2011 at 00:06 | Report abuse | Reply
    • Ruby

      It's the soul that tells the chemicals what to do.

      January 7, 2011 at 11:43 | Report abuse |
    • Phil

      There is no physical evidence supporting that claim.

      January 7, 2011 at 12:18 | Report abuse |
    • Nate C

      Sorry, there's no such thing as a soul. You *ARE* chemical reactions. And when they cease.. "you" no longer exist.

      January 7, 2011 at 13:22 | Report abuse |
    • Ruby

      No physical evidence? Sure there is. Take away the soul and the chemicals no longer function. They break down, separate, and return to the Earth. You recited your creed without thinking boy, what you are really trolling for is an argument about the nature of the soul, but you shall not have it.

      January 7, 2011 at 13:28 | Report abuse |
    • einstein

      Lets all agree now that we have little ghosts inside us.......................

      January 7, 2011 at 14:19 | Report abuse |
  8. ecp67

    Men's arousal decreases when the women is weeping.
    In other news, men's breathing decreases when there is no oxygen present.
    Can't wait for the next scientific breaththrough...

    January 7, 2011 at 01:16 | Report abuse | Reply
    • Zodiac

      Tears work for me... I guess that is why I am who I am....

      January 7, 2011 at 10:04 | Report abuse |
  9. Dimestore novel science

    Oh brother, more junk science. How about spending that reserach money on curing cancer, instead ? You know, something that will actually benefit mankind...Off topic: why do men die first ?
    A; because they want to.

    January 7, 2011 at 07:58 | Report abuse | Reply
    • Heather Jeane

      Yeah, it's just that simple.

      Everyone should stop all research that isn't directly related to the most popular need in the world and focus solely on that in the happy centralized laboratory in perfect land. We will completely ignore the fact that seemingly unrelated scientific discoveries have enormous impacts on other fields. You know for example... stuff NASA put together for that totally unnecessary trip to the moon way back and is now being used to save lives on a daily basis... JUNK ALL OF IT!

      January 7, 2011 at 10:33 | Report abuse |
  10. Heather Jeane

    This would likely go a long ways to explaining why police will more often let off a speeder if she cries.

    January 7, 2011 at 10:22 | Report abuse | Reply
    • T. Brown

      actually i was pulled over and having severe panic attack still recieved ticket. probably bc i didnt flash the pervy cop of Noble ok (ignorant mo fos)

      January 7, 2011 at 20:49 | Report abuse |
  11. Jack Howitzer

    It would also go a long way in explaining why coke'd out losers worry about psychological BS.

    January 7, 2011 at 10:27 | Report abuse | Reply
  12. Valerie

    Who cares what men think.

    January 7, 2011 at 10:41 | Report abuse | Reply
    • Frankly Speaking..

      decent women and sometimes hoes like u..ha!

      January 7, 2011 at 11:40 | Report abuse |
    • Gypsy

      Men think????????????

      January 7, 2011 at 11:52 | Report abuse |
    • Nom Nom

      Well, someones feminine itching is kicking in again...

      January 7, 2011 at 12:01 | Report abuse |
    • Johnnyleen

      Who cares what women think?

      January 7, 2011 at 12:38 | Report abuse |
  13. tom

    This explains why men are turned on by Chuck Norris.

    January 7, 2011 at 11:38 | Report abuse | Reply
    • Erin

      Love it, Tom!

      January 7, 2011 at 12:12 | Report abuse |
  14. Frankly Speaking..

    I hate clowns..i hate fat boys too

    January 7, 2011 at 11:41 | Report abuse | Reply
  15. Ruby

    Let me guess: you posted this cynical remark because are a woman who has had difficult relationships with abusive men, probably starting with your dad?
    Or are you a woman fearing Muslim man?

    January 7, 2011 at 11:50 | Report abuse | Reply
  16. Victoria M

    One little weapon vs the onslaught of male violence against women.

    January 7, 2011 at 11:54 | Report abuse | Reply
  17. Nom Nom

    woman tears equal 0 pu$$y that night

    January 7, 2011 at 11:54 | Report abuse | Reply
  18. Victoria M

    Nice to hear this is a natural defense people (particularly women and children) have to protect themselves in this violent world

    January 7, 2011 at 11:55 | Report abuse | Reply
  19. Catie

    Even worse, a mans tears. Women only like a man who cries for two reasons. When his child is born and when his dog dies.

    January 7, 2011 at 11:59 | Report abuse | Reply
    • Red

      Probably happens if the wife gets pregnant and its unwanted

      January 7, 2011 at 12:12 | Report abuse |
    • Mike

      He can't cry is his mommy or daddy dies? How about if his chld is dying or dead?

      January 7, 2011 at 17:52 | Report abuse |
  20. Catie

    CNN Why did this post get through!!!

    January 7, 2011 at 12:00 | Report abuse | Reply
  21. Suzanne


    January 7, 2011 at 12:04 | Report abuse | Reply
  22. Wax on WAx offfffffffff

    because its funny? /shrug

    January 7, 2011 at 12:05 | Report abuse | Reply
  23. Red

    Its Bill Clinton isnt it?

    January 7, 2011 at 12:06 | Report abuse | Reply
  24. oneStarMan

    I think there must be more than a lowering of Testosterone; there must be a release of Oxytocin or something similar that produces a strong desire in men to embrace women when they cry.

    January 7, 2011 at 12:07 | Report abuse | Reply
  25. Phil

    Who cares? I'm not going to try to get it on with my wife when she's crying. I'm very compassionate and tend to sense these things coming on and offer hugs to comfort the other person.

    January 7, 2011 at 12:14 | Report abuse | Reply
  26. Romny

    You sound quite insecure and are saying what you are to reap the internal satisfaction you receive from doing so. Those who respond, like me, only add to your pleasure – so enjoy!

    January 7, 2011 at 12:17 | Report abuse | Reply
  27. dogs rule

    Yay! Finally! The only thing on the planet that doesn't get the pigs "up"?! woo hoo!

    January 7, 2011 at 12:32 | Report abuse | Reply
    • lucullus

      Your grotesque face is one other thing that doesn't get the pigs up.

      January 7, 2011 at 15:03 | Report abuse |
  28. OICU812

    The whole problem, and reason for your quandary, is in the second sentence of the article. People DIDN'T evolve.

    January 7, 2011 at 12:40 | Report abuse | Reply
    • Tysic

      Just keep asserting that in the face of the ever growing mountain of evidence to the contrary. I hope you enjoy your delusion, but please don't think that you belief in your imaginary friend makes you morally superior to anybody.

      January 7, 2011 at 13:00 | Report abuse |
  29. agFinder

    Definitely true. I know it always turns me off a lot when women start crying while we're having s – e – x

    January 7, 2011 at 12:47 | Report abuse | Reply
  30. Yo yo yo yo

    Yo yo yo dat be right ladies y'all want some you best stop yo cryin

    January 7, 2011 at 12:48 | Report abuse | Reply
  31. Chuck Anziulewicz

    Unless, of course, you are Elaan of Troyius, in which any man who comes in contact with your tears becomes your LOVE SLAVE!

    January 7, 2011 at 12:52 | Report abuse | Reply
  32. mattmchugh

    Yet another reason to ban "Steel Magnolias."

    January 7, 2011 at 13:04 | Report abuse | Reply
  33. palintwit

    I'd like to slam Sarah Palin.

    January 7, 2011 at 13:09 | Report abuse | Reply
  34. Tim

    This just in, women's tears turn men off, but the tears of a noob turn everyone on.

    January 7, 2011 at 13:10 | Report abuse | Reply
  35. Jenna

    @ PimmyZ–I'm guessing you have never been in love with someone who loved you back. Good luck in life.

    January 7, 2011 at 13:12 | Report abuse | Reply
  36. Nate C

    50 people in the study? This is not newsworthy.

    January 7, 2011 at 13:21 | Report abuse | Reply
  37. NDR

    We are emotional beings, and all relationships have emotional ups and downs. I believe we need to support a healthier message to both men and women where emotions are concerned. Of course men aren't turned on while a woman in their life is crying. Why do we consistently attempt to sell this message that men are always 'turned on'? This false belief is supported with an often sold idea that when men aren't 'turned on' it is the womans fault.


    January 7, 2011 at 13:25 | Report abuse | Reply
  38. arthurr

    look- just forget this 'evolved' crap. IT NEVER HAPPENED FOLKS! We never evolved. never. We were created just like this from an awesome being. Tear ducts were DESIGNED. Did the building you are sitting in right now EVOLVE? of course not. Bricks and wood could never come together by themselves to create a house, neither could atoms (created by themselves from a big bang?????) come together to make you. Grow up and seek God while there is still time. Evolution is a lie and fairy. find the real God. he exists and loves you.

    January 7, 2011 at 13:31 | Report abuse | Reply
  39. Shan

    Revolutionary Road was hell to watch. If I cried, it's not because it was sad. Blech.

    January 7, 2011 at 13:35 | Report abuse | Reply
  40. talon10

    What about a woman who cries during orgasm? I knew a girl like that once. I liked to think it was tears of joy but....

    January 7, 2011 at 13:35 | Report abuse | Reply
  41. Ignorant Christians

    @ arthurr, wow, you are extremely ignorant. And your defense is just as ignorant as you are. you can't ignore science.

    Also, god is not real.

    When you die, you go rot in the ground, just like the rest of us.

    January 7, 2011 at 13:40 | Report abuse | Reply
    • Mike

      Your soul will not rot. I know you hope that it will so you won't have to face the GOD you say doesn't exist. You will someday.

      January 7, 2011 at 17:20 | Report abuse |
  42. Ignorant Christians

    @ arthurr, wow, you are extremely ignorant. And your defense is just as ignorant as you are. you can't ignore science.

    Also, god is not real.

    When you die, you go rot in the ground, just like the rest of us.

    Self replicating molecules have evolved into different substances, including humans. And the humans, erected buildings. This is why the least religious countries are the best to live in, SWEET JESUS!

    January 7, 2011 at 13:43 | Report abuse | Reply
  43. PimmyZ

    Ok...thank you!

    January 7, 2011 at 13:44 | Report abuse | Reply
  44. Vik

    @Ignorant Christians,
    So who created those self-replicated molecules? Why do they have to be here in the first place? Why did we have big-bang? And what was there before big bang? What happens to you after you die? So your entire birth and death is just an accident? You think this entire planet and universe is an accident? Grow up and accept that there is something extremely powerful that initiated all these. It also initiated evolution, so that we evolve gradually. I do not know the reason. I'm not knowledgeable enough to know the cause. Respect other's opinion first. That would be start to grow up and act responsibly.


    January 7, 2011 at 13:55 | Report abuse | Reply
  45. One Idea

    I have no idea whether there is a god/after-life, and neither do you. How do you know there IS or ISN'T?
    If there is, he/she/it won't send you to a "hell" for not believing, though.
    Both of you should not be insisting you are definitely right. None of us know anything for sure.

    January 7, 2011 at 13:59 | Report abuse | Reply
  46. freetime1


    "I love how people insist on pegging those who don't believe in human evolution as stupid. It couldn't just be that they have another legitimate belief?"

    Would you say that if they believed the earth was flat too? The evidance is in evilution is real. Not believing it means you ignore all the evidence and to some of us that is about as stupid as it gets.

    January 7, 2011 at 14:09 | Report abuse | Reply
    • Mike

      Evolution is real. Really??? Toothpicks evolved? How about computers, cars, the internet? Try going to Dell and ask for all the components that make up one of their computers and blow them up and see how long it takes for a computer to evolve. Don't make any plans in the meantime, because it'll take a few years. Actually NEVER. Go buy a new car and just let it sit out in your driveway or garage a few years. You know what will happen? Will it evolve into a SUV? Nope; sorry Charlie that won't happen. It'll do the same thing your body is doing and that's not evolving. I know those of you who want to believe that God doesn't exist so you can go on living with the belief that you won't have to answer for the life you are living. We all are accountable for living here to someone so why are you so hardheaded when it comes to being accountable to God?

      January 7, 2011 at 17:38 | Report abuse |
  47. no arthurr

    Yes, the building I'm sitting in DID evolve. The great creater (aka builder) came back and saw that we needed different lights. And it changed, and it was good. The creater came and saw we needed additional room. A room was added and it was good.

    January 7, 2011 at 14:15 | Report abuse | Reply
  48. AllHailFSM

    We DID NOT evolve! We were formed, perfectly human, by the Flying Spaghetti Monster (FSM).

    All hail the Flying Spaghetti Monster, the only REAL lord and master of the universe!

    January 7, 2011 at 14:24 | Report abuse | Reply
    • Infant Sorrow

      ...in his Noodly name, we pray.

      January 7, 2011 at 15:12 | Report abuse |
  49. Infant Sorrow

    "We gotta do something!"

    January 7, 2011 at 15:12 | Report abuse | Reply
  50. Infant Sorrow

    How about a similar study that guys feeding crying chicks a chocolate bar or a Krispy Kreme donut can still get laid?

    January 7, 2011 at 15:16 | Report abuse | Reply
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