Do people really do this?

In Sri Lanka, some people who are highly concerned about hygiene have developed the skill of pouring liquid from a container straight into their mouths without their lips touching it. Sometimes people do this even if they are served in a glass, because they fear that the rim of the glass may be unclean. I would not be surprised if this practice has its roots in the odious caste system that said that touching anything touched by supposedly ‘low caste’ people made you unclean.

But I have observed the other extreme many times in films and on TV in the US. Someone opens the refrigerator in a home, takes out a carton or bottle of milk or juice, and then drinks straight from it, putting their lips to the mouth of the container. This is even when the people live in a home they share with family members who presumably use the same container. This strikes me as pretty gross. But I have seen it so many times that I think it must be more common that I would have expected.

Is that the case?


  1. John Morales says

    Sure; I drink from directly from the container sometimes; why make a glass dirty if I’m only having a quick quaff? It’s not like I don’t swap bodily fluids with my wife already, so what’s the prob?

    (Don’t you kiss your family members at all? Same thing)

  2. Mano Singham says

    Maybe it’s a cultural thing.

    In the culture I grew up in, kissing on the lips is only done with an intimate partner, never with children, parents, siblings, or anyone else. With everyone else, it is at most a kiss on the cheek.

  3. says

    Well, probably, to tie it back to your last post, it’s mostly superstition.

    After all, why don’t you do it? Because you think it is unsanitary? But if it were really unsanitary, wouldn’t a lot more people be getting sick because of it? (I often make the same argument about the horror stories on the news about how awful our cutting boards are.) Yet overall, we are incredibly healthy, so that the rare errors (e.g., lettuce recalls) make the news.

    We go through life being exposed to all sorts of minor insanitities (unsanitaries?) and our bodies are perfectly capable of dealing with them, as long as the contamination isn’t too high. And that builds our immunities.

    In the end, I guess I’m really not that sure how concerned we ought to be. (But most of my major illnesses don’t seem to be related to this particular concern.) YMMV.

  4. brucegee1962 says

    My grandmother had a story about how when she was a little girl, there was a public fountain with a cup attached in the town square. She would drink from it occasionally when she was thirsty, but she was always careful to only put her mouth on the side of the cup where the handle was, because she thought others wouldn’t have thought to do this.
    Then one day she saw the town drunk drinking from the cup from the exact same place. That was the end of that!

  5. starskeptic says

    Great way to spread whatever’s going around -- my parents would have read me the riot act if one of us got caught drinking straight from a shared container….

  6. John Morales says


    Great way to spread whatever’s going around […]

    I’d worry more about the fridge’s handle. 🙂

  7. Mano Singham says

    I don’t think the dislike of sharing containers is primarily due to the fear of catching germs but because there does seem to be a primal aversion to spit once it has been exuded, even one’s own.

    For example, people swallow their own spit without thinking twice. But I once read about an experiment that when people were asked to spit into a clean glass and then drink their own spit back, they felt repulsed. There seems to be a negative perception about spit once it leaves the body. I have no idea why.

  8. flex says

    So much to comment on here.

    While growing up, working on various farms in SE Michigan, it was quite common for one of the outdoor spigots to have a tin cup attached to it on a chain which everyone used for a drink. All the other workers at least, I don’t recall the paying customers at the riding stable we worked at using it. No one worried about contamination, and it wasn’t even washed all that regularly. It occasionally got a swipe from a rag. I don’t recall anyone thinking it was odd or a health concern. Some would get quite hot on the sunny days, hot enough to blister your lips if you made a mistake of not letting the water cool it down a bit. Others were inside the barn and would slowly turn brown from crud, but were not considered a plague spot. You often gave it a rinse, but never bothered to scrub, and I never heard of anyone even getting the shits from drinking from one of these cups.

    At the same time, drinking anything out of a container, like a soda, a beer, or from a cooler of iced tea, was done without putting your lips over the spout. All the drinking from containers was done without your lips touching them unless you were the only person drinking from that container. The reason this was forbidden was because of backwash, where some of the liquid entering your mouth would end up back in the container after interacting with your saliva. I don’t know if that is true or not, but is was a cultural custom we all adhered to.

    To this day I don’t drink directly out of a container unless I know I’ll be the last one drinking from it.

    Finally, in response to starskeptic @ 8, you would surprised how often your hands touch your face. Studies have been done, mainly with children, using non-toxic, visibly-light colorless but black-light florescent ink, to test how quickly things on your hands get to your face. It’s amazingly rapid.

  9. Ice Swimmer says

    There’s a saying in Finland: “If you drink straight from a jug, you will get children who have a big mouth.”

    When I was a kid or a teen sharing a (soda) bottle (mostly the last few sips) or a cigarette (as a teen, usually the last centimetre or so before the filter) wasn’t out of the ordinary among friends*. And still as adults, people will drink liquor straight from the same bottle.

    * = There is a specific phrase for asking to get the last part/remainder of something in Finnish.

  10. says

    Mano @10. I wonder if the aversion to spit is related to hookworm.

    The hookworm cycle starts with adults in the intestines, which lay eggs that come out in the feces. The feces are stepped on, where the hatched larvae dig into the feet. From their they travel the circulatory system to the lungs, where they are coughed up into the sputum. Which is swallowed and work their way back to the intestines as adults.

    Swallowing another person’s spit with the larvae it is a (probably low probability) way to get hookworm.

  11. Mano Singham says

    Slightly off-topic, I listened to a talk by the county health commissioner about lead poisoning in children and he said what flex @#11 said, the children don’t get lead in their blood by licking paint on the walls but because they touch things that have dust with lead in it and then it goes to their mouths. This dust does originate in lead in the paint but becomes airborne from painted windows. When the windows are pushed up and down, that friction creates paint dust that spreads all over the house.

  12. Mano Singham says

    ahcuah @#13,

    What you suggest is possible. Many hygiene practices originate as measures to combat diseases and then live on even after the danger has ceased to exist.

  13. says

    I don’t buy the “backwash” story. Observe how your mouth works when you drink and you probably won’t either. Unless a person is gargling or rinsing their mouth, “backwash” ought to be close to zero.

    I am having trouble coming up with a good experiment for measuring “backwash”.

  14. says

    PS -- I sometimes put my mouth on another person’s mouth and our tongues touch! Eeew!

    Actually it’s kinda cool. My dog sometimes tried to kiss me, too, and succeeded once after he had been eating some dead woodchuck. Now that was “backwash”

  15. jrkrideau says

    takes out a carton or bottle of milk or juice, and then drinks straight from it, putting their lips to the mouth of the container

    Ugh. I have a similar background to flex @ 11 and a similar reaction.

    @ 16 Marcus
    I think you are underestimating the dangers of “backwash” which I believe is more commonly called “reflex”. Check with your local health department or bartender.

    Experiment to measure reflux.

    Hand person bottle of distilled water, perhaps with a bit of sterile nutrient solution (Bottle of beer?). Have person drink and return bottle. Apply appropriate tests for microbes or whatever.

  16. Sam N says

    Most of the time the risks from the small amounts of saliva are negligible. However, when someone is sick (or a couple days transitioning into or out of that state), especially with a very transmissible virus like mononucleosis, it could result in an infection.

    I’m not at all germaphobic, but I have gotten mono from my willingness to share utensils, drinks, heck I’d even share toothbrushes, though typically don’t. I don’t drink from the (almond) milk carton, but out of politeness, because I understand most other people have disgust responses. I would estimate the lifetime risk of being careless about that as getting sick for one to two 10 day periods. Some may view that as too high a price to pay to not studiously avoid sharing things that may have touched someone’s saliva). But I think it’s more likely driven by an innate or learned disgust response, rather than examining actual risk. I’m respectful of those feelings. It’s just not at all how I choose to live my life.

    @18, growth of microbes from someone taking a sip is a bad way to examine this. Compare the flora from your own sips, to that of the other persons. Both are going to leave a few bacteria that can be amplified easily with an incubator and medium (which is very different from the environment in either of your mouths and GI tract), and the bacteria swapped are virtually never harmful, although absurd microbiome pieces are out there to frighten you! (I’m fat because I shared a drink with someone else who was fat. Yeah…). A real concern would be viruses.

  17. says

    It’s not like I don’t swap bodily fluids with my wife already, so what’s the prob?

    (Don’t you kiss your family members at all? Same thing)

    Well, no. We all have bacteria in our mouths. They are usually in small amounts and kept under control. If you drink directly out of a milk carton, the bacteria now have a field day with lots of food (and cold isn’t really that effective against bacteria).

    I’m not squeamish about sharing stuff. We usually carry bottles with water and tea when we go for a trip and all the family drinks from them, occasionally even friends. But those are drinks without sugar and the bottles get emptied within a few hours at the most.
    My kids are having great fun stealing our glasses, but they know they#ll be in trouble when they drink straight out of the bottle.

  18. says

    Usually drinking from the carton is a signifier for something in a TV or movie plot. It might be to show the character is a “man’s man,” or uncouth. Or that the character does in fact live alone. I’m sure it’s been used at least once as a sign that the character “isn’t from around here,” and doesn’t know you aren’t supposed to do that.

  19. Sam N says

    @20, Giliell,
    Are you kidding me? Cold has a massive influence on bacterial growth rates. Take a sip of two glasses of milk. Leave 1 at room temp, 15 C +, put the other in a refrigerator at 5 C. Wait two days and examine the results.

  20. starskeptic says

    flex says @11:
    You’ve missed my point -- I’ll take the risk from hands over the mainlining of someone else’s pathogens directly onto mucous membranes….

  21. Jazzlet says

    I wouldn’t drink from a carton right out of the fridge because I hate cold drinks. I wouldn’t do it if the carton had been left out of the fridge because yucky waxy carton texture. Generally I wouldn’t do it because I was brought up not to do that sort of thing, for me eating in the street is pretty transgressive.

    And hell yeah, things grow in fridges even apparently clean ones Slime mould in the drainage system anyone?

  22. Sam N says

    @24, Food certainly can degrade, typically when given well over a week (compared to a day or two at 20 C temp). I find fungi tend to be larger problems than bacteria, though. What you might find surprising, is to purchase a pint of milk, pour half of it into a rinsed out, empty bottle. Take a sip from the bottle. And then check each day for detectable odor of lactic acid fermentation. Odds are you won’t find a difference at 24 hour intervals.

    When you purchase regular milk, it already has lactobacillus in it, and is on a timer, even if you do absolutely nothing.

  23. deepak shetty says

    have developed the skill of pouring liquid from a container straight into their mouths without their lips touching it

    My grandmother and dad used to do this and I always assumed it was to avoid rinsing the glass. In villages especially there is an earthen pot with a mug next to it and due to scarcity of water , drinking this way avoids the need of repeatedly washing glasses.

    I would not be surprised if this practice has its roots in the odious caste system

    I doubt it -- the higher castes would never share a utensil with the lower castes.

  24. Mano Singham says


    But it may be a precautionary measure since they may not be sure who has handled it.

  25. deepak shetty says

    To my knowledge ,(atleast in older times) The upper castes would not drink the water itself , it being tainted by touching the glass that touched a lower caste -- hence the segregation of water wells and restaurants etc.

  26. Curious Digressions says

    Like @21 said, it’s mostly depicted to indicate rudeness or that the character is a feral man-child who needs “a woman’s touch” to civilize him.

    As a kid, the rumor of backwash was persistent and used to avoid sharing bottle of soda.

Leave a Reply

Your email address will not be published. Required fields are marked *