By Teresa Dumain
Mucus, saliva, sweat -- the mere mention might make you gag, but these icky substances actually help fight germs, prevent allergies, counteract cavities, and more. Here, a closer look at how these and other body fluids actually keep you healthy.
Your bodily fluids may be sticky, smelly, and downright nasty, but your body needs every single substance it makes -- even the disgusting ones -- to function at its best. “People are always looking for ways to limit their bodily fluids — to stop a runny nose or scrape out every last bit of earwax, for example,” says Wendy Stern, MD, an ear, nose, and throat specialist in Dartmouth, Mass. “But each has a specific and important purpose. Mucus helps protect the lungs, and without earwax, you couldn’t hear.”
No one is saying you have to love the stuff, but maybe understanding why each bodily fluid exists could help you hate it less. Here’s how mucus, ear wax, and other bodily gunk help you stay well.
The gross: Those sometimes-slimy, sometimes-crumbly little blobs of snot you blow out of your nose are clumps of mucus mixed with dirt and other debris. "Mucus is made in the membranes that run from the tip of your nose to the base of your lungs," says Dr. Stern. On a normal day, these nasal lining-cells secrete about four cups of mucus, most of which you swallow without noticing. When you're sick, production ramps up and the mucus, which is normally clear, can thicken and change color. White, yellow, or green mucus is a sign of a viral or bacterial infection.
The good: "Mucus helps keep your airways moist so they work properly, and serves as the first line of defense in your nose, trapping bacteria, dust, pollen, and other airborne particles that don't belong in your lungs," says Stern. Mucus also contains antibodies and enzymes that help kill bacteria and viruses. When an allergen irritates your nose or a virus infects the tissue, the mucus-making membranes make extra mucus in an effort to usher out the uninvited guests. To clear a snot-stuffed nose, many experts recommend nasal irrigation (with a neti pot) as a natural way to loosen and drain excess mucus.
Related story: What To Do About Sinus Congestion And Mucus
The gross: If you want to get medical, the official term is cerumen. And if you want to technical, it's not really "wax," but a mixture of secretions from oil and sweat glands in your ear, hair, and dead skin. Ear wax is formed in the outer part of the ear canal, and slowly migrates to the ear opening, where it dries, flakes, and falls out. What gets the ear wax moving? Chewing, talking, and jaw-moving.
The good: Ear wax protects and moisturizes the ear canal so your ears don't get irritated or itchy. It also traps dust and bacteria to prevent them from entering and damaging the ear. Tests have shown that ear wax has antibacterial and anti-fungal properties, which is important because the dark, warm, and moist environment of the ear canal is perfect for hosting germs. "So leave your ear wax alone," says Stern. "And keep cotton swabs away from your ears." The cotton is abrasive and could scratch the canal, you might go too deep and perforate your ear drum, and you'll likely push more wax in than you remove, she adds, which could lead to an earache or even hearing loss. The safest cleaning method: Wipe the outer lobe with a washcloth only; and if your ears feel stuffed with wax, see your doctor.
Related story: Ear Canal Problems
The gross: The unsightly appearance of this thick, yellowish-white ooze signals infection. When germs invade the skin -- in an out-of-control, inflamed zit, for example -- your immune system kicks in for protection. White blood cells rush the area and collect within the damaged tissue. Composed of fluid, dead and dying white blood cells, bacteria, decomposing tissue and other debris, pus is the byproduct of this process. A small collection of pus in the top layer of skin is called a pustule or pimple; when it accumulates into a deep pocket, it's an abscess.
The good: As gross as pus looks, its presence means your infection fighters are working, says Joyce Davis, MD, a New York City-based dermatologist. "The body is trying to engulf something, but sometimes its needs the help of an anti-inflammatory or anti-bacterial to finish the job." For the occasional pimple, a topical over-the-counter acne treatment that contains benzoyl peroxide or salicylic acid provides just enough support to squash the bacteria. Chronic acne breakouts may need prescription ointments, antibiotics, or other medications. Deep abscesses require a doctor's attention -- treatments include drainage and antibiotics. Never pop a zit, which spreads the pus and can possibly cause more infection and scarring.
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The gross: Eye boogers, crusties, sleepies — there’s no official name for the stuff you pick from the corner of your eye in the morning, which is actually an accumulation of dried-up tears. You have thousands of tiny glands that continually make tears; during the day, blinking spreads the fluid around and sends it down a tear duct that drains into your nose, explains Richard Bensinger, MD, a Seattle ophthalmologist. “But when you’re asleep, the blinking stops, so the fluid collects in the corner of your eye and starts to dry, along with whatever debris might have entered the eye shortly before and during sleep,” he says.
But if your eyes are caked shut, or the discharge is yellow or green or has an odor, that’s a sign of infection and you need to see your eye doctor. If you experience pain or can’t see clearly, get to your doctor immediately, adds Richard Shugarman, MD, an ophthalmologist in West Palm Beach, Fla.
The good: Eye discharge is part of your body’s natural defense system to wash away irritants, as well as the normal shedding of the cells that line the outside of the eyes, says Dr. Bensinger. Normally your eyes tear at a slow and steady rate to maintain lubrication, but when foreign matter invades, some tear glands ramp up their output, which forms discharge.
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The gross: If someone says theirs doesn’t stink, don’t scoff — they’re sort of right. Sweat is composed mostly of water, some salt, and small amounts of other substances; on its own, it’s virtually odorless. What makes sweat smell not-so-fresh is the mix of bacteria on your skin and the type of sweat gland it comes from, says Davis. Eccrine sweat glands release unscented fluid directly onto your skin when body temperature rises. Apocrine glands, on the other hand, are linked to hair follicles and are found in areas with lots of them, like your armpits and groin. When you get anxious or stressed out, apocrine glands secrete sweat that contains some fatty acids and proteins; when it gets pushed onto your skin, bacteria begin breaking down the fatty components — and that process stinks.
The good: “Sweat serves as a cooling mechanism for your body,” says Davis. The body functions best around 98.6 degrees Fahrenheit. When your internal mercury rises, you perspire; as the sweat evaporates off your skin, your body cools down. How much sweat you pump out depends on how many sweat glands you have — some people have 2 million, others up to 4 million.
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The gross: Your colon typically absorbs liquids from the food you eat, leaving your No. 2 in its normal, semi-solid state. But if too much food and drink passes too quickly through the colon, your body doesn’t have a chance to absorb enough liquid — and the result is watery stool. Three loose bowel movements in one day officially means you have diarrhea. Not only is the entire experience unpleasant, it can leave you dehydrated, sometimes dangerously so. Loose stools contain more water and electrolytes than solid waste; when the body loses too much, it can’t function properly.
The good: Think of diarrhea as your body’s way of ejecting undesirables, such as viruses, bacteria, and germs from contaminated food and water, from your intestines. It also alerts you to food sensitivities and intolerances, such as to lactose (a sugar found in dairy). Chronic diarrhea usually signals a functional disorder, such as irritable bowel syndrome or Crohn's disease. If diarrhea lasts more than two days, you have severe stomach or rectal pain, a fever higher than 102 degrees Fahrenheit, or your stool contains blood or pus, see your doctor.
Related story: Help For Chronic Diarrhea
The gross: Your mouth makes a ton of this stuff — about four to eight cups a day, which you swallow a little at a time without noticing. If you feel more drooly than usual, it could be because your salivary glands are making more (prompted by certain medications, pregnancy, or reflux, for example) or because you’re swallowing less (which could be the result of allergies or a sinus infection). At the other extreme, too little saliva can lead to dry mouth. It’s most often a side effect of medication, but can also be caused by aging and a number of health conditions.
The good: “You couldn’t talk or eat without it,” says Stern. Saliva moistens your mouth, facilitates swallowing, and contains enzymes that break down food and start the digestion process. Your teeth also need it to stay healthy; saliva helps keep them clean (by washing away food particles), prevents tooth decay (by reducing bacterial growth), and fights off infections.
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The gross: That blistery bubble of fluid is actually serum, the clear part of blood that contains water and proteins. Friction is the most common cause of water blisters — a result of shoving your feet into ill-fitting shoes or pulling stubborn weeds without wearing gloves. The rubbing causes the top layer of skin to separate from the one below; serum then leaks from damaged blood vessels and pools in the space, forming a blister. Burns and viral infections, like chicken pox, can cause blisters as well.
The good: “Water blisters act as a natural bandage, protecting the injured skin underneath from bacteria and infection,” explains Davis. So fight the urge to pop the bubble. As long as the blister stays intact, the injury beneath will heal on its own. Cover a small blister with a bandage and large one with a gauze pad to prevent further rubbing; change the dressing once a day until the blister deflates. If the bubble is in a bad spot (like the heel of your foot), cut padded moleskin (avaialable at any drugstore) into a doughnut shape, and stick it on with the blister coming through the hole, suggests Davis. This way, you can walk without putting pressure on the blister. If a blister needs to be drained or starts to look infected, see your doctor.
Related story: Home Treatment For Blisters
The gross: Urine may be the least yucky body fluid of the bunch — probably because you’ve seen it tens of thousands of times since the day you stopped wearing diapers. Urine's normal color ranges from a diluted pale yellow (when you’ve drunk a lot of water) to a more concentrated amber (when you’re borderline dehydrated). Though you might shudder a little if your pee looks more orange, or freak out at the sight of blue urine, most changes in urine color are harmless and temporary, usually the result of consuming certain foods or food dyes or taking a prescription drugs. Occasionally, however, weird-looking urine indicates something serious — red-tinged urine could be a sign of a kidney disorder or kidney cancer; dark brown urine may indicate a liver disorder; and cloudy urine could signal a urinary tract infection or kidney stones.
The good: Peeing is one way your body eliminates waste and extra water. After your body extracts the nutrients it needs from food, waste products are left behind in the blood. That’s where the kidneys step in — they filter urea, which is a waste byproduct of foods that contain protein, from your blood and use it to produce urine. Adults eliminate about six cups of urine each day.
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The gross: The emptying of your intestines and stomach through your mouth is just foul, plain and simple. For adults, common causes of vomiting include viral gastrointestinal infections or food poisoning, as well as motion sickness, migraines, pregnancy, serious ulcers, or head injuries. The timing of when you puke could indicate the cause: Shortly after eating points to ulcers; up to eight hours after a meal, food poisoning (although certain bacteria can take longer to trigger symptoms); about six weeks after your last period … hello, baby!
The good: In most cases, vomiting is just another way your body gets rid of things that irritate it, and it often subsides within a day. To feel better while you wait, stay hydrated (with small sips of water or ginger ale), avoid strong odors, and eat bland foods. Sometimes vomiting is a symptom of something more serious. The presence of blood (which can either be bright red or dark brown, like coffee grounds), for example, could indicate ulcers, torn blood vessels, liver failure, or cancer. Call your doctor if you’ve been vomiting longer than 24 hours, have symptoms of dehydration (such as excessive thirst, dry mouth, or dizziness when you stand), there's blood in your vomit, or you start throwing up after a head injury.
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