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  • Imagine waking up the morning of prom, or your wedding day, or a big job interview

  • and sure enough, you look in the mirror to find your forehead is covered in zits!

  • It's happened to lots of us.

  • Acne, or acne vulgaris, is the most common skin disease in humans.

  • It affects about 80% of people at some point in their lives.

  • Most people get acne between the ages of 11 and 30, but sometimes older people continue

  • to struggle with it, too.

  • Acne happens when follicles and pores become clogged with dead skin cells and oils.

  • Andit sucks.

  • But by studying how acne forms, doctors have developed ways to prevent and treat it.

  • It all starts with your skin: a complex organ made up of two layers and lots of nerves,

  • blood vessels, and glands.

  • Your skin cells regenerate about once a month, so you constantly have dead skin cells sloughing

  • off, and new skin cells rising to the surface.

  • This whole skin-replacement thing isn't much of a problem, on its own.

  • But lots of these dead skin cells come out through your pores.

  • And pores make things more complicated.

  • Skin pores are essentially just openings for tiny hairs.

  • Hair follicles, the root ends of the hairs, are embedded in your skin and surrounded by

  • clusters of sebaceous glands, special glands that produce sebum.

  • Sebum is that oily, waxy stuff that comes out of your pores.

  • It helps keep your skin waterproof and moisturized: it keeps excess water out of your body, and

  • it keeps water already inside you from getting out through your skin.

  • So, sebum is important.

  • But things can go very wrong if your sebum production gets out of whack.

  • When your body doesn't produce enough sebum, your skin can dry out, making you more susceptible

  • to bacterial or fungal infections.

  • But if your body produces too much sebum, it can build up inside your pores, trap dead

  • skin cells, and cause a blockage.

  • Increased sebum production is one of the major factors involved in the development of acne.

  • Increased keratin production is another one.

  • Keratin is a protein produced by your hair follicles.

  • It gives structure to each strand of hair, as well as the top layer of your skin.

  • But when the hair follicles produce too much keratin, the extra protein binds together

  • dead skin cells, so they can't just shed out of the pore like they normally would.

  • You end up with a blockage that then traps more dead skin cells, plus sebum.

  • Once the pore is officially clogged, it becomes a breeding ground for colonies of bacteria

  • especially Propionibacterium acnes.

  • That's a species of commensal bacteria, which basically means it's friendly.

  • It naturally lives on your skin, and it's not harmfulmost of the time.

  • The commensal bacteria that make up your microbiome probably even help prevent other, more harmful

  • bacteria from colonizing on your skin.

  • So having colonies of Propionibacterium acnes living on you isn't a bad thing.

  • You want them thereas long as they stay on the surface of your skin.

  • When the bacteria find their way deep into skin pores where they don't belong, that's

  • when they can cause an infection.

  • And infections often cause inflammation.

  • When you get an infection, your immune system responds by increasing blood flow to the area

  • and sending extra immune cells and enzymes to fight off the infection.

  • Different combinations of symptoms cause different kinds of acne, with names you've probably

  • heard before:Blackheads, whiteheads, pimples, pustulestechnically, they all mean different

  • things.

  • The scientific term for a clogged pore is a comedo, which actually used to mean a parasitic

  • worm.

  • People started using the term to refer to a clogged pore because the stuff that comes

  • out when you squeeze it looks kind of like a worm.

  • When the main symptom is just that the pore is clogged, without much inflammation, that's

  • either a blackhead or a whitehead.

  • Blackheads are what it's called when the comedo is open.

  • The trapped sebum and dead skin cells become oxidized, which turns the surface of the clogged

  • material into a dark color, kind of like how silver tarnishes.

  • When the comedo closes, skin cells grow over the top of the plug and stop this oxidation

  • from happening, so the whitish color of the sebum shows through.

  • That's called a whitehead.

  • When there's a comedo plus an infection that causes inflammation, that's a different

  • kind of acne: pimples!

  • The typical reddish bumpy kind are more specifically called papules.

  • If the inflammation gets really bad, sometimes the bumps start leaking fluid or bacteria-filled

  • pus.

  • Those kind are categorized as pustules, and they're usually a much brighter red, or

  • sometimes white from the oozing fluid.

  • The most severe kind of acne is generally called cystic acne.

  • That's when the infection takes root in the deepest layers of the skin.

  • Sometimes the infection causes more solid bumps to form, called nodules.

  • And sometimes the infection causes pus-filled bumps, called cysts.

  • So that's how acne happens.

  • But what causes it in the first place?

  • What makes healthy pores become clogged, infected, and sometimes ooze-y?

  • Again, there are a few different factors involved.

  • Genetics seem to be important, for one thing.

  • So if your parents had acne, you're more likely to have it too.

  • Hormones also have a huge influence on acnespecifically, androgen hormones, like

  • testosterone, which influence the development of both the male and female reproductive systems.

  • Which explains why acne is so much more of a problem during puberty.

  • Androgen hormones are linked to sebum production.

  • So during puberty, when the hormones are highly active, there's an increase in sebum production.

  • Increased stress has been thought to increase hormone production, as well.

  • So if you find yourself breaking out the day before a big test, that's probably why.

  • When you're stressed, you produce more hormones, which then increases your sebum production.

  • Since sebum is an oil, a lot of people say that greasy foods will cause acne.

  • Sometimes you'll also hear that dairy makes it worse, or even more specific foods, like

  • chocolate.

  • But the truth is, scientists aren't really sure how or whether diet and acne are connected.

  • There have been lots of studies investigating this, and some do suggest a possible link.

  • But others don't.

  • We need more comprehensive, controlled trials with plenty of subjects before we can come

  • to any real conclusions.

  • Doctors do acknowledge that there's anecdotal evidence, and they say that if changing your

  • diet has helped with your acne, then it makes sense for you to stick with it.

  • There just isn't enough evidence to support the idea that diet has a role in acne in general.

  • But we do know that exposure to other topical oils, like some cosmetics or moisturizers,

  • can cause acne by blocking your pores with extra oils and trapping sebum.

  • It's easy to avoid the problem, thoughjust look for products that say they're non-comedogenic,

  • which means that they shouldn't clog your pores.

  • But the natural oil on your face isn't really a problem.

  • You'll often hear that you should wash your face a lot to help prevent acne, but acne

  • isn't caused by dirt or by the natural oil that's already on the surface of your skin.

  • And washing your face too much can actually irritate your skin, making acne worse.

  • To treat acne, the goal is to reduce the factors that come together to cause breakouts.

  • The one thing you shouldn't do is pop a zit.

  • The big risk is that you'll push the infection out of the hair follicle and into the surrounding

  • skin, instead of out to the surface.

  • Plus, you'll irritate the area, causing more inflammation and making the acne take

  • longer to heal.

  • You might also spread bacteria to non-affected pores.

  • Instead, treatments try to lower sebum production, stop dead cells from clumping together in

  • the pore as much, prevent bacterial growth, and lower inflammation.

  • Treatments can range from mild to aggressive, depending on how severe the symptoms are.

  • For mild acne like blackheads and whiteheads, you can usually use topical over-the-counter

  • medications.

  • One of the most effective is benzoyl peroxide, a chemical compound that's really good at

  • killing bacteria.

  • It decomposes into super reactive forms of oxygen, which bind to and destroy the molecules

  • the bacteria need to survive.

  • Another common treatment is salicylic acid, which doesn't kill the bacteria, but stops

  • them from replicating.

  • It can also break down skin cells and keratin to help unclog the pores

  • Inflammatory acne, like papular pimples or cystic acne, sometimes needs stronger treatment

  • to reduce the inflammation.

  • That usually means prescription meds.

  • ###Antibioticsthe kind that are also used to treat other bacterial infections,

  • from strep throat to urinary tract infectionscan be used to treat acne.

  • They stop bacterial growth and reduce inflammation.

  • Another kind of treatment involves retinoids, which are compounds related to vitamin A.

  • Retinoids work by binding to skin cell receptors to remove dead skin cells and encourage healthy

  • skin cell growth.

  • So retinoids work really well to unclog pores full of dead skin cells.

  • They're anti-inflammatory, too.

  • In severe cystic acne cases, stronger retinoids actually work at the deeper layers of skin

  • to reduce the size of the oil glands so they produce less sebum.

  • And since hormones are a big factor in sebum production, using birth control or corticosteroids

  • can regulate female hormones and reduce the amount of androgen hormones being produced.

  • Fewer androgen receptors at work means less sebum production, which means less acne.

  • Sometimes, severe, cystic acne will leave scarring, but there are ways to reduce it.

  • These procedures don't necessarily treat or prevent the acne itself, but they can reduce

  • the bumps and scars left over from bad breakouts.

  • Dermabrasion uses a gentle sanding tool to wear down layers of the skin that have scarred

  • over from cystic acne, but it only works for people with lighter skin.

  • This procedure has mostly been replaced by laser resurfacing, which uses laser pulses

  • to remove skin layer by layer until the scar has smoothed out.

  • Then there are chemical peels, which use compounds like salicylic acid or retinoic acid to perform

  • what's basically a controlled injury to the top layer of skin, killing the top layer

  • of cells.

  • The dead skin cells peel off, revealing healthy skin cells underneath.

  • Luckily, most people grow out of the acne-ridden years of puberty, though some people will

  • continue to have acne well into their 40s and 50s.

  • But even though a bad breakout might make you self-conscious, it's normal, it's

  • treatable, and it's not life-threatening.

  • So take care of your skin, talk to your doctor about prescription treatments if you want

  • them, and trust that your acne will probably get