Shedding is a natural process that happens to everyone, but losing hair can be quite scary. And let’s be honest, not everyone who loses hair will end up looking like a movie star (take —have you seen the man’s muscles?). So how much shedding is considered "normal," and when should we start worrying?

The Need-to-Know

Most people have about 100,000 hairs on their heads and lose around 100 to 125 hairs per day (imagine trying to ). , the medical term for normal hair loss, occurs because scalp hair grows in cycles. Each undergoes a growth stage that lasts years, followed by a two-month resting stage where no growth occurs. Then, the hair strand falls out and a new one begins to grow in its place.

For a healthy person, this means between 80 and 90 percent of hair follicles are growing hair at one time, while the rest of the follicles are resting or shedding. Losing more than that? Something could be wrong. When the loss per day, it’s no longer just considered "shedding." It could be a condition called "," when something pushes more hairs into the resting phase, says , M.D., a dermatologist at Santa Monica Dermatology Medical Group. There are plenty of reasons for it, though—and the good news is they’re usually reversible (hooray!).

Ever been stressed enough to pull hair out? Well, there may be some truth to that— can contribute to excessive hair loss. Hair+growth+inhibition+by+psychoemotional+stress:+a+mouse+model+for+neural+mechanisms+in+hair+growth+control.+Peters+EM,+Arck+PC,+Paus+R.+Experimental+dermatology,+2006,+Mar.;15(1):0906-6705. Other reasons include lifestyle upsets and . Antidepressants, anti-acne prescriptions, and some forms of birth control can also temporarily disrupt hair’s growth cycle.

Your Action Plan

First off, try to stay calm—stressing over hair loss can frustratingly lead to more of it (haha! Bodies.) Schmidt reccomends taking "the hair-pull test" to figure out if it's worth heading in to see your derm: Grab about 40 hairs an inch from your scalp with your thumb and forefinger, and tug the hair hard enough to pull up your scalp and slide your fingers all along the shaft to the end. Count the number of hairs that fall out, and if there's more than six in your hand, something could be up. You could also try collecting the hairs you lose in a day, Schmidt says, but you might feel significantly more crazy.

Otherwise, try these DIY tricks to nix the hairfall. Since stress is a major cause of hair loss, it’s important to find time to relax and take a deep breath. To help manage it, try getting a massage (fine, alright, you've forced our hand), taking a nap, or getting some good ol’ exercise—never underestimate the power of endorphins! Some studies show a deficiency in iron may lead to excessive hair loss, particularly in women, so eating a balanced diet and can also help ensure healthy hair. Low+iron+stores:+a+risk+factor+for+excessive+hair+loss+in+non-menopausal+women.+Deloche+C,+Bastien+P,+Chadoutaud+S.+European+journal+of+dermatology+:+EJD,+2007,+Oct.;17(6):1167-1122.

Basically, be good to hair, and it will be good back. Too much shampooing, heat-fueled styling, and chemical products and cause it to break off. And beware of the hairbrush too—excessive use can also result in increased shedding. The+effect+of+brushing+on+hair+loss+in+women.+Kiderman+A,+Gur+I,+Ever-Hadani+P.+The+Journal+of+dermatological+treatment,+2009,+Aug.;20(3):1471-1753.

On the other hand, shampooing hair less frequently can make shedding seem worse because it allows loose hair to build up and then all come out in the shower. Nutritional+factors+and+hair+loss.+Rushton+DH.+Clinical+and+experimental+dermatology,+2002,+Oct.;27(5):0307-6938. Unfortunately, human hairs naturally thin with age (referred to as pattern baldness), and this loss is permanent (womp, womp). One half of all men by the time they’re 30, and for females, pattern baldness can begin after menopause. But have no fear—we’re hearing the is coming back in style these days.

The Takeaway

Environmental factors, such as stress, surgery, medicine, and illnesses, can make it seem like your hair is departing en masse, but usually things will right themselves with time. If you're convinced something is terribly wrong, take the hair-pull test and head into your derm: It's better than living with anxiety that could keep the shedding at full strength.

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