Hair shedding is a natural process, 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 Vin Diesel — have you seen the man’s muscles?).

So how much shedding is considered typical, and when should we start worrying?

Most people have about 100,000 hair follicles on their head. Hair grows in cycles. There’s a growth stage that lasts 2 to 8years, followed by a resting stage where nothing happens for up to 5 months.

Then, the hair strand falls out and a new one begins to grow in its place as soon as the growth cycle restarts.

We normally lose around 50 to 100 hairs per day (imagine trying to count each one) from hair follicles at the end of the resting stage. Martínez-Velasco MA, et al. (2017). The hair shedding visual scale: A quick tool to assess hair loss in women. DOI: 10.1007/s13555-017-0171-8 Sometimes hair stops growing where it used to. Alopecia is the generic, medical term for hair loss of any kind.

Between 80 and 90 percent of your hair follicles are growing hair at one time, while the rest are resting or shedding. Losing more than that? Something could be wrong. When the loss exceeds 125 hairs per day, it’s no longer just considered “shedding.”

It could be a condition called telogen effluvium, which is the blanket term for when some factor pushes more hairs into the resting phase, says Adriana Schmidt, 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 your hair out”? Well, there may be some truth to that — physical and emotional stress can contribute to excessive hair loss. Other reasons include lifestyle upsets and changes in diet.Almohanna HM, et al. (2019). The role of vitamins and minerals in hair loss: A review. DOI: 10.1007/s13555-018-0278-6

Many prescription drugs like antidepressants, anti-acne prescriptions, and some forms of birth control can also temporarily disrupt hair’s growth cycle.

Frustrating but true: Stressing over hair loss can lead to more of it! Schmidt recommends taking “the hair-pull test” to figure out if it’s worth heading in to see your derm: Grab about 40 hairs, an inch away from your scalp, with your thumb and forefinger, and tug the hair hard enough to pull up your scalp and slide your fingers along the shaft to the end.

Count the number of hairs that fall out. If there are more than six in your hand, something could be amiss. You could also try collecting the hairs you lose in a day, Schmidt says, but that might feel significantly more tedious.

Otherwise, try these DIY tricks to nix the hair fall. 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, twist my arm), taking a nap, or getting some good ole 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 boosting iron intake can also help ensure healthy hair. Guo E, et al. (2017). Diet and hair loss: effects of nutrient deficiency and supplement use. DOI: https://doi.org/10.5826/dpc.0701a01

Basically, be good to your hair, and it will be good back. Too much shampooing, heat styling, and chemical products can weaken hair and cause it to break off. And beware of the hairbrush too — excessive use can also result in increased shedding.

But shampooing hair less frequently can make shedding seem worsebecause it allows loose hair to build up and then all come out in the shower. (So that’s why!)

Unfortunately, human hairs naturally thin with age (referred to as pattern baldness), and this loss is permanent (womp, womp).

According to the American Hair Loss Association, two-thirds of American men will begin to bald by the time they’re 35, and for females, pattern baldness can begin or increase after menopause.

Environmental factors like 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 maybe visit your dermatologist: It’s better than living with anxiety that could keep the shedding at full throttle.