Telogen effluvium is a common, temporary type of hair loss that can be triggered by severe stress, illness, or other body changes like childbirth—it pushes as much as 70% of hair into its resting phase, causing hair to fall out. (Paywall may apply.)

Hair loss after childbirth happens because pregnancy hormones paused the normal hair shedding process during pregnancy, so the hair loss is actually your hair cycle 'catching up' with its normal process several months postpartum.

Humans may have as many as 100,000 to 150,000 individual hairs on our scalps, growing at a rate of roughly 1 centimeter per month.

40% of women will have noticeable hair loss by age 50.

Male pattern baldness accounts for more than 95% of hair loss in men and is characterized by thinning hair, hair loss, and a receding hairline.

Male pattern baldness is not solely inherited from the maternal side; its causes are still under investigation, but scientists think the genetic component of this type of hair loss involves multiple genes.

Real-time tracking of individual hair cells has revealed that hairs don't actually get pushed out from the root—instead, hair cells are tugged upward by surrounding tissues that act like tiny motors.

It's been about 30 years since a new hair loss drug was approved in the US, and women currently have no approved pills for hair loss.

Cleopatra purportedly recommended grinding up fly heads and rubbing them on areas experiencing hair loss as a treatment.

In 1909, a top public health official in America wrote in an academic journal that baldness was caused almost exclusively by snug-fitting hats.

Stress contributes to gray hair because when the body experiences stress, the sympathetic nervous system releases specific hormones that influence pigment-producing cells.

So-called 'recession blondes and brunettes' skip hair appointments to save money

One hairstyle trend is seen as a recession indicator: people letting their hair grow darker roots instead of frequently splurging on expensive blonde highlights.

Scalp cooling caps may help prevent hair loss during chemotherapy by temporarily reducing blood flow to the scalp, thereby reducing the amount of chemotherapy that reaches hair follicles.

We're typically born with all the hair follicles we'll ever have, just as women are born with all their eggs.

Women experience heightened bone loss after menopause

Both women and men begin to lose some bone density after age 35, on average, but for the first decade after menopause women lose bone more rapidly due to the significantly decreased levels of estrogen, putting women at heightened risk of osteoporosis and related bone fractures.

Over one million people are estimated to travel to Istanbul each year for hair transplants.

Early menopause, occurring before age 45, can be triggered by certain risk factors

Some potential causes of early menopause include autoimmune disorders, chemotherapy, smoking, and certain surgeries that cause the body to produce lower levels of estrogen and progesterone.

Health problems are being misdiagnosed as perimenopause symptoms

Symptoms of menopause and perimenopause (the premenopause period) can be varied enough that clinicians dismiss them in patients in their mid-30s and onward as just a symptom of hormone level change. In this story, a woman's itching was dismissed as a hormonal change, but after two years and 11 separate doctor consultations, was diagnosed as cancer. (Some users may experience a paywall.)

Humanity's reduced body hair slows down wound healing

Cuts to human skin take twice as long to heal compared to chimps and other mammals. Scientists argue this is due to the reduced number of hair follicles on human bodies. Hair follicles contain stem cells which help repair skin cells faster, so as humanity shed its hair over time, so to speak, it also slowed its wound healing.

A man’s genes can predict his hairline

There’s actually some truth to the idea that you should look at your mother’s father. But genetic research tells us that the full picture is somewhat more complicated. An interesting read on how to use genetics to figure out if you'll go bald (with illustrations).

Perimenopause can last as long as 8 years

Typically lasting around four years, beginning around age 45, some women experience it as early as their 30s. Smoking and thyroid disease are factors that can trigger early perimenopause. Early menopause, which can increase health risks, occurs in about 5% of women. Researchers are still investigating why it occurs.

Menstruation, which occurs monthly, is the release of an unfertilized egg

This routine vaginal bleeding is part of a woman's hormonal cycle and occurs after an egg is released by an ovary during ovulation and isn't fertilized. Also known as periods, this monthly occurrence can cause symptoms including cramping, fatigue, and mood changes.

Rodent research suggests goose bumps may play a role in hair growth—raising questions about if this knowledge could be used to reactive sympathetic nerves in hair follicles to boost hair growth in people.

Treatment-induced menopause is menopause induced by surgery or medicine

Chemotherapy and radiation, as well as oophorectomy (a surgical procedure that removes the ovaries) and a radical hysterectomy can cause a woman to become menopausal. Women that go through medical menopause experience the same symptoms as women that experience menopause caused by natural hormonal cycles.

How menopause affects mental health

Menopause, a natural biological process, occurs in three stages: perimenopause (hormone fluctuations), menopause (end of menstrual cycles), and postmenopause (12 months without menstruation). Hormonal shifts during this time can affect neurotransmitters, increasing the risk of mood disorders.

Menopause and perimenopause symptoms may affect both the mind and body

Women going through these aging transitions may experience some common physical and mental symptoms to varying degrees, including hot flashes, bladder control issues, brain fog, and vaginal dryness. This article dives into some of the most common symptoms women might expect during perimenopause, plus what they can do to relieve them.

Prolonged stress impairs the prefrontal cortex

Burnout isn't just a feeling—it physically affects the brain. Prolonged stress impairs regions of the brain responsible for decision-making, emotional control, memory, and more. It can also lead to chemical imbalances, like reduced dopamine and norepinephrine levels, that worsen these effects.

The anatomy of our hair follicles explains goose bumps

The arrector pili muscle contracts when we're cold or scared, causing hairs to stand up and the skin to form the bumps known as goose bumps. This reaction is typically involuntary.

Long-term goose bumps are something to flag to your doctor

Although rarely a cause for concern, persistent goose bumps with no known cause could be a symptom of something to discuss with your doctor, including anxiety, a hair follicle blockage, or conditions that arise from an overreaction of the autonomic nervous system.

Repeated head injuries can lead to CTE and early dementia

Chronic traumatic encephalopathy is a progressive neurodegenerative disease caused by repeated trauma to the head. The condition has become a particular concern in sports like football and soccer, from youth to professional leagues, where repeated low-level concussive events are likely.

What to know about early and premature menopause

Although it's rare, some women may experience menopause early. Early menopause describes women that are menopausal between the ages of 40 and 45. Women that go through menopause before age 40 experience premature menopause. Early experiences of menopause impact under 6% of women, and doctors can’t point to a specific reason why it happens. Learn about what we do know about the conditions here.

Late-onset menopause lowers osteoporosis risks, but heightens the risks for certain cancers

Defined as when a woman starts to experience perimenopause after age 55, this delayed menopause onset is linked to elevated risk of developing breast, ovarian, and uterine cancers.

Perimenopause, which typically occurs in a woman's mid-40s, precedes menopause

Sometimes referred to as the menopausal transition, this time period often lasts around 4 years as the ovaries' production of the reproductive hormones progesterone and estrogen decline. It may be accompanied by mental and physical symptoms including irregular periods, hot flashes, sleep issues, mood swings, and alterations to a woman's sex drive.

Postmenopause is a stage lasting roughly a third of a woman's life

Postmenopause is the final stage of menopause, occurring once a woman hasn't had any bleeding for a full year. She is then considered postmenopausal for the rest of her life. While some of the intense symptoms she might experience during perimenopausal will decline, her risk for certain conditions and diseases will increase.

A 40-something science journalist was getting more winded during workouts, and experiencing night sweats, forgetfulness and tiredness—she thought it was perimenopause, but these common symptoms turned out to be signs of her blood cancer.

Prolonged Grief Disorder has certain recognizable risk factors

This official diagnosis is characterized by intense, daily symptoms of grief a year after the loss of a loved one among adults and faster—around at least six months—for kids and teens. Factors that put people at increased risk of this disorder include being single, attachment anxiety, violent or unnatural death, low education, low income, and multiple losses, among others.