8 Reasons Women Lose Their Hair

2. Illness, surgery or rapid weight loss

When your body is under physical duress — such as when it is fighting an infection or recovering from surgery — you can end up with a lot of hair shedding, says Lauren Eckert Ploch, M.D., a board-certified dermatologist in Aiken, South Carolina.

“Basically, the body can’t handle doing too many things at once,” Ploch says. “When there is a stressful event, your body says, ‘I’m going to stop devoting resources to hair growth and focus on this illness.’”

Usually, hair starts to fall out two to three months after the event, Ploch says. You may even notice handfuls of hair coming out when you shower or brush your hair.

Called telogen effluvium, the condition happens a lot after people have COVID-19, Ploch says. You can also lose hair after a bout with the flu or pneumonia, a major surgery or a large amount of weight loss. In fact, many people who have lost a lot of weight after taking the new GLP-1 drugs such as Ozempic or Wegovy experience hair loss.

Fortunately, telogen effluvium is temporary, Ploch says. Your hair should go back to normal in about six to nine months if you stop taking the medication.

3. Emotional stress

Psychological distress can also cause hair to fall out, another form of telogen effluvium, Colavincenzo says. She has seen patients shed hair after divorce, the loss of a loved one or a layoff. Hair loss is also common in caregivers because of the stress they are under, she says.

“People talk about the three B’s: bereavement, breakup and bankruptcy,” she says. “Anyone dealing with a big stress in their life can have hair shedding.” 

Colavincenzo says she often refers those patients to a mental health provider for treatment. Fortunately, their hair typically grows back once their stress is relieved or they figure out how to manage it.

4. Thyroid imbalances

Your thyroid is a butterfly-shaped gland at the base of your neck that plays a role in many bodily functions, including the development and maintenance of hair follicles.

“The thyroid is like the driver of our body in many ways,” Ploch says. “Thyroid hormone is important. If it’s low, it will mimic a state similar to severe stress, so you can end up with some hair loss.”

Studies show both an underactive thyroid and an overactive thyroid can contribute to hair loss. Women are more likely than men to develop thyroid problems.

Thyroid problems can affect your weight, sleep, energy level and mood. But because the signs are subtle, hair loss is sometimes the first symptom women notice, Colavincenzo says.

A simple blood test can measure thyroid hormones in your blood, and medication can treat an overactive or underactive thyroid. The hair loss should resolve once you treat the problem.

5. Vitamin or mineral deficiency

Some studies have indicated that a shortage of vitamin D, iron, protein or other nutrients could contribute to hair loss.

“Vitamin or mineral deficiencies deprive the hair of necessary nutrients, weakening the hair structure and potentially interrupting normal hair growth,” Marmon says.

Iron deficiency, in particular, has been linked to hair shedding.

If you notice hair loss, experts recommend as a first step asking your health care provider for a basic blood test to check for nutrient shortages.

It’s not necessary to take a supplement unless a deficiency is identified, Colavincenzo says. In fact, getting too much of certain nutrients such as selenium, Vitamin A and Vitamin E may produce the opposite effect and cause you to lose hair.

6. Harsh hair styling or treatments

Sometimes, the way you treat your hair can damage the hair follicle and cause hair loss.

If you often wear your hair in a tight ponytail, bun or braids, if you get regular chemical treatments, if you often wear a weave, or if you subject your hair to frequent heat styling, you can cause breakage and hair loss that can become permanent if the behavior continues.

“Less is more when it comes to hair care,” Ploch suggests. She recommends choosing ammonia-free hair color if possible, and not wearing tightly pulled styles every day.

7. Alopecia areata, an autoimmune disease

Alopecia areata is a complex autoimmune disease that can cause bald spots.

When you have alopecia areata, your immune system attacks your hair follicles, shaving off the hairs underneath the skin. Hair typically falls out in small, round patches about the size of a quarter. In some cases, the amount of hair lost can be extreme.

There is no cure for alopecia areata, but new medications can help restore hair even when the condition is severe.

8. Scarring alopecia

This is a disease often caused by an autoimmune or inflammatory disorder that destroys your hair follicles and replaces them with scar tissue. It can be especially devastating because once the hair follicles are gone, “you can’t get the hair back,” Ploch says.

One common type of scarring alopecia affects your eyebrows and your front hairline first and then works its way toward the back of your head. Some patients with scarring alopecia also experience itching, pain or bumps in the affected area.

Scarring alopecia is usually diagnosed with a biopsy. Treatment should be immediate and aggressive, Ploch says.