2. Illness, surgery, or rapid weight loss
According to Dr. Lauren Eckert-Plock, a board-certified dermatologist in Aiken, South Carolina, when the body is under physical stress, such as when fighting an infection or recovering from surgery, large amounts of Hair loss may occur.
“Basically, the body can’t handle doing too many things at once,” Ploch says. “When a stressful event occurs, your body tells you to stop devoting resources to hair growth and focus on this disease.”
Hair usually starts falling out two to three months after the incident, Ploch said. You may also notice that a few strands of hair fall out when you take a shower or brush your hair.
The condition, called telogen effluvium, often occurs after infection with COVID-19, Ploch said. Hair may also fall out after an episode of influenza or pneumonia, major surgery, or significant weight loss. In fact, many people who lose significant weight after taking newer GLP-1 drugs such as Ozempic and Wegovy experience hair loss.
Fortunately, telogen hair loss is temporary, says Ploch. Once you stop taking the medication, your hair will return to normal in about 6 to 9 months.
3. Mental stress
Emotional distress can also cause hair loss, another form of telogen effluvium, Colavincenzo says. She has seen patients who lose their hair after divorce, loss of a loved one, or layoff. Hair loss is also common among caregivers who are under stress, she says.
“People talk about the three Bs: bereavement, separation and bankruptcy,” she says. “Anyone who has a lot of stress in their life is likely to experience hair loss.”
Colavincenzo said she often refers these patients to mental health professionals for treatment. Fortunately, their hair usually grows back once the stress is reduced or they figure out how to manage their hair.
4. Thyroid imbalance
The thyroid is a butterfly-shaped gland located at the base of the neck that plays a role in many bodily functions, including the development and maintenance of hair follicles.
“The thyroid is in many ways like the driver of our body,” Dr. Ploch says. “Thyroid hormones are important. When these levels are low, hair loss can occur because it mimics conditions similar to severe stress.”
Research shows that both an underactive and overactive thyroid can cause hair loss. Women are more likely to develop thyroid problems than men.
Thyroid problems can affect your weight, sleep, energy levels, and mood. But the signs can be subtle, so hair loss is sometimes the first symptom a woman notices, Colavincenzo says.
A simple blood test can measure thyroid hormones in the blood, and medications can treat an overactive or underactive thyroid. Once you treat the problem, your hair loss should resolve.
5. Vitamin or mineral deficiencies
Some studies show that deficiencies in vitamin D, iron, protein, and other nutrients can cause hair loss.
