Hormonal imbalances related to androgens, estrogen, cortisol, thyroid hormones, or insulin are often responsible for female hair loss. When these hormones are too low or too high, they can shrink hair follicles and shorten your hair growth cycle. These changes lead to thinning hair and hair loss (alopecia).
Hormones regulate a lot of body functions, including hair growth. Hair grows and falls out in a cycle that includes the growth phase (anagen phase), transition phase (catagen phase), and rest or shedding phase (telogen phase). Hormonal imbalances related to the following hormones can influence the length of these phases and how your hair follicles work:
Dihydrotestosterone (DHT)
DHT is an androgen, a primary male sex hormone, that helps males develop facial hair and a deeper voice. However, females also produce low levels of DHT. In both men and women, testosterone converts into DHT to grow body hair and pubic hair.
When DHT levels are too high, the hair follicles on your head can shrink, the growing phase decreases, and the shedding phase increases. These effects cause hair to start thinning on the top of the scalp and spread out from the part line. Hair loss caused by high DHT levels is called androgenic alopecia, also known as female pattern hair loss.
Estrogen
Estrogen is a primary female sex hormone that mainly helps females develop their reproductive system and breasts. The hormone also increases the active hair growth phase for thicker and longer hair.
Low estrogen levels can cause hair follicles to enter the resting phase more often, causing hair to thin and shed in larger clumps. Estrogen also helps block testosterone from converting into DHT in your hair follicles. So, low estrogen levels may also lead to female pattern hair loss.
Progesterone
Progesterone levels fluctuate to regulate menstruation, prepare your uterus for pregnancy, and support pregnancy. Like estrogen, progesterone helps block the testosterone-to-DHT conversion. As a result, low progesterone levels can indirectly cause hair loss by allowing DHT to build up in your hair follicles.
Cortisol
Cortisol is a stress hormone that helps your body react to stress and enter “fight or flight” mode. High cortisol levels caused by physical or emotional stress can cause temporary hair loss called telogen effluvium.
Telogen effluvium occurs when high cortisol levels cause hair to enter an extended resting phase (telogen phase). This causes hair to thin and fall out months after a highly stressful experience. People with telogen effluvium often notice thinning, breakage, and increased shedding on their pillowcases and hair brushes.
Thyroid Hormones
The thyroid gland in your neck helps produce hormones that regulate heart rate, mood, digestion, and breathing. Thyroid hormones also help hair follicles develop and stay healthy.
If the thyroid isn’t working properly, thyroid hormone levels can increase or decrease. Both high and low levels of thyroid hormones can slow the hair growth cycles, causing thin, brittle hair that can shed and fall out.
Insulin
Insulin tells your body to move glucose (sugar) out of your bloodstream and into cells to create energy. If your body doesn’t produce enough insulin, sugar accumulates in your blood and can damage blood vessels. Having no or little insulin limits oxygen, blood flow, and nutrients to your hair follicles. As a result, hair growth can slow, increasing hair thinning, loss, or shedding.
Insulin imbalances can also lead to elevated DHT levels, contributing to female pattern hair loss.
Hormonal imbalances that lead to female hair loss are often triggered by health issues or situations of high stress. Factors that contribute to hormonal imbalances and hair loss in females include:
- Menopause: When you stop having a menstrual cycle and enter menopause, your body decreases levels of estrogen and progesterone. Low levels of estrogen can cause hair to thin and fall out. Low estrogen and progesterone can also allow more DHT to accumulate and cause female pattern hair loss.
- Stress: Physical or emotional stress caused by childbirth, traumatic life events, poor diet, injury, or illness can increase cortisol levels. This can cause hair shedding in large handfuls about a month after high stress. This hair loss is usually temporary and decreases after 6-8 months.
- Thyroid disease: Hyperthyroidism (overactive thyroid) and hypothyroidism (underactive thyroid) can cause temporary hair loss and hair thinning. Treating these conditions usually helps hair grow back, but some thyroid medications can also contribute to hair loss.
- Polycystic ovary syndrome (PCOS): This condition causes the ovaries to produce high levels of androgens like DHT, causing hair loss on the front of the scalp and temples. Treating PCOS with medication can often help hair regrowth.
- Diabetes: People with diabetes do not produce enough insulin to regulate their blood sugar levels. Low insulin levels can also cause hair to start thinning and fall out.
- Genetics and age: If you have a family history of female pattern baldness, you may be more likely to develop high DHT levels. Aging may also increase your risk of increased DHT and female pattern hair loss.
- Hormonal birth control: Females already at risk of high DHT levels may find that birth control pills containing more androgens lead to female pattern hair loss.
Hormonal imbalances that cause hair loss, especially female pattern hair loss, are not always preventable. However, some steps to help improve your health and maintain a better hormone balance include:
- Manage stress: Keep cortisol levels in check by managing stress with hobbies, meditation, yoga, or time in nature.
- Eat a balanced diet: Nutrient-rich meals help your body operate for optimal hormone production.
- Stay active: Exercise regularly to help regulate hormones, like insulin, and de-stress to avoid high cortisol levels.
- Get enough sleep: Aim for at least 7 hours of sleep every night to help regulate cortisol levels and allow your body to rest for improved hormone production.
Hormonal hair loss after birth and menopause usually improves after six months to two years as hormones rebalance. However, hormonal imbalances caused by diabetes, PCOS, or thyroid conditions typically need medical treatment to manage your hormone levels and hair loss. Some ways you can help manage these conditions and treat hair loss include:
- Minoxidil: Minoxidil is approved by the U.S. Food and Drug Administration (FDA) to treat female pattern hair loss. It does not directly lower DHT levels that cause hair loss, but it does increase blood flow to the hair follicles to help regrowth and prevent more hair loss.
- Spironolactone: People with PCOS-related hair loss are often prescribed spironolactone to help block DHT that causes hair loss.
- Thyroid medications: If you have hypothyroidism or hyperthyroidism, taking thyroid medications can help increase or decrease your thyroid hormone levels. This can help rebalance your hormone levels and help with hair regrowth.
- Hormone replacement therapy (HRT): If you’re experiencing hair loss during menopause, HRT that replaces lost estrogen or progesterone levels may help treat hair loss.
See your healthcare provider if you start losing more hair than usual or notice balding patches. Other signs and symptoms that you may need medical care include:
- Fast or sudden hair loss
- Hair loss or thinning in the hair part
- Hair falling out in an unusual pattern
- Losing hair in your teens or twenties
- Hair loss with pain or itching
- Bald spots on your eyebrows
- Sudden weight gain, muscle weakness, fatigue, and extreme sensitivity to cold temperatures
- Increase in acne, facial hair, or abnormal menstrual cycles
- Infected areas on your scalp
Because different hormonal imbalances can cause female hair loss, it’s important to see your primary care provider or an endocrinologist to identify the root cause. An endocrinologist is a medical doctor specializing in treating hormone-related conditions.
If left untreated, female pattern hair loss caused by high DHT levels can become permanent. Delaying treatment for hormonal imbalances caused by untreated diabetes or thyroid conditions can also cause serious health complications.
Many hormones help regulate the hair growth cycles and hair follicle health. Hormonal imbalances related to DHT, estrogen, cortisol, thyroid hormones, and insulin can cause hair to thin and fall out. These imbalances are often triggered by menopause, childbirth, stress, PCOS, diabetes, and thyroid issues. If you notice significant hair loss, see your provider for help.
