Hormones play a powerful role in health, including the growth and appearance of your hair. For women in particular, life stages like pregnancy, perimenopause, and menopause cause shifts in hormone levels that can lead to a spectrum of noticeable changes, from thicker, fuller strands to increased shedding or thinning, and even hair loss.
“Understanding what’s happening beneath the surface can help you better care for your hair through each phase,” says Karen Kaufman, MD, medical director for MIORA at Life Time and functional medicine physician at Kaufman Health and Hormone Center in Louisville, Colo.
Kaufman shares how hormonal changes affect women’s hair, what to expect during these transitions, and tips for supporting the hormonal aspect of hair health.
Key Hormones for Hair Health
You’ve probably heard that healthy hair starts at the scalp, but hair growth (or lack thereof) and how lustrous or supple it is goes even deeper, Kaufman says. Hair health is complex, and multiple factors can cause changes in the hair, including diet, lifestyle, environment, and, notably, hormone status.
“There are a few hormones that can have a big impact on hair health and its growth process,” Kaufman says. “Every stage of life for a woman is associated with hormonal fluctuations, and it’s important to understand that those hormones don’t operate independently. Factors like stress, gut health, exposure to environmental pollutants and toxins, and more can all impact hormone balance.”
These are a few of the key hormones to pay attention to, specifically for their effects on hair health.
Cortisol
Cortisol (a.k.a. the stress hormone) can directly affect hair loss, according to Kaufman. “Many people have experienced this firsthand, with hair loss occurring after a death in the family, a traumatic event, or a stressful job situation, for example,” she says.
Stressful situations cause higher cortisol levels in the body. “High levels of this hormone can drive hair follicles into the telogen (resting) phase where hair simply stops growing,” says Kaufman. “The remaining hair eventually sheds in large numbers because the hair forms what is known as a ‘club hair,’ which is a follicle with a keratin bulb that loosens its anchor to the scalp. This shedding process can happen two to three months after a stressful event.”
Sex Hormones
Estrogen, progesterone, and testosterone are key sex hormones that can strongly influence hair health in women. “Any imbalance of these three hormones, whether one is deficient or in excess, can affect hair density, growth, and loss,” says Kaufman.
“When levels are higher, estrogen can help maintain growth and hair health by extending the hair growth phase — meaning hair can grow longer and thicker looking with less shedding,” Kaufman explains. “Estrogen also improves blood flow and nutrient delivery, which supports scalp circulation. This helps with oxygen delivery to hair follicles and nutrient supply to hair roots. Conversely, when estrogen levels fall, testosterone may become more dominant, which can lead to thinning hair at the crown or temples.”
Kaufman notes that testosterone is complicated because higher levels can promote body and facial hair growth while also contributing to hair loss on the scalp. “This won’t happen to everyone, but testosterone can convert to a hormone metabolite called DHT that can create thinner strands, shorten the growth cycle, and shrink the scalp follicles, leading to hair thinning,” she says.
“Progesterone also plays an important role in hair health as it can protect hair follicles from shrinking and inhibits an enzyme in the body called 5-alpha reductase, which can also convert to DHT to cause thinning.
“All three of these hormones,” Kaufman notes, “can fluctuate quite a bit during pregnancy, perimenopause, and menopause, which is one notable reason why hair health is impacted during these stages.”
Thyroid Hormones
Imbalanced thyroid hormones can also lead to more hair shedding. “Both an underactive thyroid (hypothyroidism) and overactive thyroid (hyperthyroidism) can be associated with hair changes,” Kaufman explains. “Hypothyroidism is a common cause of dry, brittle hair and hair thinning or diffuse hair loss all over (including sometimes the loss of outer eyebrows.) This happens because low levels of thyroid hormone can cause hair to enter a resting phase. When the hair shifts into this phase, it can cause excessive shedding. Reduced oil production in this phase can also cause dryness and breakage. Many women notice more hair in their hairbrush or shower drain, which can be alarming.”
The opposite thyroid condition, hyperthyroidism, can cause increased hair shedding and hair may feel thinner overall. “This happens with a metabolically overactive thyroid, as it can cause the hair cycle to speed up, and hair can shed prematurely,” adds Kaufman. “Additionally, the follicles don’t stay in the growth phase long enough, which can lead to thinner, shedding hair.”
How do hormones affect the hair during and after pregnancy?
As hormones shift during pregnancy, women may notice a variety of new hair changes — both positive and negative.
“Some women experience thicker, fuller hair during pregnancy while others notice hair thinning or loss,” Kaufman notes. “It’s widely variable. Each of our physiologies is different, and our responses to the hormone and thyroid changes that occur during pregnancy can present differently from one woman to another.”
Nutrition choices, including protein intake and food quality, can also affect hair growth during this time. “High-quality, adequate protein intake benefits hair health as hair follicles thrive on protein,” says Kaufman. “Taking high-quality prenatal vitamins can also contribute to hair health as they contain the essential building blocks of hair, such as vitamin B7 (biotin) and vitamins C, A, D, and E, which all support hair health.”
After giving birth, a woman’s hormones fluctuate significantly — this is often why women experience postpartum hair loss. Kaufman says this often happens because it’s a stressful time for the mind and the body.
“Life with a new baby can bring increased stress along with significant hormone and nutrient shifts,” she says. “Altogether, these changes can contribute to hair loss for some women. While it is easier said than done, focusing on nutrient-dense foods, eating enough protein, and implementing practices to manage stress can help support hair health during this time.”
How do hormones affect the hair during perimenopause?
Perimenopause is the stage in a woman’s life before menopause when the ovaries begin to produce less estrogen and progesterone, the two key hormones that regulate menstruation and fertility. When these hormones fluctuate, menstruation can become irregular, and you may notice other signs of hormonal changes, including hair thinning, increased hair shedding, or changes in hair texture or type. For example, some women may find their hair becomes curlier, while others may notice their hair becoming straighter.
“Hormonal fluctuations during perimenopause can be quite unpredictable and often involve changes in estrogen, progesterone, DHEA, testosterone, thyroid hormones, and cortisol,” Kaufman explains. “These hormones directly influence the hair follicle cycle and can lead to noticeable changes in hair density, texture, and growth phases. As a result, some women may experience rapid shedding, thinning hair, or even the growth of unwanted facial hair.”
During perimenopause, there is a decrease in estrogen. At the same time, there may be higher levels or increased sensitivity to androgens such as DHEA and testosterone. This can contribute to female-pattern hair loss while also promoting coarser, unwanted hair on areas like the face, chest, and back.
Perimenopause can also cause thyroid imbalances, which may disrupt the hair growth cycle and cause hair thinning and increased shedding.
This period of change in a woman’s life can also be stressful, resulting in elevated cortisol levels that can push hair follicles prematurely into the telogen resting phase.
Kaufman advises that healthy lifestyle strategies during perimenopause can make a meaningful difference. “Stress management techniques such as deep breathing can be very effective for reducing stress, along with practices like meditation and restorative yoga.”
Kaufman also emphasizes that adequate sleep is essential. “On average, Americans get about six hours of sleep per night,” she explains. “As stress can be ever present, our approach to managing it needs to be active and intentional. Sleep is our time to restore and repair, and we need seven to nine hours to do that. Proper nutrition is also important, including essential vitamins, minerals, and adequate protein intake from a whole-foods focused, nutrient-dense diet.”
The best care during perimenopause truly involves supporting the whole body. Hair is often a reflection of overall health, and while it can become a major focus, improving it typically requires lifestyle interventions.
“Achieving better hormonal balance through diet, exercise, supplements, and, when appropriate, plant-based or bioidentical hormone therapy can all play a role in supporting the health of your hair,” says Kaufman.
How do hormones affect the hair during menopause?
A woman officially enters the menopause stage when she has gone 12 consecutive months without a menstrual cycle. “Hormonal changes during menopause are similar to those of perimenopause but are even more pronounced since menopause is no longer about hormonal fluctuations but rather deficiency,” Kaufman says. “Replacing essential hormones through hormone replacement therapy is one approach to support healthier hair at this stage.”
Kaufman notes that many of the same principles of perimenopause apply during menopause. Stress management and lifestyle factors like diet, exercise, and sleep continue to be important, along with ensuring optimal thyroid function.
“Thyroid health is often best evaluated with a more comprehensive thyroid panel than what is typically ordered by a primary care doctor or even an endocrinologist,” Kaufman explains. “Essential labs include TSH, free T3, free T4, reverse T3, and thyroid antibodies. Often, only TSH is checked, which does not always provide the full picture.”
Working with a well-informed medical provider who also has specific training in bioidentical hormone therapy can help you navigate the hormonal changes your body experiences during this period.
Advice for Those Experiencing Hair Changes in Pregnancy, Perimenopause, or Menopause
Dealing with hair loss, growth challenges, texture changes, or other shifts can be challenging, as it can affect both your confidence and how you present yourself. Understanding the variety of factors that influence hair health can help you make choices that support hair health — and your health overall — at a deeper level.
As experiences vary greatly among women, it is important to talk with your healthcare provider about your specific concerns and work with them to find solutions tailored to you.
