What's the first thing that comes to mind when you think about hormones? If you're like most people, it's probably your period or reproduction. But did you know that hormones have a significant impact on your brain?
Sex hormones like estrogen, progesterone, and testosterone are involved with brain development even before birth and play a role in memory, mood, and overall cognitive function throughout your life.
This article explores what we know about hormones and the female brain, how they influence brain health, and what happens when these hormones fall out of balance.
In this article:
What Are the Differences Between Male and Female Brains?
People often joke about the stereotypical differences between a woman and a man's brain, but science suggests there's at least some truth that differences exist.
Starting in utero, before you're born, sex hormones influence brain development, and studies have found1 significant biological differences between the appearance of male and female brains.
By the eighth week after conception, androgen hormone levels are much higher for male fetuses, which scientists think2 shapes early differences between the two sexes, especially with right versus left hemisphere development.
Interestingly, research3 also suggests that females with a male twin get more exposure to these androgens, leading to differences in their brains compared to non-twins.
Studies4 also show that men on average have larger brain volume and more white matter (which facilitates communication between the various parts of your brain) while women have more gray matter (where most of the brain processing is done).
It's very important to note that while average differences between men and women as groups exist, this doesn't mean that every single male brain has higher volume or white matter than every single female brain. We're all individuals, and our biological sex isn't the only factor in our brain development.
White matter decreases with age and with dementia. Studies5 show that women are more likely to be diagnosed with dementia, including Alzheimer's disease, possibly because women live longer and have less white matter to begin with. But it also appears that estrogen has a significant role in protecting a woman's brain against dementia, and the big drop associated with menopause plays a big role in dementia.
I'll go into the brain-protective role of estrogen in more detail below, but it's worth noting that research6 suggests that older men have higher estrogen levels than postmenopausal women because testosterone can be converted into estrogen.
Compared to a woman who has gone through menopause, men don't experience the same rapid drop in hormone as they age. This gives us a glimpse into why exposure to sex hormones is so crucial for a healthy brain.
Can Hormone Imbalances Affect the Brain?
Hormone imbalances can cause all sorts of unwanted symptoms and conditions, from acne to infertility, but alterations in hormone balance can also impact the brain.
Research7 shows that hormones influence cognitive function and emotions. Sex hormones are also neuroprotective, meaning they protect nerve cells against damage associated with neurodegenerative diseases. A significant alteration or a drop in hormones (such as seen during menopause) can cause brain changes that influence mood and cognition.
Can Hormone Imbalance Cause Neurological symptoms?
Hormone imbalances don't cause neurological symptoms (aside from more severe endocrine disorders).
Still, there is a link8 between neurological conditions like Parkinson's disease and exposure to sex hormones over time, where more exposure to estrogen can actually protect against these diseases.
Cortisol, Stress, and Brain Health
Cortisol is a hormone commonly called “the stress hormone” (even though other catecholamine hormones and neurotransmitters, such as adrenaline, are also involved in your stress response).
This hormone is vital for energy metabolism and staying awake during the day — just ask anyone with HPA Dysregulation (commonly referred to as adrenal fatigue) and they'll tell you that having issues with cortisol can majorly affect your daily life and energy levels.
And on the other hand, high chronic stress levels are bad for your brain, and research9 suggests that the resulting high cortisol levels may be a big reason why.
Your brain is filled with glucocorticoid steroid receptors that bind to cortisol, which is likely why high stress levels can:
- Cause brain atrophy and decreased brain weight
- Reduce your resilience to future stressors
- Affect cognition and memory negatively.
Women and men can both be affected in these ways by stress and cortisol, but brain imaging studies10 suggest women may have a longer-lasting stress response and their cortisol levels could remain higher for longer than men's in similar situations.
This is why stress reduction practices like exercise, mindfulness, journaling, and meditation are so important.
If you struggle with waking up in the morning feeling refreshed, afternoon slumps in energy, or just plain stress, Adrenal Support is designed to support healthy adrenals, balanced stress hormones, and optimal energy levels.
Which Female Hormones Affect the Brain?
Now let's talk about which sex hormones affect your brain and the “whys” behind them.
Sex hormone11 fluctuations throughout your life, including puberty, pregnancy, and menopause, impact your brain. These hormones can influence brain structure, cellular health and signaling, and DNA transcription (the “writing” of DNA code into RNA molecules that's necessary for life).
Now we'll dive into the following:
- Estrogen effects on the brain
- Progesterone effects on the brain
- Testosterone effects on the brain
Estrogen Effects on the Brain
Estrogen is a primary sex hormone involved in your sexual and reproductive health. It's what gives you breasts and hips and prepares your body for ovulation. The role of estrogen on the brain is fascinating, primarily for its role in memory and protection against neurodegenerative diseases and cognitive decline.
How Does Estrogen Affect the Brain?
Your brain is full of estrogen receptors that act like docks for this hormone to land. When estrogen attaches to receptors, it starts a cascade of cellular changes that impact cognitive functions. Estrogen plays a primary role in brain regions responsible for memory12.
Estrogen impacts how you learn and remember13 via influences on genes and the hippocampus (the brain area responsible for learning and memory).
Multiple studies14 also point toward estrogen's role on brain health later in life, suggesting that prolonged exposure to estrogen starting in puberty improves cognitive status with age.
There are three types of estrogen, each associated with different phases of life, but estradiol which dominates the years while you are menstruating is most important for the brain. One study15 found that women who had their periods for longer were less likely to experience severe multiple sclerosis (a disease impacting the brain and spinal cord).
Another study16 showed that as estrogen levels increase before ovulation, the hippocampus also grows (it also has a lot of estrogen receptors). But as noted above, once estrogen levels drop dramatically with menopause, the risk of degenerative brain conditions17 increases.
Estrogen Hormone Replacement Therapy
So why aren't we giving all women extra estrogen after menopause? Hormone replacement versions of estrogen are mixed with regard to neuroprotection. Some studies have found that it could support brain health if timed right, but it appears that exposure to naturally18 occurring estrogen, primarily estradiol, the best form of brain protection. Still, many experts advocate for some estrogen therapy in order to minimize brain related risks. While the brain is indeed important, we also need to keep in mind that estrogen is also linked to certain cancers, like breast cancer. So a risk versus benefit assessment has to be done for the individual.
Can Lack of Estrogen Cause Brain Fog?
The drop in estrogen is the primary culprit behind brain fog and forgetfulness during menopause. A study19 on women in midlife found that those with lower estradiol levels performed worse on memory tests and had different brain activity, especially in the hippocampus.
While you can't always influence hormone levels after menopause, there are ways to help with brain fog. One study20 found that physical activity improves cognitive function after 50.
Brain fog can also be a sign of low thyroid hormone, so it shouldn’t be ignored or just dismissed as an age issue.
Does Estrogen Affect the Male Brain Too?
Estrogen plays a role in the development of the male brain too and could be protective later in life (though more research is needed). As I mentioned earlier, elderly men21 may have more estrogen than postmenopausal females, which may protect them against higher rates of dementia. One study22 also found that giving men estrogen later in life improved memory for both men and women.
Progesterone Effects on the Brain
Like estrogen, progesterone protects nerve cells and supports healthy blood flow to the brain. Progesterone is a sex hormone that plays a crucial role in pregnancy and regulating your cycle, but interestingly, it's also made by your brain cells23.
How Does Low Progesterone Affect the Brain?
Within the brain, there are receptors for progesterone24, which influences mood and cognitive function. It's also neuroprotective and used to treat traumatic brain injuries (TBI) and strokes25 as it can regenerate and recover cells in the brain and nervous system.
Progesterone supports mitochondrial function26 in brain cells (estrogen can do this too). Mitochondria are tiny structures that regulate all the energy production in the cell, and some research27 suggests that mitochondrial dysfunction or impairment is linked to age-related diseases.
Progesterone could also support improvements in cognitive function, mood, and stress response. It also has anti-inflammatory activity28, which could protect against cognitive disorders.
Does Progesterone Help Memory?
Some research points toward progesterone's role in memory, but the results29 are mixed with studies pointing towards benefits that are dependent on the time of administration.
Progestins, which are synthetic versions of progesterone found in birth control, do not appear to have the same benefits as naturally produced progesterone from the ovaries. One study30 found that women given estrogen and progestin actually had a higher risk of dementia than estrogen-only or placebo. These results point towards issues with progestins, but more research is needed.
Does Progesterone Affect Mood?
Alteration in progesterone can affect mood and concentration because of a metabolite called allopregnanolone. Allopregnanolone31 binds to receptors for the calming neurotransmitter GABA, promoting a sense of calm and relaxation. But when progesterone drops too low, GABA levels can also decrease, increasing feelings of anxiety32 and insomnia.
On the other hand, too much progesterone, which is rare outside of hormone replacement therapy, is associated with depression.
Testosterone Effects on the Brain
Progestins, not progesterone, primarily when taken as a hormonal contraceptive33 is linked with depression.
Testosterone is typically considered a male hormone, but it's essential for everyone. It helps support sexual desire, bone density and affects both male and female brains. Low levels are linked to a risk of Alzheimer's and other degenerative diseases, primarily in men34. Older women with low testosterone35 don't appear to have the same decreases in cognitive performance as men, but more studies are needed as testosterone is understudied in women.
Testosterone could support brain health, but studies36 on the influence of testosterone on the brain are mixed. One study37 found that giving testosterone with estrogen to postmenopausal made their verbal memory worse. But giving testosterone without estrogen may improve verbal memory, according to some research38, so more research is needed.
Can Testosterone Cause Brain Damage?
According to a Yale study39, taking high levels of supplemental testosterone could adversely impact the brain by increasing cell death, but not naturally occurring testosterone.
Is Testosterone Good for Mental Health?
Interestingly, both high and low testosterone40 increases the risk of depression in women. Entering menopause41 with higher than average testosterone levels also increases the risk of depression, so hormone balance is key for mental health.
My FREE Hormone Starter Kit with a 7 Day Meal Plan and Recipes is designed to support optimal hormone health.
How to Support Brain Health
Exercise
Regular physical activity increases oxygen and supports the body in delivering nutrients to the brain. Strength training, walking, and aerobic exercise as part of your daily routine can support brain health.
Brain Games
Sudoku, Lumosity app, crosswords, and other brain stimulating activities can help you train your brain and keep it sharp.
Eat Cold Water Fish
Omega-3 fatty acids are found in cold water fish and have been shown to be highly effective in various neurological conditions. It readily crosses the blood-brain barrier and has shown promise in the treatment of Alzheimer’s disease42, although more research is needed.
Omega-3’s are also anti-inflammatory, which offers the brain protection since inflammation can be a major issue for brain health.
If you struggle with eating fish two to three times a week, you may want to consider a supplement. When using an omega-3 supplement, make sure it is filtered to remove heavy metals and comes from a reputable source.
Keep Your Blood Sugar in Check
Blood sugar regulation is essential for hormone and brain health. Imbalances in blood sugar can lead to a whole host of hormone issues, including elevated testosterone and cortisol, and low progesterone. You can use this free meal plan to build blood sugar balancing meals, while also providing your body the key nutrients it needs to build hormones and maintain brain health.
Hormones and Your Brain: Key Takeaways
- The male and female brains differ, and these changes start before birth partly due to differences in sex hormones.
- Estrogen, progesterone, and testosterone play important roles in brain health, including mood, memory, and overall cognitive function.
- Estrogen especially appears to have neuroprotective effects on the brain.
- Keeping your hormones balanced naturally throughout your lifetime appears most beneficial for brain health.
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