Women are more likely to develop dementia than men, and scientists think a hormone called estrogen might be part of the reason. Researchers reviewed dozens of studies to understand how estrogen levels throughout a woman’s life—from puberty through menopause—might connect to brain health problems. They found that estrogen appears linked to several health issues that increase dementia risk, including high cholesterol, smoking, and depression. While the connection isn’t completely clear yet, this research suggests that managing estrogen levels at important life stages could potentially help protect women’s brains as they age.

The Quick Take

  • What they studied: How the hormone estrogen throughout a woman’s lifetime might be connected to brain health and dementia risk
  • Who participated: This was a review of existing research, not a new study with participants. Scientists looked at many previous studies about estrogen and brain health in women
  • Key finding: Estrogen appears to be connected to some health problems that increase dementia risk, especially high cholesterol, smoking habits, and depression. However, scientists need more research to fully understand these connections
  • What it means for you: This research suggests that paying attention to estrogen-related health factors—like managing cholesterol, avoiding smoking, and treating depression—might help protect your brain health. However, this is early research, and you should talk to your doctor about what’s right for your individual situation

The Research Details

This was a narrative review, which means scientists read and summarized many existing research studies on the topic rather than conducting a new experiment. The researchers looked at studies examining estrogen at different life stages—from when girls start puberty through menopause—and how it connects to various health factors that affect dementia risk.

They examined both things you can change (like exercise, diet, smoking, and depression) and things you cannot change (like your genes). They also looked at how birth control pills and hormone replacement therapy (medications that contain estrogen) might affect brain health.

This approach allowed the researchers to see patterns across many studies and identify which connections between estrogen and dementia risk factors have the strongest evidence.

A review like this is important because it brings together information from many different studies to help us see the bigger picture. Instead of relying on one study, scientists can identify which findings appear consistently across multiple research projects. This helps doctors and researchers understand where to focus future studies and what might be the most promising areas for helping women protect their brain health.

This review was published in a well-respected journal focused on Alzheimer’s disease research. However, because this is a review of existing studies rather than new research, the quality depends on the studies reviewed. The authors note that significant gaps exist in the research for most risk factors, meaning we don’t have complete information yet. The findings suggest connections but don’t prove cause-and-effect relationships.

What the Results Show

The research found that estrogen appears to be connected to several health problems that increase dementia risk. The strongest connections were found with three factors: LDL cholesterol (the ‘bad’ cholesterol), smoking, and depression.

For example, estrogen levels may influence how much cholesterol builds up in your blood vessels, which can affect blood flow to the brain. Estrogen might also affect mood and depression risk, which itself is linked to dementia. The relationship with smoking suggests that estrogen may influence whether women start or continue smoking, or how smoking affects their bodies.

The review also examined other important risk factors like high blood pressure, obesity, lack of exercise, hearing loss, and social isolation. While estrogen appears connected to some of these, the evidence is less clear for others.

The researchers found that estrogen levels change dramatically at different life stages—during puberty, reproductive years, pregnancy, and menopause—and these changes might affect dementia risk at different times in a woman’s life.

The review also looked at how sleep, diet, and stress might be affected by estrogen and connected to brain health. Additionally, the researchers examined how birth control pills and hormone replacement therapy (HRT)—medications that contain estrogen—might influence dementia risk. The research suggests these medications may affect some of the same health factors that influence brain health, though more research is needed to understand the full picture.

This review builds on previous research showing that women develop dementia more often than men. Scientists have known for years that estrogen affects many body systems, but this review is one of the first to systematically look at how estrogen might connect to the specific health problems that lead to dementia. The findings support earlier research suggesting that hormones play an important role in brain health, while also highlighting that we still have much to learn about these connections.

The authors clearly state that significant gaps exist in the research. For most of the health factors studied, there isn’t enough research to draw firm conclusions. Many studies were small or didn’t specifically look at dementia risk. Additionally, this review cannot prove that estrogen causes these health problems—it only shows associations or connections. More research is needed to understand whether changing estrogen levels could actually prevent dementia, and at what life stages this might be most important.

The Bottom Line

Based on this research, women should focus on managing the health factors that are clearly linked to dementia risk: keeping cholesterol levels healthy, not smoking, treating depression, managing blood pressure, staying physically active, maintaining a healthy weight, and staying socially connected. These recommendations have moderate to strong evidence supporting them. Regarding estrogen-based treatments like hormone replacement therapy, talk with your doctor about whether these are right for you—the research doesn’t yet show they prevent dementia, but they may affect some related health factors.

This research is most relevant to women concerned about dementia risk, especially those going through or approaching menopause. Women with family histories of dementia, those experiencing depression, or those with high cholesterol should pay particular attention. Healthcare providers should consider this research when counseling women about brain health. Men should also care about this research because understanding how hormones affect dementia risk in women may eventually help us understand brain health in everyone.

Changes in health factors like cholesterol, depression, and smoking can take months to years to significantly impact brain health. Dementia itself typically develops over many years, so protecting your brain is a long-term commitment. You might notice improvements in mood, energy, and overall health within weeks to months of making lifestyle changes, but brain-protective benefits develop over years.

Want to Apply This Research?

  • Track three key factors weekly: (1) mood/depression symptoms using a simple 1-10 scale, (2) smoking or nicotine use (days abstinent), and (3) physical activity minutes. These are the factors most strongly connected to estrogen and dementia risk in this research.
  • Set a goal to address one of the three strongest connections: manage cholesterol through diet and exercise, quit or reduce smoking with app reminders and support, or track mood and depression symptoms to know when to seek help. Start with whichever feels most achievable for you.
  • Create a monthly dashboard showing trends in these three areas. Set reminders to check in with your doctor annually about cholesterol levels and mental health screening. Use the app to identify patterns—for example, whether stress, sleep, or other factors affect your mood or smoking urges—and adjust your approach accordingly.

This review summarizes research on connections between estrogen and dementia risk factors, but it does not prove that estrogen causes dementia or that changing estrogen levels will prevent it. The findings are based on existing studies with varying quality and significant research gaps. This information is educational and should not replace personalized medical advice. Women concerned about dementia risk, considering hormone replacement therapy, or experiencing symptoms should consult with their healthcare provider. If you are experiencing memory problems, mood changes, or other concerning symptoms, seek medical evaluation promptly.