The researchers analyzed post-mortem data from 21,462 participants, comparing 258 women who reported estrogen-only MHT use with approximately 2,701 women who reported no MHT use.<\/p>\n
The researchers examined the brains for signs of Alzheimer\u2019s disease<\/a>, including amyloid plaques, neurofibrillary tangles and amyloid-plaque density. Plaques and tangles are two hallmark brain changes associated with the common dementia.<\/p>\n ALZHEIMER’S BLOOD TESTS MAY PREDICT SYMPTOMS YEARS IN ADVANCE, BUT EXPERTS URGE CAUTION<\/a><\/p>\n The women who took estrogen-only therapy \u2014 most of whom had likely undergone hysterectomies \u2014 were found to have a 35% lower chance of Alzheimer\u2019s pathology and 39% lower odds of dementia over a lifetime.<\/p>\n Women who used estrogen-only menopausal hormone therapy (MHT) were less likely to develop Alzheimer\u2019s-related brain changes or dementia. (iStock)<\/p>\n Among some living participants, estrogen-only users also performed better on memory testing<\/a> and were better able to function independently, the study found. Biomarkers in blood and cerebrospinal fluid supported these results.<\/p>\n The participants averaged 70 years of age.<\/p>\n Recent research indicates that menopausal hormone therapy may offer greater benefits when started during or shortly after menopause, the researchers noted.<\/p>\n HOW EATING HABITS COULD INFLUENCE PARKINSON\u2019S DISEASE RISK, ACCORDING TO EXPERTS<\/a><\/p>\n Because the women in the study were generally older when they began treatment, the results may actually understate the potential benefits of earlier therapy.<\/p>\n These findings appear to contradict prior studies that linked menopausal hormone therapy<\/a> to increased dementia risk.<\/p>\n Alzheimer\u2019s disease is the leading cause of dementia among older adults, with women comprising about two-thirds of diagnoses. (iStock)<\/p>\n “Estrogen has well-described neuroprotective effects<\/a> in animal models,” co-author Jennifer Bruno, PhD, an instructor in psychiatry and behavioral sciences, told Fox News Digital.<\/p>\n “Estrogen plays a role in shifting amyloid toward the non-amyloidogenic pathway and promoting tau dephosphorylation \u2014 both amyloid and tau are hallmarks of Alzheimer\u2019s disease.”<\/p>\n DAILY EATING HABIT LINKED TO BETTER BRAIN HEALTH IN OLDER ADULTS, NEW RESEARCH SUGGESTS<\/a><\/p>\n “Additionally, estrogen supports synaptic plasticity<\/a>, reduces neuroinflammation and supports blood brain barrier integrity. So, finding less AD pathology in estrogen-only users was consistent with this mechanism.”<\/p>\n Memory can be impacted by many different conditions, which means clinical diagnoses<\/a> can sometimes be unreliable, the researchers noted.<\/p>\n Recent research indicates that menopausal hormone therapy may offer greater benefits when started during or shortly after menopause. (iStock)<\/p>\n “Although there\u2019s been great progress with bloodborne and cerebrospinal fluid biomarkers, they don\u2019t tell you the amount and precise location of the brain damage,” said senior author Hadi Hosseini, Ph.D., an associate professor of psychiatry and behavioral sciences at Stanford.<\/p>\n “By looking where the actual damage is done \u2014 the brain \u2014 you can see where the Alzheimer\u2019s-associated defining features are and how many of them are there.”<\/p>\n CLICK HERE FOR MORE HEALTH STORIES<\/a><\/p>\n The study did have some limitations, according to the researchers. As it was observational, it could only show an association but could prove that the hormone therapy reduced Alzheimer\u2019s risk.<\/p>\n “It\u2019s possible that women who used hormone therapy differed from non-users in ways we couldn’t fully measure, such as baseline health status or engagement with healthcare,” Hosseini told Fox News Digital. “We worked hard to adjust for known confounders and to account for who does and doesn’t come to autopsy, but observational data can only take you so far.”<\/p>\n CLICK HERE TO SIGN UP FOR OUR HEALTH NEWSLETTER<\/a><\/p>\n Alzheimer\u2019s disease is the leading cause of dementia among older adults<\/a>, with women comprising about two-thirds of diagnoses.<\/p>\n “By looking where the actual damage is done \u2014 the brain \u2014 you can see where the Alzheimer\u2019s-associated defining features are and how many of them are there.”<\/p>\n While the study findings don\u2019t change current clinical recommendations, Hosseini said they highlight the need for well-designed clinical trials to confirm these observations and to determine whether menopausal hormone therapy has a protective cognitive effect.<\/p>\n TEST YOURSELF WITH OUR LATEST LIFESTYLE QUIZ<\/a><\/p>\n “These results add meaningful, first-of-their-kind pathological evidence to a genuinely controversial area \u2014 but they are a signal for further study, not a reason to start or stop MHT for brain health,” Bruno added.<\/p>\n “We need prospective, biomarker-based trials that follow women<\/a> before, during and after menopause to understand the effects of MHT on brain health.”<\/p>\n![\"Woman](\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2026\/08\/woman-hormone-replacement-therapy.jpg\")
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