As we age, hormones change in dramatic ways that can alter our mental and physical health—and the science around those hormones is changing too.
A new study just published in the journal Neurology sheds light on the ways estrogen may protect the brain as it ages, and the results are promising.
The research examined the health outcomes among 352 cognitively unimpaired women who underwent a brain MRI at age 70 and again five years after the first scan. Out of the group, women who had longer lifetime exposure to estrogen through oral birth control and menopausal hormone therapy showed fewer physiological markers associated with Alzheimer’s disease and had healthier brains overall.
Scientists have already established a connection between longer reproductive spans—basically, the number of years after menstruation starts and before it stops—with reduced brain aging later in life. That research and other findings suggest that estrogen has a strong neuroprotective effect, basically working as armor for the brain against cognitive decline. But as women age, their estrogen levels begin to decline, lowering the hormonal barrier that protects the brain during the body’s reproductive years.
Giving the brain a boost
Estrogen supports cognitive health in a number of ways, including reducing inflammation, boosting blood flow, and protecting the brain’s white matter—the connective tissue that works as a superhighway between neurons.
“The long-term impact of endogenous and exogenous estrogen fluctuations on late-life [cerebral small vessel disease] severity remains poorly understood,” the paper’s authors wrote. That condition is associated with cognitive deterioration and Alzheimer’s, a devastating disease that is almost twice as common in women as in men.
“Previous studies have linked longer reproductive span, earlier [periods], and later menopause to reduced brain aging, reinforcing the neuroprotective role of estradiol,” the authors wrote. “While longer lifetime estrogen exposure may provide neuroprotection, abrupt estrogen loss may increase neuropathology accumulation and dementia risk.”
The new research is important because it shows a link between external or “exogenous” sources of estrogen and improved brain health. While doctors can’t dictate how long a person’s brain might be protected by naturally occurring endogenous estrogen, exogenous estrogen can be sourced from oral medications (including birth control pills), transdermal patches and gels, injections, and topical creams.
A changing story about estrogen
The conversation around estrogen has been in the midst of a seismic shift.
A year ago, the U.S. Food and Drug Administration initiated the removal of black box warning labels from hormone-based drugs used to treat perimenopause and menopause symptoms.
The stern safety warning was first put in place more than two decades ago, cautioning clinicians and causing panic among patients that estrogen-based drugs could raise the risk of serious medical issues, including heart attacks, blood clots, and breast cancer. For years, that official guidance prevailed, in spite of evolving research showing that many patients can benefit from and use these medications safely.
In response, estrogen is undergoing something of a renaissance. More people are talking openly about what they experience during menopause and perimenopause (the hormonally chaotic phase before the body fully moves into menopause). For many women, those hormonal changes crash into their personal and professional lives with an array of mood and physical symptoms that go well beyond hot flashes.
The changing discourse has been a boon for telehealth providers like Midi as a whole generation of women explore the fact that a simple patch, pill, or gel might boost their quality of life considerably.
“With few exceptions, there may be no other medication in the modern era that can improve the health outcomes of women at a population level more than hormone replacement therapy,” former FDA Commissioner Marty Makary said last year, extolling the long-term benefits of hormone therapy as “tremendous.”
The promise of relief for symptoms like brain fog, hot flashes, depression, and anxiety has been enough to drive a nationwide shortage of estrogen patches. As new research delves deeper into the ways that estrogen may protect the aging brain, many women will have one more reason to hit up their doctor for a chat about hormone therapy.
