This post is a short section from my book, The Estrogen Fix. As you will see, hot flashes are more than just a nuisance; they affect your brain…
Hot flashes are one of the most common symptoms of and complaints about menopause. Sure, they are annoying, embarrassing, and disruptive. But do they do something much more sinister? Do frequent hot flashes contribute to aging in the brain? Do they leave the female brain more susceptible to aging? Could hot flashes lead to frequent reductions in bloodflow that in turn damage the brain in the way poor bloodflow to the heart leads to cardiac damage? Could they reduce the number of neurons in the brain, particularly in the hippocampus, setting a woman up for Alzheimer’s disease?
Some researchers think hot flashes do all these things, which is another reason why women and their doctors need to know about the estrogen window. In addition, women who have surgical menopause have suicidal thoughts twice as often (10%) as women who go through natural menopause.
Women with low estrogen levels caused by removal of their ovaries were found to have memory impairment due to hot flashes. In a separate study using single proton emission computed tomography (SPECT) scans of healthy menopausal women, hot flashes were associated with reduced cerebral bloodflow, and bloodflow is essential to brain health, as described previously. The regions of the brain affected by hot flashes were the same areas where Alzheimer’s disease can be seen on a scan. Once the women participants received ET, the hot flashes stopped and cerebral bloodflow returned to normal.
This is particularly important because the volume of the brain and/or its weight naturally reduces at about 5 percent per decade after age 40, and after age 70, brain volume declines even faster. There are gender differences; men tend to lose volume in their frontal and temporal lobes, whereas women tend to lose volume in their hippocampus and parietal lobes. The natural loss of brain volume combined with not being treated with HT seems to be one of the major contributors to Alzheimer’s disease, which is more common in women than in men. Women treated with ET (estrogen therapy) and EPT (estrogen progesterone therapy) within their estrogen window have not been found to have the same increased risk of Alzheimer’s disease as menopausal women not treated with these hormones. It is interesting that one of the major reasons for men having less Alzheimer’s disease is that their brains have more estrogen.
That’s right; men have higher testosterone levels, and both men’s and women’s bodies can turn testosterone into estrogen by a process called aromatization. As a result, men over the age of 60 have approximately three times more circulating estradiol than women of the same age. It’s the reason why men don’t begin to lose brain volume until about a decade after women 30–at age 60.
All these studies help to explain the work of Stanford University researchers who found that estrogen improves verbal memory in postmenopausal women aged 49 to 68. One of the more interesting parts of this study was that the bioidentical estrogen estradiol resulted in significantly better verbal memory performance compared to women receiving conjugated estrogen, although both types of estrogen have been found to improve both verbal and nonverbal memory when compared to a placebo. During this study, women given estrogen for 21 days showed increased activation of their brains when studied with positron emission tomography (PET) scans. It’s easy to imagine that having better verbal and nonverbal memory could have a major positive impact on how women feel about themselves because they feel sharper, less foggy, and better focused, qualities that also impact how they are viewed by their family and friends and how they perform at work. Even using estradiol for only 2 to 4 months has been shown to improve verbal memory in woman younger than 65.
So the take home message is…hot flashes and low estrogen impair women’s brain function. And stopping hot flashes and taking estrogen is one way to improve it.
More information on estrogen and menopause symptoms can be found in The Estrogen Fix.