Did you know that March 10-March 16th is Brain Awareness Week? It’s an opportunity to promote and highlight important brain research, an area of scientific inquiry that continues to evolve and produce important new understanding of how the brain works and what happens as the brain ages. In celebration of this important work, we’re going to highlight several new studies of particular relevance to older women specifically and older adults more generally.

Within the past couple of weeks, several new studies have been published focusing on the brains of older women and how the unique chromosomal makeup of women may benefit their brains, while at the same time recognizing that menopause and hormonal therapy may have a negative impact. First, it’s important to understand that there has been a lag in focusing on how sex differences affect biomedical research generally and women’s brain health in particular. We already know that women are more likely than men to develop Alzheimer’s (⅔ of Alzheimer’s cases are women, perhaps because women tend to live longer), and being a woman is considered a risk factor for developing dementia. Yet, from new research, we also know that being biologically female may have some benefit when it comes to brain aging. Women have 2 X chromosomes while men have 1 X chromosome and 1 Y chromosome. What this new research, published in Science Advances (and conducted in mice), reports is that the second X chromosome that women have appears to “wake up” around the time women reach age 65 and begins to express genes that strengthen the brain’s connections, benefiting cognition. Scientists discovered that one gene in particular- associated with the flow of information back and forth in the brain- could also boost the brains of male mice if it is separately given to them. So, not only did this research highlight the resilience of the female brain, but it also set up a path to future research to explore new treatment possibilities for men’s aging brains as well. 

Several additional studies have raised questions and concerns about the role of menopause and the use of hormonal therapy when it comes to brain aging in women. One new study, also published in Science Advances, looked at the connection between the onset of menopause and cognitive decline in women. Using clinical records and autopsy data, researchers examined whether an earlier start to menopause (around age 45) would worsen brain functioning in older women, possibly due to the drop in estrogen associated with menopause. The results did not appear to support that conjecture, though they found some vulnerabilities in the brain synapses of women who began menopause early. However, the study results were considered weak and perhaps even unreliable. However, a third study published in Science Advances looked at the use of hormone therapy(HT) to address menopausal symptoms and whether that therapy affected the brains of older women. What the researchers found in this observational study was that in women over 70 who had received HT, there was a greater accumulation of Tau (a potential hallmark of Alzheimer’s disease) than in women who did not have HT. While that doesn’t mean that hormone therapy increases the risk of an Alzheimer’s diagnosis, it does underscore the importance of conversations about its risks and benefits and supports the current clinical guidelines of providing HT as early into menopause as possible. For more on this study, look here. And for a recent study examining the number of menopausal symptoms a woman has and its relationship to cognitive decline (and the potential positive role of HT), get out your fan and read here.

Finally, 2 recent studies in mice have found an association between your diet and your aging brain health. In one study, researchers found that after only 3 days of eating junk food, brain changes can be set in motion to facilitate weight gain, diabetes, and other metabolic diseases. So put down your Doritos and read more here. The second study of a high-fat diet, often found in fast food, reports an association between 3 days of high-fat eating and memory decline in older adults, regardless of whether obesity is involved. For more on this study, prep your salad and click here.