By Sumathi Reddy

Lisa Mosconi, a neuroscientist and director of the Women’s Brain Initiative at Weill Cornell Medical College in New York City, focuses her research on what she says is one of the most under-researched, underdiagnosed and underrated fields in medicine: the female brain and women’s brain health.

In her new book, “The XX Brain,” which comes out March 10, she explains the differences between the female and male brains and explores the different ways the brain affects women’s health. She offers practical tips on how to optimize brain health and discusses the unique risks women have for developing Alzheimer’s disease and actions they can take to help prevent it.

Here are edited excerpts from a recent interview:

How are female brains different than male brains?

There’s some really strong research showing that women’s brains are not the same as men’s brains from the minute we’re born. They’re wired a little bit differently because the DNA is different.

Some parts of women’s brains are better or more interconnected with each other, which has been linked to our capacity to multitask. Not to say that men are not able to, but women seem to have a little bit of an advantage in that department. In the same way women have better verbal memory than men.

But the most important thing that we have shown is that women’s brains age differently than men’s brains and that there are hormones and changes—in particular menopause—which really play a key role here.

You refer to the term “bikini medicine” in your book. Can you explain that?

Bikini medicine is like saying that women are men with boobs and tubes. It’s saying that the only things that makes a woman a woman from a biological and medical perspective are the parts of the body we cover under a bikini. That for a long time meant that medical professionals would diagnose and treat both genders the same exact way. That’s obviously problematic for a number of reasons, but also it led to thinking that women did not need to be included in research.

Today we are required by law to enroll men and women in the studies. But then what happens is that the studies just lump them together. So we still have a series of biases and mistakes in research where there’s this assumption that female physiology is the same as male physiology as long as we’re not talking about reproduction.

What are some of the health conditions and diseases that women are more prone to because of these differences?

Anxiety and depression are much more common in women than men, especially starting in midlife but also really since puberty. And then autoimmune disorders like multiple sclerosis—women are more than three times as likely as men to develop these disorders.

Women are four times more likely than men to have headaches and migraines. Women are way more likely to even have a brain tumor, and again especially around menopause. Women are more likely to die of a stroke when they have a stroke. And on top of all that, at the core of my research is women are more likely than men to be diagnosed with Alzheimer’s disease.

What happens to the female brain around the time of pregnancy?

We always think about aging as a kind of linear trajectory. But for women’s brains it’s more about bumps. There are three big bumps in the road. There’s puberty, when you have an explosion of hormonal power and your brain is just really becoming an adult brain. And then there’s pregnancy, where again we have this huge surge of hormones, which then leads to a crash after the baby is born. And then menopause later on, which is pretty much a decline in hormones.

Brain imaging studies done in women before and after pregnancy show that some parts of the brain kind of shrink after the baby is born, and that this shrinkage is actually probably a good thing. It’s more like an adaptive thing. The new mom is like, “OK, I no longer have time for everybody’s things. I need to be able to focus on this baby and I want to optimize my brain so that it’s really sharp and really devoted to motherhood.”

What about before and during menopause?

We have done a number of brain imaging studies to look at what really happens during the transition. What we have shown is that on average, women who are going through menopause show progressively reduced brain energy levels.

At the same time, for some women, not all women, we find the emergence of amyloid plaques or Alzheimer’s plaques in their brain during menopause. We don’t find that in men of the same age.

Is declining brain energy bad? What does that mean exactly?

We know that reductions in brain energy levels are often a red flag for Alzheimer’s disease. I’m kind of ambivalent about defining it as good or bad because it is a transition. If it goes back up after menopause, then it’s fine. If it keeps declining and the woman also is developing Alzheimer’s plaques, then that’s when I would start thinking about Alzheimer’s prevention and a thorough medical checkup.

We need to follow these women over time even more to really understand what happens.

Let’s talk about Alzheimer’s disease. Why does it affect two times as many women as men?

For a long time people would say Alzheimer’s is a disease of old age and women live longer than men and that’s why more women than men have Alzheimer’s. We have challenged that belief. Alzheimer’s starts with negative changes in the brain decades prior to clinical symptoms. What we have shown is these changes in women really overlap with menopause. Women tend to develop Alzheimer’s earlier than men in their brains. But there could be a number of different factors as well that really lead to compounded effects.

What can they do about it?

There are many risk factors for Alzheimer’s that are not genetic in nature but are really related to the choices we make in life.

A healthy diet is very important for women, especially making sure that the diet contains antioxidants. There’s been studies showing how dietary intake of antioxidants like vitamin C, vitamin E and beta-carotene are correlated with higher brain energy in women.

Exercise has been shown to possibly protect against brain aging and Alzheimer’s in both men and women, but it seems to be even better for women. If you’re a middle-aged woman and you exercise, then your risk of dementia is 30% lower compared to a middle-aged woman who does not exercise.

Another big one is stress. Studies have shown that if you have chronic stress, that really impacts brain aging.

What are some tests you recommend that women get to learn more about cognitive health and brains?

Genetic testing is a little controversial because you need to have counseling together with the testing. There are other tests, however, that are easy to do and they’re very helpful. You need to know your metabolic activity. You need to know your lipids, for example, your cholesterol levels, your triglycerides. We need to know our insulin levels. You need to know if you’re overweight.

Hopefully one day brain scans will be part of a women’s medical checkup starting in midlife, because we really need to have a baseline.

Do you recommend hormone replacement therapy around perimenopause and menopause?

For a long time people were all over hormonal therapy, then for a long time everybody was terrified of hormonal therapy, and we’re testing it in a more thoughtful way. Many of us are testing different dosages, different formulations, and importantly, different timelines. Should we start earlier? What kind of dosage would be best? And when do we stop? I think we need more work to really fully understand the benefits of hormonal therapy and the downsides as well. But the important thing is it should be individualized.