It was as recently as 1992, says Dr Lisa Mosconi, that scientists discovered that oestrogen and testosterone, hitherto thought of as sex hormones, had an integral part to play in brain function. Women’s brains, says Dr Mosconi, use more oestrogens than male brains, which use more androgens (a category that includes testosterone). Of these oestrogens, says Dr Mosconi, “oestradiol is the most potent form. It pushes your neurons to burn glucose to make energy. So if your oestradiol is high, your brain energy is high, and at the same time your immunity is high and your neuroplasticity” – essentially your ability to learn new skills – “is also high”.
Dr Mosconi, a neuroscientist who is the author of The XX Brain and the director of the Women’s Brain Initiative at Weill Cornell Medicine, says that testosterone declines only slowly in men as they age, meaning that they can reproduce in their 70s and occasionally beyond. “Look at Mick Jagger!”
But for women, she warns, “oestradiol declines very sharply in midlife during the transition to menopause. This change is not just the cue for stopping being able to have children, but also that something is changing inside your brain. Your energy metabolism changes, your neurons slow down, some women start ageing faster.”
The bad news continues. Dr Mosconi and her colleagues have shown that this change is associated with the accumulation of Alzheimer’s plaques in women’s brains.
In summary, says Dr Mosconi, “it’s important for women to understand that there’s a strong connection between oestrogen activity and brain longevity, and that there are things that we can do to really support our hormones and their effect on brain health.”
What does Dr Mosconi advise that women do? Short of hormone replacement therapy, which can be prescribed during or near menopause to redress an oestrogen shortfall, there are many ways of supporting long-term healthy hormone function. Dr Mosconi says that it’s important to have a good supply in your diet of omega-3 fatty acids, suggesting fish, supplements, and flaxseed oil, of which “one tablespoon daily is more than half of the omega-3s you’ll need that day”.
Dr Mosconi also recommends eating foods that contain phytoestrogens – compounds that mimic oestrogen and are found in plants. “There’s something beautiful about oestrogen in that it’s the most ancient of hormones, so it can go across species… so the oestrogens a flower makes can be imported into our own bodies and will have a very similar effect as our own oestrogens, except milder,” she says.
Sources of phytoestrogens, she says, include flaxseeds, sesame seeds, chickpeas, dried apricots, legumes, strawberries, mango and cantaloup. And dark chocolate – “it’s not a great source of oestrogens, but it does contain some,” adds Dr Mosconi.
Finally, she says, avoid plastic where possible. Bisphenol A (BPA), a chemical that is present in many plastic products, is an example of a xenooestrogen: a chemical “that mimics the effect of oestrogens in the body, but in a very negative way”. Eat off ceramic plates and drink out of glass containers instead, and definitely don’t heat plastic containers in a microwave.