Women and children first, right? The idea that the female body is more vulnerable is pervasive in the public imagination. But in biology, it is increasingly clear the male body has that dubious honour. So let’s talk a bit about innate female strength, shall we?
When it comes to fighting off invading pathogens, female bodies come up victorious – and not just in relation to . Across the human lifespan, are less likely to contract most infections. At first, scientists weren’t sure about this: in many places in the world, boys are taken to health clinics sooner, . But the signal we see is too strong, and it holds in many lab animals, too. Female animals are simply more resilient – . That is when all sorts of bodily mayhem happens, much of which can cause the risk of death to outpace that of .
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But barring pregnancy and the postpartum period, female resilience holds true. We know that in many , , males tend to die sooner than females, but on the way, more often. This is usually chalked up to them having a single X chromosome instead of two, making X-linked mutations more potentially malignant as these wouldn’t be kept in check by a non-mutated partner. But female resilience seems to function at nearly every tier of a body’s organisation. It even influences how individual cells decide whether or not to stay alive, which can really matter when those cells are part of the brain.
People with mild to moderate traumatic brain injuries (TBIs) fare worse if they are female, for example, but those with severe TBIs do worse if they are male. This is something we are just starting to learn, in part because people who experience intimate partner violence are both more likely to be female and than the average person.
One reason might be that male brains tend to respond to the necrotic death of their injured cells a bit differently, with the whole brain . Male cells also have , making them more vulnerable to damage from free radicals, which can lead to malfunction and cell death. For doctors in emergency care, the outcomes of these differences can be striking: often don’t do as well as female ones, and this has been seen in rodent models, too.
Well, that’s the case so long as the menopause hasn’t happened, when the female body becomes than the male one to things like severe ischemic stroke – technically not a TBI, but a condition that should, in principle, follow similar patterns in terms of lesion severity and brain-wide inflammation. Yet those who are post-menopausal often do worse after a stroke. Before menopause, they are protected, perhaps because of their higher estrogen and progesterone profile, which is already , for example, many types of tissue damage.
A number of labs are testing whether treating male TBI patients with female sex hormones might help them stave off some of the damage. There are outstanding questions: which hormones will help, how much should be used, when should they be given and at what point in the body. These are a hot topic of applied research for skin injuries, too. Female patients who are pre-menopausal tend to heal lacerations faster, and adding healing in both sexes. The solution, in other words, to helping male patients stay alive and healthy might just be making their bodies – temporarily, locally, in a controlled fashion – be more female.
This is hardly the story we usually tell about the sexes. Maybe the boys should get in the life rafts first? For their safety.
Cat Bohannon is the author of Eve: How the female body drove 200 million years of human evolution
