Episode 530: The Surprising Science Of The Dad Brain
August 25, 2026 by Justin Lehmiller
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Becoming a parent changes just about every aspect of life. But it doesn’t just change your routines, priorities, and relationships—it can actually change your brain and body. And while we’ve long recognized the profound biological transformation that accompanies motherhood, we’re only beginning to understand what happens to men when they become fathers. So what exactly is a “dad brain?” How does fatherhood reshape the male brain, hormones, and even the body?
My guest is Darby Saxbe, a clinical psychologist and tenured full professor of psychology at the University of Southern California. She has published over eighty scientific articles in peer-reviewed journals. Her research focuses on the transition to parenthood, particularly the neural and hormonal underpinnings of fatherhood. Her latest book is titled Dad Brain: The New Science of Fatherhood and How It Shapes Men’s Lives.
Some of the specific topics we cover include:
- How (and why) does becoming a parent change the brain?
- How similar are “dad brain” and “mom brain?”
- What happens to testosterone when men become fathers?
- Is there a biological reason for the “dad bod?”
You can visit Darby’s website to learn more about Dad Brain and follow her on Instagram @darbysaxbephd
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Credits: Precision Podcasting (Podcast editing) and Shutterstock/Florian (Music). Image created with Canva; photos used with permission of guest.
Dr. Justin Lehmiller
Founder & Owner of Sex and PsychologyDr. Justin Lehmiller is a social psychologist and Research Fellow at The Kinsey Institute. He runs the Sex and Psychology blog and podcast and is author of the popular book Tell Me What You Want. Dr. Lehmiller is an award-winning educator, and a prolific researcher who has published more than 50 academic works.
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