Dad Brain: The New Science of Fatherhood and How it Shapes Men's Lives

by Darby Saxbe

A groundbreaking exploration of how fatherhood transforms men’s brains, bodies, health, skills and relationships

In recent years men’s attitudes to fatherhood have changed dramatically. But only now are we learning how profoundly fatherhood changes men’s brains and biology – and the effects these changes have on their health, skills, relationships and sense of purpose.

In Dad Brain, one of the world’s leading researchers of fatherhood, Darby Saxbe, provides a captivating account of this new science, packed with insights into how different approaches to fatherhood affect not only men but the whole family. Among its many revelations are

Fathers’ brains shrink and their testosterone drops
Fathers undergo a host of hormonal changes once thought only to affect women
Fathers can suffer post-partum depression but enjoy better long-term health
Fathers’ style of play makes their kids more resilient
Dads who do more housework are generally happier

Above all, Dad Brain shows that men are wired to participate in care just as women are, but that many of these adaptations only come online when fathers invest time into the more they do, the more they change for the better. Ultimately it shows a good father is not something you are, it is something you become.

‘Entertaining and fascinating … a must-read’ Eve Rodsky
‘A wonderful book … from an accomplished scientist’ Antonio Damasio
‘Masterful, science-packed, offering unique and practical insights’ Daniel J. Siegel

Darby Saxbe 2026 (P) Penguin Audio 2026

Genres: Parenting, Nonfiction, Psychology, Science, Fatherhood, Audiobook, Health

Audible Audio

Published June 11, 2026

Reviews

[Michael · Rating 4 out of 5]

Being a father shrinks your brain, lowers your testosterone levels, promotes weight gain, and increases any marker of biological or psychological stress you care to check.

It is also one of the best and most fulfilling things a man can do for himself and the greater good.

Somehow, this book convinced me of both these things. Maybe I didn't need convincing... I'm a father of young kids myself, and spent half this book making internal shrieks of validation as the author describes the various challenges and tensions of fatherhood that any dad knows all too well. I'm the prime audience for this sort of thing.

Great, transparent, evidence-based discussions of the physical and emotional effects of fatherhood on men, as well as the historical trajectories of expectations of fathers. There is certainly an argument at the core for more direct involvement of fathers in childcare, but it's well-supported, balanced, and takes account of the many situations and contexts that have defined both historical and modern parenthood. It felt direct but not preachy on this point, but if you're looking for a validation of a workaholic, detached, uninvolved style of fatherhood, you won't like what the author has to say.

In the end, it's a great read if 1) you are a father or 2) you know a father. I think that includes most of us.

4.5 / 5

[Austin Schroeder · Rating 4 out of 5]

This book was really interesting. It wasn’t quite what I was expecting as I thought it would be a manual on how to be a good father. While there was a lot of good information on what can make a good father if actually went more into all aspects of fatherhood from a scientific perspective, cultural perspective, and more. It was really interesting and a book I will be recommending to my friends that are fathers.

One other thing: I would often go to my wife with information from this book saying “did you know …” and I would often get a response of “this is not what I expected you to learn from this book” which was very fun for me :)

[Frederic · Rating 3 out of 5]

Overall, I found this a pretty solid, up-to-date summary of the small, but quickly growing research on how “fatherhood” shapes and is shaped by biological, situational, and cultural factors. For a book called “Dad BRAIN”, I was hoping for a deeper, more involved discussion on the neural modulations. They are in there, in a chapter and here and there, but could have been more extensive for my taste. Still, this was interesting, inspiring, and let’s say reaffirming.

[Abigail Franklin · Rating 4 out of 5]

Great, great stuff. Loved the line about being less concerned with “mothering” and “fathering” but rather focusing on *parenting*.

[Colin Burke · Rating 4 out of 5]

That was really good. A dissertation on Dads 🥲

[Savannah Smith]

Dad Brain by Darby Saxbe is an insightful and engaging nonfiction book that explores how fatherhood changes the male brain emotionally, psychologically, and even biologically. Drawing on neuroscience, psychology, and personal stories, Saxbe challenges outdated stereotypes about parenting and presents a compelling argument that fathers undergo meaningful brain and behavioral changes when they become actively involved caregivers.

One of the book’s greatest strengths is its accessibility. Although the subject matter is rooted in scientific research, Saxbe explains complex concepts in a clear and relatable way. She combines research findings with real-life examples, making the material feel practical and emotionally relevant rather than overly academic. Readers do not need a background in science to understand or appreciate the ideas presented.

The book also stands out for its balanced and modern perspective on fatherhood. Saxbe emphasizes that caregiving is not determined solely by gender but is shaped by involvement, emotional connection, and environment. She discusses how active parenting can influence hormones, stress responses, empathy, and emotional regulation in fathers, highlighting the importance of shared parenting roles within families.

Another strength is the book’s compassionate tone. Rather than criticizing traditional parenting expectations, Saxbe thoughtfully examines how social pressures and cultural norms affect fathers and families. The discussion of mental health, work-life balance, and emotional bonding adds depth to the book and makes it relevant to modern parenting conversations.

At times, the book becomes somewhat repetitive, particularly when revisiting similar research themes throughout different chapters. However, the engaging writing style and meaningful insights help maintain reader interest.

Overall, Dad Brain is an informative and thought-provoking exploration of the science of fatherhood. Darby Saxbe successfully combines research with empathy, offering readers a fresh perspective on parenting, emotional development, and family relationships. The book is highly recommended for parents, healthcare professionals, and anyone interested in psychology, neuroscience, or modern family dynamics.

[Kelsey Noah · Rating 5 out of 5]

Great stuff. I’ve read a lot about the transformative process of motherhood and what mothering does to a person’s mind, body and spirit. However, I’ve never read about what parenting does to men. I wholeheartedly agree with the author that we must remove the gender barriers of caregiving policy to benefit all parents of all kinds because children and our society benefit. I must give a shoutout to @joshnoah because he told me about this book and he is also an outstanding dad!

[Brad Dell · Rating 5 out of 5]

As a new dad struggling with depression and isolation, this book felt so very affirming, comforting, securing. The research is fascinating and unique, and corrects a great many misunderstandings. I wish more would read this so we could realign understandings of how both mothers and fathers struggle together (though unequally, of course) yet also find vast beauty in that shared journey. Maybe more men would stick it through, then, and be vulnerable in the process.

[Ethan Taylor · Rating 4 out of 5]

I’m all for year long paternity leave

[Brahm]

DNF. I find I have no patience for popular science books, which Saxbe describes this one as in the intro.

It started out promising and engaging but after picking it up and putting it down a few times, by page 70 I realized I had zero interest in whatever came next. Which is too bad as this is an interesting topic, but there was too much fluff for me.

[Travis · Rating 3 out of 5]

3/5 stars

Dad Brain is an interesting and well-researched book, especially for the many studies and scientific details it brings together about fatherhood, caregiving, hormones, bonding, and longevity. I found a lot of the research genuinely fascinating, including the idea that caregiving can come before bonding, the concept of post-traumatic growth, and the distinction between attachment and activation, where fathers often play a key role in encouraging exploration and healthy risk.

That said, the book’s breadth is also part of its limitation. Much of the evidence comes with caveats, conflicting findings, or qualifications, which makes the overall argument feel less forceful than it could have been. Saxbe makes a compelling case that parenting and fatherhood can bring meaning, purpose, and even mental and physical health benefits to men’s lives, but I was surprised by how little attention the book gives to the benefits children, especially boys, receive from having a father in the household.

I also thought the book sometimes treated motherhood as the baseline and fatherhood as the deviation. It seems more interested in how men can be drawn into care work on terms that resemble maternal caregiving, while spending less time on the possibility that care work itself might look different, and still be valuable, when shaped by fathers. The discussion of testosterone and men’s mental health also felt somewhat too cautious in downplaying potential benefits.

Overall, Dad Brain is thoughtful, often interesting, and worth reading, but it would have been stronger with a clearer moral vision of fatherhood and masculinity. Even with those limitations, the book makes it clear that fathering matters.

[Jacob White · Rating 3 out of 5]

I believe the absent and isolated father is the greatest threat to our current society. This book is well-researched, repetitive, and can help dads feel seen in some areas while highlighting secular fatherhood. The book does provide a few examples of social changes that need to improve but fails to use the research to help individual dads and communities with this problem.

[M · Rating 4 out of 5]

Definitely reflects a lot of my own lived experience. Totally worth reading.

If you plan on having children, read this. If you don’t, read this. Either way, there are important take-aways from longitudinal neurological and well-being studies that are really helpful to consider.

[Kenny Schwarz · Rating 4 out of 5]

A very good book for highlighting the importance of fathers and the impact they can have on their children. Moreover the book does a great service in examining the physical and psychological changes men encounter when moving into this very important role. As a fathers myself I greatly appreciated that acknowledgement that while when it comes to transitioning into parenthood women are (and deserve to be) the star of the show, many of the tremendous changes men undergo are not trivial.

While the core of this book seemed at times repetitive, the message was an important one and very validating for dedicated dads of the important mission that we serve. Four stars for Dad Brain!

[Teague Broquard · Rating 5 out of 5]

Such a great and encouraging book! Dads, your brain is so cool and will help you rise to the challenge of parenting.

[Ben Crews · Rating 2 out of 5]

I really wanted to like this book and there were parts of it that were really wonderful. But it was way to much pop psychology watered down and it read like it couldnt decide if it was a book or a weird lit review. I think the heart of the first chapter was really great and honestly very meaningful, but just not really well written. It was however quite short so I did finish it, and there were some good parts in there.

[Michael Kokias · Rating 3 out of 5]

My knock against this book isn’t that it is shallow, because it definitely isn’t. It is exhaustive and sharp when it comes to the biological and sociological changes that men experience when becoming dads. And some of that scientific theory is absolutely fascinating. But as a new dad, I was really hoping for Saxbe to take that next, more provocative step of identifying what fatherhood can and should be. While the author had no problem getting political when it came to putting down the manosphere for all its toxic representations of masculinity and fatherhood, she then didn’t take the next step of identifying what a positive version of it would be beyond broad characterizations of latte dads, and what I felt was missing was how men could and should navigate this paradigm socially and interpersonally with their partner/family.

I think this is a book that will be credited for encouraging better conversations, even when it doesn’t live up to them.

[Scott Milam · Rating 5 out of 5]

Loved it, would read another similar book happily

[Jose · Rating 5 out of 5]

Saxbe's book and her research is fantastic in exploring the changes that happen in the brains of new dads.

Overall, the main message of the book is: The birth of a child changes a dad's life. The research shows that it can improve your life in so many ways, IF you let it.

All these great changes only happen IF you get involved. If you become an involved dad with your baby, if you can afford to take a good paternity leave to bond with your baby. If you're willing to put in the effort at night and during the day to be an equal co-parent with our partner. If you're willing to pull back on other things in life, and spend lots of quality-bonding time with your family.

I find that a lot of her research is just the tip of the iceberg. There's much more research that could be done for new dads, and I hope that this book will help fund and bring that research into more light.

I liked that the book was easy to read and understand. It wasn't a research paper. It wasn't full of technical jargon or made the ideas over complex. Saxbe was straightforward with her writing, summarizing what different studies or research has found. It's an approachable book for anyone to read.

I especially enjoyed reading this during my paternity leave of my first-born baby. It happened to be released the same summer that my baby was born. I saw Saxbe promoting her book in podcasts and found my library had a copy.

For anyone that is thinking of becoming a dad, wondering about the changes that might occur, pick up this book. You'll learn a lot and won't regret it.

[bird · Rating 3 out of 5]

i read this because i felt as a non-gestating gay mom it's probably the closest i can get to learning about What's Happening To Me Neurologically these days. the inherent rehabilitation (programs teaching men it's good to love their children etc) of men's support services is depressing and she is sometimes quite Good Man-pilled ("there's so many initiatives to get women into stem but there's even fewer men in care services than women in stem and where are the initiatives for them" is a crazy take! also, we need more initiatives to get men into the care services in part because social workers are all women and maybe that's why men lose custody cases?? what???? women make up a third of judges, who are the ones who determine custody cases. anyway) but also very thoroughly researched; the first half of the book was genuinely great. i appreciated how clear she was about what scientific studies can and can't imply, as well as all the complex overlaps and unknowns esp on a gendered basis pointing to everyone's eternal capacity to change.

the sociocultural analysis of part two is significantly less great. it's also pretty parent-pilled, and i say this as a parent.... but it is not really carrying any kind of load to argue that loving others is good for people lol. this also runs into the problem every book has where it's like "imagine if we did things differently! okay let's do it!" yeah for sure let's. i would love doing things differently, personally.

[Jonathan Mckay · Rating 3 out of 5]

**The Evidence Stops Short**

There is little here that will feel groundbreaking to someone who is already a dad. The brain is plastic. Hormones will mess you up, though not in any linear or intuitive way. The science supplies mechanisms for experiences that fathers already know from the inside.

A more interesting argument emerges underneath the neuroscience. *Dad Brain* becomes an argument about caregiving as a universal human capacity and desire that society has made increasingly gendered. Saxbe's case for de-gendering care reminds me of Ruth Bader Ginsburg pursuing women's equality through cases involving men: make visible how the same system constrains both sexes, then attack the distinction itself. The book is strongest when fatherhood becomes evidence that care was never naturally women's work.

I appreciated this as an overview of the evidence, but it is dispiriting how little evidence there is. I also wanted the book to become more normative about what being a dad should mean. A literature review can tell us that fathers change, that caregiving changes them, and that our institutions lag behind both facts. It cannot tell us what fathers owe their children, partners, or themselves.

[Matthew Rudland Barfoot · Rating 4 out of 5]

This book is great at empowering the everyday dad and showing some research into the differences between mums and dads with biopsychosocial evidence.

There is a real argument to be made on the role of the father, and the importance of fulfilling that role in a child’s life to support their development. There is also recognition that differences in culture and gender roles can be factored in, they can also be adapted. The book dismantles the war on sexes and advocates for *parenting* as a union between parents and the roles they play.

This book is arguing for the present father, the involved parent, the playful dad, the laid back dad, the recognition of Dads, the enhanced parental leave Dad, the cares for the mother Dad. This book is arguing for replacing absentee dads with great dads and breaking down the patriarchy in business and law by moving us towards a culture where both parents have equal stakes in the game and can be supported to step up and sacrifice for their kids.

I enjoyed the book, it is accessible at an entry level and doesn’t need previous knowledge of psychology to understand, although does help if you want to read the book quickly.

My only gripe is the focus on American Policy, which is translatable and relevant at a distance for a non-US reader.

[Ja · Rating 4 out of 5]

When it comes to parenthood, there's already a lot of research on moms and motherhood. And that's a good thing, seeing as how their bodies are literally growing a baby and they go through so many physical changes that it's hard to just ignore that aspect of reproduction. But in turns, there's actually a dearth of research and, ultimately, support for fathers. Dads go through a lot of changes as well, and it's important to recognize these differences.

When becoming a father, dads gain weight (think dad bod), their testosterone levels lower, and go through their fair share of psychological stress. Dads can also get postpartum depression (or paternal postpartum depression), which is also an important sign to look out for. Saxbe explores other aspects of changes that occur during fatherhood, as well as some of the cultural progress that has been made in regards to parenthood as well.

What I thought I would be reading about but didn't get much of was actual brain chemistry and data. For a book called Dad Brain, I thought there would be more brain focused information.

A great book to read if you're looking for a little more information and research about dads, and parenthood in general.

[Ian Jobe · Rating 4 out of 5]

Much has been written about everything that affects women when they have a child (physically, hormonally, emotionally), but do any changes happen to men? Are they the same as they were before becoming fathers?

This book explores that idea and presents a lot of evidence that becoming a father can change men in many similar ways.
For example, fathers see their testosterone get lower when they become fathers. The drop in testosterone corresponds with a rise in chemicals that make fathers more affectionate. In one study, men with the largest testicles were rated by their partners as being less hands-on caregivers (how could I make this up?)

The book also goes into how Dad's can affect their kids and partner, both negatively and positively. When a child has an obese father and a non obese mother, the child is 15x more likely to be obese than in the reverse situation. Also, infants whose dads are equally involved in parenting were found to sleep better, have less wake ups, be less fussy, etc.

This book had a million interesting studies that I enjoyed.

The only reason it's getting 4 stars instead of 5 was because the beginning was a bit slow and the last few chapters had information that I'd read in other books (e.g., importance of raising high quality men).

I recommend this book to all. Men and women alike as it's important to appreciate the role a good father can play.

[Patrick Little · Rating 5 out of 5]

What idea from this book do you expect to still remember in a year?
Fathers share an equal if not more important role in raising a child. Not only does my presence influence the mother of my child but also plays an important role in the continued development of the child.


Which single scene, chapter, or argument carries the most weight?
Chapter 12: fathering beyond biology
Coming from a blended family where I had to navigate building and maintaining a relationship with both my biological father along with my step father this section helped reinforce it does not matter how dynamics might be, it is still critical for a father to be present and aware of the effects their actions have.


What other book or media does this book remind you of?
In sections, the book reinforced the general need for positive masculinity in media and life in general. Working in advertising, I understand how media has ability to reinforces positive along with negative stereotypes and how it is left up to the individual to be aware of the effects they may have. Instead we need to be conscious and work together to promote and talk more openly about the positive examples in order to both destigmatize what it takes to be a positive male in society and how it has to be an active choice which takes continual work in order to accomplish it.

[Josh Owens · Rating 5 out of 5]

A wonderfully insightful and entertaining book. Whether you are a father, about to be a father, considering becoming a father, or just someone who has had a father, this book provides research about the various ways fathers experience parenthood emotionally and mentally. While steeped in empirical research it is presented in ways that are accessible to all, often accompanied by the author's own life experiences or readily familiar popular culture references. It raises important questions around how men lack support in some key areas, and why reimagining the role of fathers socially and politically can go far in improving the life of children and our society as a whole. Highly recommend.

[Brett Shand · Rating 4 out of 5]

Cool book, I learned a lot about how being a dad can change your brain, body, and place in society. A ton of great science and research to back it all up. Awesome book for any dad who wants a unique science based perspective. Also learned about papadag - which is a largely socially acceptable practice in the Netherlands where dads take one day off per week (4 day work week) to spend with their children. American society does a good job at encouraging women to be amazing and involved mothers, but discourages men from doing the same. I’m not afraid to be a loving and involved father, but other places in the world do it much better than us. Everyone benefits from good dads.

[Bret Branson · Rating 3 out of 5]

As a dad I have read many books on fatherhood but mostly within a Christian lense, so I wanted to see what a secular book might say about fatherhood.

I appreciated the research that went into this book even if some of it seemed superfluous (especially in the early chapters). When it gets to the point - thoughts on the biology, hormones, and overall neuroscience of fathers - it is fascinating.

Still, I found it strange that in this book about fathers, it feels like the attitude is that fatherhood is a bonus trait we have evolved into, instead of something essential to the health of children and society as a whole.

I still appreciated the read and the clear stance that fatherhood is important. Even if that stance is more flimsy without a real moral framework to lean on.

[Levi · Rating 5 out of 5]

When I became a father I knew my brain had changed, and this book explains exactly how and why that is the case. Parenthood is ever changing through time and culture, and fathers are (in most cases) spending more time with their children than ever before.

I would recommend any new father give this book a go, it provides an understanding you may perhaps not get the opportunity to learn otherwise.

[Terry Dykstra · Rating 4 out of 5]

The research behind what happens to dad’s brains (of course) when men become fathers and the social, emotional results. I was interested as a stay at home dad but this book makes a compelling case for the importance of father and fatherhood for the good of their kids, partners, community and beyond.