How We Grow Up: Understanding Adolescence

by Matt Richtel

Building off his award-winning New York Times series on the contemporary teen mental-health crisis, the Pulitzer Prize–winning science reporter delivers a groundbreaking investigation into adolescence, the pivotal life stage undergoing profound—and often confounding—transformation.

The transition from childhood to adulthood is a natural, evolution-honed cycle that now faces radical change and challenge. The adolescent brain, sculpted for this transition over eons of evolution, confronts a modern world that creates so much social pressure as to regularly exceed the capacities of the evolving mind. The problem comes as a bombardment of screen-based information pelts the brain just as adolescence is undergoing a second key puberty is hitting earlier. The result is a neurological mismatch between an ultra-potent environment and a still-maturing brain that can lead to anxiety, depression, and other mental health challenges. It is a crisis that is part of modern life but can only be truly grasped through a broad, grounded lens of the biology of adolescence itself. Through this lens, Richtel shows us how adolescents can understand themselves, and parents and educators can better help.

For decades, this transition to adulthood has been defined by hormonal shifts that trigger the onset of puberty. But Richtel takes us where science now understands so much of the action the brain. A growing body of research that looks for the first time into budding adult neurobiology explains with untold clarity the emergence of the “social brain,” a craving for peer connection, and how the behaviors that follow pave the way for economic and social survival. This period necessarily involves testing—as the adolescent brain is programmed from birth to take risks and explore themselves and their environment—so that they may be able to thrive as they leave the insulated care of childhood.

Richtel, diving deeply into new research and gripping personal stories, offers accessible, scientifically grounded answers to the most pressing questions about generational change. What explains adolescent behaviors, risk-taking, reward-seeking, and the ongoing mental health crisis? How does adolescence shape the future of the species? What is the nature of adolescence itself?

Genres: Nonfiction, Psychology, Parenting, Self Help, Health

336 pages, Hardcover

Published July 8, 2025

About the author

Matt Richtel is a best-selling author and Pulitzer Prize-winning reporter for The New York Times based in San Francisco.
He co-created and formerly wrote the syndicated comic Rudy Park under the pen name Theron Heir. Since 2012, the strip is now written by its longtime illustrator Darrin Bell.

Reviews

[CatReader · Rating 3 out of 5]

Matt Richtel is an American journalist and author of both fiction and nonfiction; I previously read his 2019 book nonfiction science book An Elegant Defense: The Extraordinary New Science of the Immune System: A Tale in Four Lives, which I felt was too simplistic. His latest book; 2025's How We Grow Up, focuses on modern adolescence in Gen Z (those born late '90s to early '10s), whom Richtel aptly dubs "generation rumination."

Richtel posits that adolescence today begins earlier, driven in part by earlier puberty and the changes in brain chemistry that brings, and lasts longer, often extending well into one's 20s. This is contrast to earlier generations when adolescence wasn't really a prolonged or conceptualized life state as circumstances often forced children to mature and assume adult roles very rapidly. I think often of my Polish grandmother who quit school around age 8 to work on her family's farm, was 12 when Hitler invaded Poland in 1939, was taken from her family and conscripted into labor for a German family in the ensuing years, was a war bride and teenage mother living in a foreign country by the time she was 19. Indeed, the concept of adolescence/teen years (which Richtel differentiates but I largely view as the same) didn't really emerge until after World War II in the West, when young people had luxuries like stable and peaceful societies, social structures like high schools and colleges, well-developed infrastructure like easy access to food and transportation, and reproductive choice.

How We Grow Up is strongest when it highlights these contrasts, but unfortunately much of the writing meanders into tangents. Richtel relies heavily on (in my opinion) overwrought and overly dramatic portraits of young people who struggle with stereotypical early 21st century issues like sexual and gender identity, social media influence, and mental health issues. These insights aren't particularly novel or distinctive, especially compared to stronger recent works in this area.

Ultimately, How We Grow Up wasn't a terrible read, but it doesn't stand out to me in an already crowded niche.

Further reading: travails of Gen Z
Bad Therapy: Why the Kids Aren't Growing Up by Abigail Shrier
Pixel Flesh: How Toxic Beauty Culture Harms Women by Ellen Atlanta
What Made Maddy Run: The Secret Struggles and Tragic Death of an All-American Teen by Kate Fagan (the titular subject is technically a late Millennial, but still relevant)
Generations: The Real Differences Between Gen Z, Millennials, Gen X, Boomers, and Silents―and What They Mean for America's Future by Jean Twenge

My statistics:
Book for 2025
Book cumulatively

[Barbara McVeigh · Rating 4 out of 5]

3.5 stars

Clear language and bite-sized chapters make this book on adolescent psychology a breeze to read. But there were often times when I got to the end of a chapter, I wished that Richtel would’ve have gone a little more deeper with his research and analysis on that chapter’s topic.

Here’s my two takeaways about modern adolescents a la Richter:
-adolescence is starting earlier because of poor diet, i.e., junk food —the brains of younger adolescents are not as prepared for the coming changes, experiences and information
-smartphones are used to access so much information that a teen’s still developing but curious brain is easily and often overloaded, causing anxiety

And two takeaways about adolescence, in general:
-this period of time is about creativity, being an iconoclast, and changing our world. Adolescents see how things could be and break away from the old way of doing things
-corporations are more than willing to exploit and co-opt the above-listed impulses

[Laura Gardner · Rating 4 out of 5]

Lots in here about teenage brain development…maybe more than I wanted, lol. Love the anecdotal stories. I read this book after hearing the author on NPR. I was most interested in learning about the youth mental health crisis as it relates to technology (perfect design for teens, who are Social in nature and wired to explore) and changes in puberty (happening earlier because of better nutrition and lasting longer).

[Carrie · Rating 5 out of 5]

Ooh, there were things I wasn’t expecting.

Biggest takeaways:

- girls are getting their periods sooner, especially if they are overweight.

- brain connections become fewer but stronger in adolescence so best get your pre-adolescent to start learning things you want them to be good at later.

- kids these days are spending more time alone with media. On one hand, it’s leading to a decline in things like drug use and sex but on the other hand, they feel terrible and do more self harm. Better to limit the devices.

- age 14 is when kids take the most risks.

- teens don’t listen to their mothers as much as they listen to strangers. An experiment proved it! This is because the kids need to learn to make it without their parents at some point. They need to have more input than their parents in order to adapt to a changing world. They all cast off in their own ways but it is natural.

[Jung]

In "How We Grow Up" by Matt Richtel, adolescence is reframed not as a problem to fix but as an essential stage of human evolution. Far from simply being lazy, rude, or obsessed with their phones, teenagers are shown to be carrying out vital biological and cultural functions. Richtel argues that what often looks like rebellion or dysfunction is in fact a deep-rooted survival mechanism. This book combines neuroscience, history, and vivid stories to illustrate how the teenage years are designed to challenge traditions, test boundaries, and drive society forward.

Adolescence has always been difficult, but modern teenagers appear to be struggling more intensely than previous generations. Depression, anxiety, and self-harm are on the rise, while risky behaviors once synonymous with youth - drinking, smoking, reckless sex - have declined. Instead of acting outwardly, today’s teenagers are turning inward, wrestling with identity, meaning, and purpose. Richtel suggests that this shift reflects both the unprecedented pressures of the digital age and the brain’s natural drive to innovate. For teens, rebellion isn’t a flaw but an evolutionary feature, and recognizing this truth allows parents and educators to approach them with compassion instead of judgment.

Stories from history illustrate that adolescent disruption is not new. Francis Billington, a fourteen-year-old aboard the Mayflower, nearly blew up the ship with a misfired musket and later believed he discovered a new ocean, only to have found a pond. Generations later, Thomas, also fourteen, threw glitter during a marriage equality protest, continuing the tradition of young people redefining boundaries. These tales, separated by centuries, demonstrate that teens have always acted as explorers - sometimes of physical frontiers, sometimes of social ones. Their risk-taking has always been society’s way of ensuring fresh perspectives.

Yet the risks teenagers face today look different. Many turn inward when overwhelmed, as seen in the story of Henry, who struggled with an eating disorder during the pandemic. Seeking control in a chaotic world, he restricted his food intake to dangerous levels. His crisis highlights how modern teens often grapple with internal pressures rather than external dangers. At the same time, this inward turn can lead to profound discovery. Anna, for instance, used adolescence to reflect deeply on identity, ultimately finding the courage to transition and live authentically as Thomas, the same teen who protested with glitter. In both pain and triumph, these stories reveal that the adolescent drive for exploration often unfolds on the psychological level today rather than in physical frontiers.

Scientific research backs up this transformation. Adolescence is not just a cultural invention but a biological stage of immense brain remodeling. During this period, unused neural connections are pruned while heavily used ones are reinforced, increasing efficiency. This process fuels risk-taking, novelty-seeking, and identity formation. The brain’s reward systems mature earlier than its regulatory systems, meaning teens are neurologically primed to take chances before they develop strong brakes. Far from being evidence of immaturity, this setup ensures that each generation produces individuals bold enough to break from established ways. Nobel Prize winner Jim Allison, for example, was once a defiant teenager who challenged teachers and caused small explosions in labs. His adolescent stubbornness later powered scientific breakthroughs.

Another striking discovery is that teenage brains actually rewire to prioritize the voices of strangers over their parents. Brain scans confirm that reward centers light up more for unfamiliar voices than for those of mothers, nudging adolescents toward new social connections. This neurological mechanism ensures young people seek independence and establish networks beyond their families. While it can cause heartache for parents, it is crucial for the survival of societies that need each new generation to form fresh bonds and question old rules.

Modern conditions, however, amplify the challenges inherent in this rewiring. Puberty is beginning earlier than ever, sometimes as young as six in girls, colliding with brains that are still ill-prepared for complex decision-making. At the same time, social media floods teenagers with unprecedented amounts of information and social comparison. Richtel describes this as 'Generation Rumination,' where the mismatch between ancient brain design and modern technology creates overwhelming stress. The digital world acts less like a weapon and more like an amplifier. For teens already struggling with self-esteem or rejection, platforms magnify despair. For those with stronger support systems, social media can foster creativity and belonging.

The concept of 'differential susceptibility' captures this duality. Courtney’s story demonstrates the danger. Receiving her first iPad during early puberty, she sought validation online and adopted an older persona. While this gave her the attention she craved, it also exposed her to predatory adults, leaving her frightened and conflicted. For vulnerable adolescents, the digital world can become a trap rather than a refuge. At the same time, healthier outlets are being displaced - sleep, exercise, and real-world connection have all declined as screen time increases, compounding the risk.

Despite these struggles, adolescence is not a broken system. It is a paradoxical but necessary phase, one where creativity and destruction coexist. Some teens, like Lindsey, fall into perilous paths of drugs and crime, ending up in prison before adulthood. Yet even in such extreme cases, resilience can emerge. After serving a long sentence, Lindsey rebuilt her life with legitimate work, demonstrating that the developmental drive for reinvention can persist well beyond adolescence. Others, like Thomas, transform self-discovery into activism, proving that the energy of youth can expand society’s definitions of equality and justice.

Richtel underscores that adolescence as we know it is relatively new in human history. For centuries, children transitioned quickly into adult work, leaving no room for extended self-discovery. The modern teenage experience - filled with experimentation, introspection, and identity crises - emerged only in the last few hundred years, shaped by literature, psychology, and cultural shifts. Yet what remains constant is biology. The brain’s massive reorganization during puberty is nature’s way of fostering diversity, creativity, and innovation. Adolescence may be chaotic, but it is humanity’s method of evolution.

The tragedy is that for some, the combination of impulsivity, despair, and easy access to lethal means leads to irreversible outcomes. Henry’s suicide, despite his apparent progress toward recovery, demonstrates the fragility of this stage. Such moments are stark reminders of why understanding and supporting adolescents is vital. Teenagers are not miniature adults or broken children; they are evolutionary explorers caught between competing drives, navigating a storm that is both necessary and perilous.

In conclusion, "How We Grow Up" by Matt Richtel redefines adolescence as a crucial, if turbulent, phase of human development. Teenage rebellion, once dismissed as immaturity, is revealed as biology’s way of pushing each generation to innovate and expand human potential. Today’s teens, navigating earlier puberty, relentless technology, and inward journeys of identity, face unprecedented challenges. But they also hold immense potential to shape the future. Recognizing adolescence not as pathology but as purposeful evolution invites adults to guide with patience, empathy, and trust. Supporting teenagers means giving them the space to explore while providing the boundaries to keep them safe. In doing so, we acknowledge their role as society’s innovators and honor the difficult but vital work of growing up.

[Joan Fung-Tomc · Rating 3 out of 5]

Perhaps the most informative knowledge I gained from this book was about how the brain changes during adolescence. The brain is made up of neurons (brain cells; gray matter) and synapses (communication system between neurons; part of the white matter). During the 1st year of life, there's an explosion of synapses. At adolescence (now starting around 10 years of age), there's a pruning of synapses (about 1.5%/yr).

Synaptic connections reply on axons (microscopic tubes on neurons that help to transmit information from neuron to neuron). During adolescence, the axons become myelinated (ie, covered with a white, thick layer) and the resulting insulated axon allows information to move more quickly. So, information travels more efficiently across myelinated vs. nonmyelinated axons....resulting in a specialization or more defined characteristics, talents, behaviors of an individual.

In other words, in childhood, when the neurons are not myelinated and the network is less differentiated, it is receptive to a broad base of learning. This is the period when the brain learns to think, process information and curiosity, analyze before it becomes more differentiated. Therefore, early childhood years are essential times to read, write, and learn.

[Margaret Marie · Rating 3 out of 5]

I was *stoked* about this book. I mean, I’ve got a 9-year-old. I need to cram.

Overall, I enjoyed the short chapters, and I needed this reframing of adolescence. But I closed the book feeling a bit disappointed.

Some info was dropped without fleshing out its implications. e.g., Puberty hormones get cranked out at night! But a lot of kids don’t sleep enough, right? But puberty is starting earlier? Huh?

Richtel’s chapter about psychotropic meds and specific diagnoses would have benefited from review by a medical professional. If he knows there’s a difference between antipsychotics and antidepressants, he did not demonstrate it. And the alarm over the SSRI black box warning is just… sigh. Not to mention his NP panic when there are plenty of MDs out there prescribing immediate release Adderall with a benzo on the side. His point about nailing a diagnosis correctly in the first place though? 🎯

I guess I was hoping for some more actionable information. But maybe that’s Jonathan Haidt’s schtick.

[Bobby Asher · Rating 5 out of 5]

I've been teaching adolescents for over three decades. I’ve coached boys and girls for twenty-five years, and I have three twenty-something daughters. As a high-school neuroscience teacher and part-time administrator, I read every book about parenting and/or the brain I can. None is better, more engaging, more informative or more grounded in neurobiology than Matt Richtel’s How We Grow Up. Like only the best writers, Richtel combines extraordinary storytelling (and the stories he shares could not be more compelling) with a remarkable ability to make some high-level science not only understandable but also downright fun to read. I recommend this book especially to parents and educators (as well as their students), but also to anyone who’s curious about the brain. It is that rare science book that reads like a page turner! Honestly, I cannot say enough.

[Elizabeth · Rating 5 out of 5]

I read this after reading a very positive review in the New Yorker, particularly about Richtel's more progressive attitudes toward the connection between technology use and mental health. While I don't think that Richtel is quite as pro-technology as the review seemed to imply, what he does offer in this book is a holistic look at the challenges that face adolescents today, including those that emanate from technology use. The holism was much appreciated, as was the clarity with which he explained complicated scientific studies and the care with which he paired them with in-depth profiles of contemporary adolescents. As someone who engages late-stage adolescents through my work, I'm very glad to have read this for the perspective it offers. And I'd recommend it to anyone who seeks to meaningfully interact with, mentor, or parent adolescents today.

[Judith · Rating 3 out of 5]

I liked having the six "case" studies and commend the one who allowed the use of their dead name in this book. Thinking back on my own adolescence I am glad I didn't have social media to contend with and the prevalent use of drugs which has become pretty well normalized. Richter uses conversations with child/adolescent psychologists as well as medical/scientific papers as sources, but I am surprised that no bibliography is given; I think there would be some bibliography, although he does give professional sources, but simply the title (e.t. Pediatrics) and the year but not author, volume, page numbers. I wish at the end of reading this that I had more hope that as a society we might make things better (? easier? more supportive of adolescents?). What did astonish me is how long adolescence goes on and how early it starts (both mentally and physically).

[Margot MacKay · Rating 3 out of 5]

I found this book less digestible than ones by Damour and Grant, two of my preferred psychology writers. Richtel focuses more on the biology occurring during adolesence, and formats his book with profiles of teens, tracking their journeys and struggles, which include brushes with crime, LGBTQ+ challenges, and suicidal ideation. While I found this a pretty interesting read, there were definitely portions where I was skimming -- and though I've added it to my "parenting-teaching" bookshelf, I'll still lead with my tried-and-true favorites from that list.

[Samcwright · Rating 2 out of 5]

Honestly, I can’t remember how I found this book or why I read it. I’m 90% sure the science will change by the time. My children are old enough for it to apply to them. I didn’t find it particularly insightful and not sure it adds much to the discussion around what’s happening with kids as they grow up especially in today’s modern environment.

Key themes:
• Evolutionary purpose of adolescence
• Brain–environment mismatch
• Digital stress and mental health
• Empathy and connection as guidance

Those sound way more interesting than the book actually was.

[Nancy · Rating 3 out of 5]

A bit dense at times with the science/brain information. I was expecting something else from the book. (More anecdotes, and more for a layman like me.) Many parts were very informative but I had to skim through some of the sections that were not how I thought the book was going read.
3.5 stars, but rounded down for the disappointment factor.

[Elizabeth Ireland · Rating 5 out of 5]

This was a page-turner even though it’s nonfiction, which can de dense. It so clearly walked through the research about adolescent brain development and connected it to stories of young people. It gave me such a better appreciation of what this generation is facing and how to support my children through this pivotal phase of growth and development.

[June Freifelder]

Finally finished this one after running out of time on the audio and waiting for the FLP to get it together. I really enjoyed the vignette pieces of this book and found some of the science to be interesting too. While nothing shocked me, it generally felt more well-rounded than the Anxious Generation.

[Josh Lott · Rating 5 out of 5]

I was very surprised by this book. It did feel like it went off in tangents here and there, but it all tied together in the end, offering offering an encouraging perspective on how to care well for the next generation.

[Jessica · Rating 4 out of 5]

My kids are 5 & 7, but I enjoyed reading the science behind adolescence coupled with the practical advice and profiles of adolescent stories. I hope this read will help prepare me for the next chapter with my kids!

[Laraine · Rating 5 out of 5]

This is a very scientific researched book about what affects Adolescence in their body and through their environment. If your looking for data on whether or not to allow your student screen time - this will help you determine it.

[Ta0paipai · Rating 2 out of 5]

The book’s title implies it’s about adolescence and the changes that take place during that period. However, the book is more focused on specific anecdotes that push an agenda. It started off somewhat wide reaching but spiraled out of control by the end.

[Kelly snailz Martin · Rating 3 out of 5]

Not my favorite. I didn’t love the writing style and felt like the book was missing direct connection to the literature (ie, “the science doesn’t say this” - what does it say? What are the citations?). I wanted more than just quotes for conversations

[Vanessa · Rating 4 out of 5]

The author does a terrific job of building a narrative that propels the reader through the data. Really interesting content for anyone raising kids, or who cares about supporting young people & the future leaders of our world.

[Megan Roth · Rating 4 out of 5]

Richtel writes with so much heart, especially for a nonfiction book. Really enjoyed the personal stories, his voice, and analogies.❤️

4 stars instead of 5 because there were some redundancies in the beginning.

[William · Rating 4 out of 5]

Great reporting on a surprisingly complex topic.

[Sherry · Rating 5 out of 5]

Written in an engaging style and well-researched, this book investigates the issues of adolescence without posing pat answers or inciting panic over social media

[Barbra · Rating 3 out of 5]

This is more origin, data, and case study based. I was hoping for more tools and supports than what was provided. Still an important read.

[Wesley · Rating 2 out of 5]

bad writing and bad science delivered by an old white man. gave it back 1 star for including trans people.

[Tracey Eyster]

DNF as his point was made. Interesting information.

[Teresa · Rating 2 out of 5]

Not at all what I was expecting. A strange mashup of history, child development, neuroscience, biography. It felt like each chapter was a different type of book, with no clear order.

[Art · Rating 4 out of 5]

This book is fascinating. It contains many insights, at least for me. Some of the subject matter is a bit difficult to read because it's sad (eg, suicide), but it certainly held my interest. I also appreciate the way the author explained matters very well.

Since I received an evaluation version, the mistakes I see are more understandable than if it was a finished product.

I am grateful to have received this book through a Goodreads giveaway. Peace be with you.