Is the Falling Age of Puberty Adding to the Teen Mental Health Crisis?

Family therapist David Kalergis remembers one 8-year-old girl in particular. She plopped down on the cushy chair in his Mount Pleasant, SC, office, unsure of what to say. Her parents had already told Kalergis that in recent months the girl smelled differently, pungent. By lunchtime she already needed a bath. Her parents felt “in over their heads” because they hadn’t expected that their little girl would already need deodorant. What’s more, they weren’t sure how to address the birds and the bees with a child so young she didn’t even know what sex was.

When Kalergis brought the issue up to the little girl, she was at first embarrassed, but then she opened up. She could finally discuss what was happening – the body odor and budding breasts. She needed deodorant and a bra, and her parents would just have to accept that.

“It’s the parents who are in denial that present the biggest issue,” says Kalergis. “Those who refuse to believe that their child could possibly be developing at an age that seems much younger than when they went through puberty.”

The kids look different, and that makes them a target. “When they go to a pool party and have to change into their swimsuits, it’s embarrassing because their friends still look like little kids and they’ve started developing into adults,” he says.

That experience can be profoundly isolating for children – and silencing. “It’s usually the parents that come to me first,” says Kalergis, founder and owner of Lowcountry Family and Children in Mount Pleasant. “But once I broach the subject, the kids open up.”

No Clear Cause

What Kalergis is noticing in his practice is occurring on a global scale. A growing body of research shows that kids throughout the world are going through puberty at a younger age than ever before. An April 2020 study published in JAMA Pediatrics looked at data over the past 4 decades and found that the age of puberty onset in girls decreased by almost 3 months per decade. The numbers are similar in boys, though not as dramatic.

While researchers agree that earlier puberty is becoming more common, they’re not completely sure what’s driving the change, says pediatrician Kathryn Lowe, MD, author of You-ology: A Puberty Guide for Every Body. She says that there’s some research showing the impacts are caused by chemicals in the environment impacting the endocrine system. Stress has been shown to be another cause, and other research has shown that a growing obesity epidemic in kids is contributing to the change. Kids who weigh more tend to develop younger. “We’re not completely sure, but we think it could be multifactorial, meaning that different things are causing it in different kids,” she says.

Puberty research has long been racially skewed (the majority of it has been done in white males and females), but recent research has exposed racial disparities in the age of puberty. Girls, says Lowe, typically start puberty between the ages of 8 and 13, though that age can be lower in Black and Hispanic girls. Breasts begin budding, hair may appear on the pubic area, and they may experience a growth spurt. Boys tend to start a little later, between the ages of 9 and 14, though Black and Hispanic boys also tend to start younger. Early male puberty includes growth of the scrotum and testes as well as hair around the penis and a growth spurt. Researchers aren’t sure what causes the racial differences, but they think that stress may be partly to blame.

Early puberty, known as “precocious puberty,” happens when these changes occur before age 8 or 9. Though uncommon (occurring in about 1% of kids), early puberty happens when the pituitary gland, a grape-sized gland at the base of the brain, turns on too early, sending signals to the rest of the body to start developing. Hypothyroidism, or an underactive thyroid gland, is another cause. And in extremely rare cases, precocious puberty is caused by a tumor in the adrenal gland.

Physical and Mental Health Consequences

Some research in women has shown that girls who go through puberty on the younger end of the spectrum are at a greater risk for breast and uterine cancers later in life. And a wide body of research points to spikes in depression and anxiety. “The brain is changing a lot during this time and that, accompanied by hormonal spikes, might have an impact on mood disorders,” says Lindsay Hoyt, PhD, who runs the Youth Development, Diversity and Disparities (3D) Lab at Fordham University in New York City.

The falling age of puberty is coinciding with a time when teens are already in crisis. A recent study from JAMA Network found a nearly 30% increase in teen depression and anxiety from 2016 to 2020. Hoyt notes that the changes in puberty are incremental and have been happening for decades, long before recent spikes in depression and anxiety. The current teen mental health crisis has no shortage of other causes. For starters, today’s kids feel more weight on their shoulders to succeed. A 2016 survey of teens entering college found that 34% of them felt “overwhelmed” compared to 18% in 1985. Their world feels unsettled; everything from lockdowns and active shooters at school to masking and the pandemic have upended their lives in recent years. And social media doesn’t help either. A review of 36 studies in JAMA Pediatrics found that 23% of kids said they were the victims of cyberbullying. Teens who start developing younger may simply be running headlong into grown-up anxiety and depression earlier than they can handle.

Hormones are part of the picture. Researchers aren’t entirely sure why early puberty might be causing mood disorders in kids. But some data has shown that the developing brain in younger children might be more sensitive to spikes in estrogen and testosterone. Still, the lion’s share of poor mental health outcomes result from social changes. Hoyt’s research has shown that unhealthy body ideals may make young girls feel like they don’t fit the image that they’re supposed to anymore – their hips, breasts, and thighs cause them to stand out in a bad way, she says. “They don’t fit that idolized body type and those changes in weight distribution aren’t happening to the other girls their age,” she says.

Additionally, girls who reach puberty earlier are often the target of sexual harassment. They may look older than they are, which means they begin getting sexual attention before they can interpret what it means. Another study, published in the Journal of Adolescent Health, found that girls who are sexually abused are more likely to reach puberty earlier. The most likely culprit is the stress brought on by the assault and abuse.

We know a lot less about how early puberty impacts boys because boys don’t get their first period, or any other particular point that marks puberty’s official beginning. And most puberty studies are retrospective, which means they rely on the memories of the people studied. Girls often remember their first period; boys have nothing specific to point to. The most noticeable aspects of male puberty, like growth spurts and facial hair, aren’t a good marker because they happen at the end of puberty. Still, research has shown that early puberty in boys does cause depression and anxiety as well as body dissatisfaction. Boys are more likely than girls to act out with aggression, delinquency, and overall risk-taking behaviors.

“During adolescence, both boys and girls just want to be like everyone else, but if you’re off time and going through something earlier, it can cause stress,” Hoyt says.

Kalergis is doing everything he can to reconnect parents and kids and help them better understand one another, even when things feel strange and uncharted. “These kids already feel like outliers from their friends, and they don’t need to feel isolated from their parents too,” he says.