Over the past year, a friend’s daughter – let’s call her Lily – has repeatedly called herself ugly.

When Lily is supposed to be brushing her teeth, she looks in the mirror with a frown on her face, eyes scanning her features with disappointment.

Lily has wavy dark-brown hair; she wants straight blonde hair.

One morning Lily put pink marker all over her mouth. The day before, a child at school had called her ugly, and she thought the “lipstick” would make her look prettier.

Lily is 4. And she is beautiful.

How has the world warped this child’s view of herself? Why does Lily even need to care about looking beautiful at 4? Is she worried about getting a date for the class field trip?

More attention is finally being paid toward the harmful effects of social media on teens’ body image and mental health. However, a study my lab conducted suggests that we are missing an important piece of the puzzle. Specifically, we discovered that among girls, a preoccupation with appearance starts as young as age 3.

In our study, we interviewed 170 children ages 3 to 5 to examine when kids start to value being beautiful. Across all of the measures that we assessed, girls on average greatly valued their appearances. Girls said that to be a girl they needed to be pretty, and looking pretty was important.

When asked to select from an array of outfits and occupations, the girls in our study tended to select many fancy outfits and appearance-related occupations, like being a model or makeup artist. They showed good memory for pictures of fashionable clothing when these pictures were later hidden from view.

When explaining why they liked a pop culture character, girls often said things like, “I like all the princesses because they are pretty.” In a previous study, young girls also tended to purchase many toys that focused on appearance (e.g., a vanity set) with play money.

Across both studies, not only did girls tend to care highly about appearances, but they also did so more than boys.

Girls were about five times more likely than boys to say they liked a character due to what I refer to as “appearance reasons”.

Boys more often cited “action reasons,” such as liking Spider-Man “because he jumps high, climbs and shoots webs”.

Our study concluded that gender differences related to how much emphasis we place on beauty likely start in preschool.

While girls around the world have long been taught that beauty is of utmost importance, conversations with other gender development experts point to the early 2000s as a pivotal period when a new “girlie-girl” culture emerged.

One driver of this culture was the launch of the Disney Princess franchise in 2000, which continues to enamour young girls. My two young daughters have probably drawn upwards of a thousand pictures of Moana over the past two years.

Although Disney movies have evolved and now try to include more agentic heroines, the take-home message received by children still centred on beauty.

By adolescence, children are already primed to be preoccupied with how they look – a vulnerability that social media, often a very visual platform, taps into and exploits.

Decades of research have shown that tying self-worth to looks and having a distorted body image are linked to a whole host of negative outcomes, which can include poorer physical health (e.g., eating disorders, substance abuse) and mental health (e.g., depression). An unhealthy focus on appearance can also detract from a focus on school, interfere with academic performance and limit the career aspirations of young women.

If we know that emphasising physical appearance sets girls up for unhappiness – or worse – we must rethink our words and actions that instil this value, and we must begin before adolescence and social media use.

The preschool and kindergarten years are especially critical, as it’s during this time that children typically begin to strongly identify with a gender – whether the one they were assigned at birth or the one they know themselves to be – and they are hungry to learn what that gender means.

Children form gender stereotypes based on the information that is available to them and often doggedly follow these stereotypes. Because children are learning that girls are defined by how they look and boys by what they do, we must change the information they receive.

We can do this in a variety of ways. One is to (re)examine the images and toys our children encounter on a daily basis. Those beloved princesses and mermaid dolls with absurd body proportions can create internal standards that are impossible to attain.

Although adults understand the metaphor in making a superhero larger than life, children, who are extremely visual and swayed by how objects and people look, take these images at face value. We need to buy and create toys that feature diverse body shapes and sizes, varied and accurate facial features, different hair textures and a spectrum of skin colours.

There are some bright spots already out there. Our family loves the three Madrigal sisters from the movie Encanto. Mirabel, the main protagonist, has glasses and curly hair. Her oldest sister Luisa is renowned not for her beauty, but for her physical strength. Isabella, the middle sister, has darker skin and realistic body proportions that my children not only see but also feel when handling their dolls. The village values all three of them for their helpfulness, and their primary goals do not centre around attracting a prince. Barbie is also making more diverse dolls, but those more representative toys are still the minority.

There are also toys and games that encourage girls to solve problems, build structures and robots and use their creativity, but because our culture is still so influenced by gender stereotypes, young girls are often not exposed to them. We need to not only add positive and diverse images and toys, but move away from featuring and selling the harmful ones that currently dominate the market.

Until corporations do better, it’s up to us to do what we can. If you find yourself reaching for an “appearance toy” for a girl in your life, look for toys that encourage a wider variety of activities. Believe me, harmful images and toys will seep into your household, often through gifts from friends and family members, so parents and teachers need to take an active stance. Don’t feel guilty saying no to a toy that promotes an unhealthy approach to appearance.

We can also change how we talk to the children in our lives. Instead of constantly commenting on a child’s appearance – “You look so pretty!” or “That’s a beautiful dress!” – try focusing on other admirable attributes, especially when you’re speaking to girls.

On a broader level, let’s expand the idea of what a girl or a boy can be. By having more examples of the different ways that kids can be their gender (whether by being more or less traditionally feminine, masculine or something in between), everybody wins.

Of course, it’s important to instill a sense of pride in one’s appearance. But this is possible without focusing on traditionally esteemed – and frequently policed – characteristics. It can be even more complicated for children of colour or children from low-income backgrounds, where looking “good” can be unfairly and dangerously tied to respectability.

In these contexts, parents are often actively fighting to keep their kids from internalising insidious white beauty standards, in addition to challenging gender stereotypes.

And although appearance is typically emphasised more among girls, boys also face unrealistic standards regarding muscles and strength. One study found that 49% of boys ages 8-12 were unhappy with their appearance and another found that boys as young as 6 showed preferences for thinner and more muscular bodies.

Many of us relate to feeling dissatisfied with the way we look and have experienced negative outcomes due to our fixation on it. As a 12-year-old, I was obsessed with the weight I gained during puberty. Though doing varsity volleyball and track and field made me fit and strong when I was 15, I was unhappy with my body, and experienced depression and suicidal ideation.

I was not alone. I knew many other girls who were dealing with similar feelings. When I later attended Stanford, I was surrounded by incredible, high-achieving women, some who were world-class athletes, but who also struggled with their body image and disordered eating.

Seeing so many others who also suffered made me realise that these appearance- and health-related matters were bigger than just me.

Ultimately, I was motivated to study gender development as a career, which I’ve been doing for 17 years, in the hopes of addressing this complex and alarming societal issue.

I am anxious about what will happen when my two young daughters become teens, in a society where sexism and patriarchy still run rampant.

My husband and I have even contemplated leaving Los Angeles, arguably one of the most image-obsessed cities in the world.

Whenever we drive down Santa Monica Boulevard, billboards and advertisements expose my daughters to the supposed wonders of plastic surgery, implants and freezing off fat.

When we traipse down Montana Avenue, a swanky shopping area, we pass dozens of eyelash salons, hair salons, nail salons, waxing salons, sugaring salons and skincare shops squeezed in tightly next to each other along the street.

I know that these messages would still reach them no matter where we moved. This is the world we live in. This is the culture we’ve been told to want. These are the messages our children pick up – not just from where they live, but from the shows they watch, the movies they see, the songs they hear, the friends they make and even in their schools. And thanks to social media, AI technology, filters and photoshopping, it’s only getting worse.

So, we need to do whatever we can to combat all of this.

My research shows we have a huge problem on our hands. If a child is already steeped in these gender stereotypes and dysmorphic body ideals by age 5, just imagine what she’ll be thinking by 15.

It’s our responsibility to do whatever we can to foster healthier values and provide more diverse images and ideas of what it means to be a girl, a boy and a human being. I want my daughters – and everyone else’s kids – to always be able to recognise their own unique beauty, and I want them to know their value does not depend on that beauty.

This piece was originally published in May 2024 and is being rerun now as part of HuffPost Personal’s “Best Of” series.

May Ling Halim, Ph.D., is a developmental psychologist and is a mother of two girls. She is a Professor of Psychology at California State University, Long Beach, and the Director of the Culture and Social Identity Development Lab. Her research focuses on gender identity development among diverse young children. Her work has been published in leading academic journals on child development.

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