When I was conducting research for my book, 13 Things Mentally Strong Women Don’t Do, I wanted to uncover the reasons why women are more likely to engage in specific unhealthy habits that rob them of mental strength. I knew many of the unhealthy habits start at a young age–so I spent a lot of time examining the research on how girls are raised differently.   

Even during a time when girls are repeatedly told, “You can do anything boys can,” the message isn’t sinking in. Girls continue to internalize a message that says, “Boys are naturally more brilliant.”  

Boys Are Brilliant, Girls Try Hard

A 2017 study looked at 400 children between the ages of 5 and 7. In the first experiment, children were told a story about a person who is “really, really smart.”

Then, they were given photos of two men and two women and asked to identify which person they thought the story was about. The people in the photos appeared to be the same age, equally happy, and dressed professionally.

At age 5, both girls and boys were most likely to identify someone with the same gender, meaning boys picked men and girls picked women as the person they thought was “really, really smart.”

By age 6 and 7, girls were “significantly less likely” to pick women. Both boys and girls chose a man as the person who was most likely “really, really smart.”

In the second part of the study, children were given a choice of two board games to play. One was for “children who are really, really smart,” and the other was for “children who try really, really hard.”

At age 5, girls and boys were equally likely to play the game for smart ids. But at ages 6 and 7, the girls were more likely to opt for the one for kids who try hard while the boys still requested the game for kids who are smart.

So what happens to little girls between the ages of 5 and 7 that cause their beliefs to shift so sharply? It happens to be the timeframe when they start school.

Perhaps all of the scientists, astronauts, and historical figures they learn about are men–which sets the stage for their belief that men must be brilliant.

This may be one of the reasons why it’s tough to attract women to STEM careers–girls grow up believing men are naturally more brilliant.

What We Need to Differently

So how do we prevent girls from developing self-limiting beliefs? The notion that women don’t quite measure up is deeply engrained in our culture and telling girls they’re good enough only scratches the surface.

We’re starting to see some examples of this. For example, toy manufacturer Mattel has tried to change Barbie’s image in recent years by launching the “You can be anything” campaign that shows Barbie can be veterinarians, professors, and paleontologists.

Changing the type of toys we market to girls is one step in the right direction.  But we need to do a lot more.

One big issue we need to tackle is the media girls are consuming. Magazines for adolescent girls focus almost solely on make-up advice and weight loss tips. And social media can give them a skewed sense of what’s really important in life.

And, we need to make sure girls are exposed to brilliant, successful, strong women. Perhaps if girls saw more examples of female engineers, physicians, and scientists, they might be more likely to believe that women are brilliant too.

Originally published on Inc.

Follow us here and subscribe here for all the latest news on how you can keep Thriving.

Stay up to date or catch-up on all our podcasts with Arianna Huffington here.