Women feeling unhappy with their bodies and their size in our society is so common, it’s sometimes described as a “normative discontent”. Typical studies find that somewhere between 70 and 90% of adolescent and adult women would like to be thinner or lose weight.

But does that matter? Maybe women should be a bit less vain? Maybe if you’re overweight it’s a good thing to feel bad about your body, it might make you lose weight? Well – studies with follow up over a few years suggest that feeling bad about your body has some pretty negative consequences – it puts you at higher risk of eating disorders (surprisingly common, and very serious illnesses). It has also been found to increase the likelihood that you will gain weight – feeling bad about your weight doesn’t tend to lead to losing it.

We wanted to see if we could better understand one of the factors that might lead to this unhappiness – seeing images of other women’s bodies. There have been lots of studies that have shown that looking at photos of very slim and glamorous models, compared to, say, pictures of beautiful gardens, tends to make women feel bad about their bodies. There have been a few studies that have suggested that looking at pictures of glamorous underweight models make women feel worse than looking at plus-size clothing catalogue models. But we couldn’t find any studies that used the same women, stretched to appear to be different sizes, and studied the effect of seeing such images on women’s view of how thin or fat they were, and how happy they were with their size.

Our paper (open access to everyone if you like your science with more detail) describes two studies we carried out, both in 18-25 year olds with a Body Mass Index in the healthy range. The first study comprised 90 women and the second 96 women – the main difference between the two studies was that in the second we selected women who reported being very dissatisfied with their body in our screening questionnaire. In each study, we randomly allocated each woman to do a 15-minute computer task in which they looked at computer images of other normal women: one group saw images of 10 normal women with a BMI in the the middle of the normal range; one group saw images of the same women, stretched a little to make them look a bit larger; one group saw images of the same women made slightly slimmer. Before and after the task they rated the size of some other women’s bodies, and their own body, and how satisfied they were with their body size.

We found that, particularly in the second group where women were more dissatisfied with their bodies to start with, they viewed both others’ bodies, and their own bodies as smaller if they had seen the larger images as opposed to the smaller images. And they felt more satisfied with their own body size after they had seen the larger images as opposed to the smaller ones.

These weren’t perfect studies, there were various things we could improve – for example, most of our participants were students from the University of Bristol – they might not be representative of the whole population. We don’t know what effect, if any, these images might have for people who are currently overweight, or underweight. The studies are only in women, so we don’t know whether the same things might happen for men.  We could have manipulated the images in a more sophisticated way than we did. Maybe our participants guessed what we were hoping to find and altered their responses to fit in.

But we think we have found something interesting, and something that as a society and as individuals we could use to help women feel better about their body size. The mainstream media could mix up its images, use a wider variety of models of different weights, and stop airbrushing them so thin. And on social media, if you want to feel better about the way you look, you could try editing your feed so you aren’t getting a constant stream of skinny. You could even post an untouched-up selfie that isn’t the best one of the hundred you took. We need to have a reminder of what normal looks like.