Three main myths have driven weight policy, interventions, and practice over the past 10-15 years:
1) that people at higher weights must be eating more and not exercising enough
2) that hating your body, or being ashamed by it, will motivate you to lose weight, and
3) that you need to know that you are overweight to motivate you to do something about it,
However, recent, high quality scientific evidence over the past 5-years has busted these myths, big time. Let’s look at them one by one.
Myth 1: Larger kids must eat more
Research with adolescent boys and girls in Lithuania has looked at the nutrition habits of adolescents according to their weight status as determined by their Body Mass Index [BMI; an imperfect measure, but that’s a whole other article].
The only difference in nutrition habits of larger bodied boys was that they ate less fruits and berries.
Girls in larger bodies were less likely to eat sweets (cakes, candies, chocolate), fats spreads, and oils, and were less likely to eat breakfast.
There was no difference in the amount of physical activity that the adolescents in different weight categories engaged in.
The go-to image of news outlets, of the larger bodied, usually headless, person shovelling fast food into their mouths just isn’t representative of their usual diet. It turns out that adolescents in different weight categories don’t actually have significantly different nutrition and eating habits, and when there were differences (like in the girls in higher weight categories), they are the opposite of what was expected.
Myth 2: We should teach body hate to get people to lose weight
Time and time again we see the public health campaigns, or the advertisements for weight loss companies and gyms that use words and imagery designed to make us feel bad enough about how we currently look to want to use their product or service. Although this might gain attention and even action in the short term, it’s a really bad way to motivate long term engagement in healthy behaviours that would support reaching a healthy body weight. Here’s why.
Having a high BMI is actually the number one risk factor for body dissatisfaction. Research from around the world confirms that those at higher BMI’s are more likely to be dissatisfied with their bodies, and have lower self-esteem, and Quality of Life. This is found again and again in research studies in countries as diverse as Kuwait, Spain, Portugal, Lithuania, and the USA. This tells us that those who are at a high weight are already experiencing high levels of body dissatisfaction, it doesn’t need to be induced in order to promote action.
Body dissatisfaction also doesn’t lead to weight loss- instead, longitudinal research from the USA tells us that those who have high levels of body dissatisfaction, and engage in disordered eating behaviours, are more likely to GAIN weight over time, not lose it. This was shown to be true for adolescents over a 5-year, and 10-year follow up period.
Myth 3: Kids should be told that they are overweight in order to ‘help them’ get healthy
In the Lithuanian study, when adolescents over-estimated their weight, they were more likely to be dissatisfied with their bodies, want to be thinner, be self-conscious about their bodies, engage in disordered eating, and have low self esteem, and this was stronger for girls than boys. It turns out that, having a high BMI, and thinking that your weight is too high, are equally detrimental for girls’ body image and self esteem
Among adolescents in the USA, ‘weight misperceivers’- adolescents whose BMI was in the overweight or obese range, but who thought that they were in the ‘health weight’ range- were more likely to engage in physical activity, consume fruit and vegetables, and meet sleep guidelines, than those who were in the overweight range, and knew it. Weight misperception (believing you are in a healthy weight range when you are in higher weight categories) seems to be protective in terms of supporting people to maintain their weight and engage in healthy behaviours. This has also been found among adolescents in Taiwan.
What does this mean?
It’s time for a radical change in our approach around weight. The current approach to media, policy, and school-based programs that focus on obesity and weight loss can have a detrimental effect on adolescents for life
When politicians and policy makers are making suggestions about BMI report cards, they should take note- when young people are told that their BMI is in the overweight or obese range, they engage in less healthy behaviours – including exercise, and longitudinal studies show that they gain more weight over time.
If our goal is to improve adolescents’ eating and exercise behaviour, we are better off supporting their body image and self-esteem than encouraging weight loss. We should be teaching the next generation that healthy behaviours are for everyone, regardless of appearance, and to be critical of advertisers and governments who promote weight loss at all costs.
Zali Yager is an Associate Professor in Health and Physical Education at Victoria University in Melbourne, Australia. She is an expert in the school-based promotion of positive body image for children and adolescents.