Does thinking you’re fat, make you fat?

Bad body image might be a self-fulfilling prophecy, a recent study claims, as normal-weight teens who think they're fat are more likely to grow up to be overweight.

"Perceiving themselves as fat even though they are not may actually cause normal-weight children to become overweight as adults," says Koenraad Cuypers, a researcher at the Norwegian University of Science and Technology.

These findings were published this month in the Journal of Obesity.

"The team from the Norwegian University of Science and Technology used a survey of 1,200 normal weight adolescents aged 13 to 19, in which they were asked about their perception of their weight," The Telegraph summarizes the study. "They compared the responses with a follow-up questionnaire eleven years later, examining how many had a Body Mass Index — a measure of weight relative to height — of 25kg per square metre (classed as 'overweight') or 30kg per square metre and above ('obese')."

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The researchers found that half of the study participants were still at a normal weight in adulthood.

However, 59 per cent of the female participants who felt fat in their teens became overweight in adulthood. While only 31 per cent of normal-weight teens who did not consider themselves fat grew up to be overweight.

When obesity was measured by waist circumference instead of BMI, these numbers increased dramatically, with 78 per cent of "fat" teens going up to be overweight and only 55 per cent of teens with better body image growing up to be overweight.

Researchers cite multiple possible explanations for their findings, including psychological stress due to unhappiness with one's body -- which can contribute to gaining weight around the waist.

"Another explanation may be that young people who see themselves as fat often change their eating habits by skipping meals, for example. Research has shown that dropping breakfast can lead to obesity,"says Cuypers.

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Cuypers believes both the school system and the society at large need to work to address these body-image issues which can lead to later health consequences, and wants to see a shift from a focus on weight to a focus on well-being.

"The weight norms for society must be changed so that young people have a more realistic view of what is normal. In school you should talk to kids about what are normal body shapes, and show that all bodies are beautiful as they are," says Cuypers.

"Having normal weight and being satisfied with their weight are favourable factors for an adolescent. Weight perceptions are, however, often unrealistic," the writers conclude in the study.

A 2010 study suggests that all women fear getting fat, even those who claim to not care about body issues. Cuypers' study confirms that those fears and body-image issues in adolescence are more harmful than preventative.

Want to set your kids up for success? Here are 28 ways to teach your children to love their bodies.

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