Changes in the ideal of what is considered a perfect body and the trend in recent years to consider a strong, athletic figure as such for both boys and girls is changing the way preteens and teens perceive their body weight.

At least that is one of the main explanations with which an international group of researchers justifies the differences they have observed when studying the temporal trends in the perception of weight of more than 745,000 adolescents from 41 countries in Europe and North America, among whom Spain is also listed.

Specifically, the researchers examined data on 746,121 children ages 11, 13, and 15 collected at four-year intervals between 2002 and 2018 in a WHO collaborative study and found that fewer tweens and adolescents are perceiving themselves overweight and more those who underestimate their body weight.

And this aspect, that they show less and less sensitivity to appreciate that they have excess kilos, worries the authors of the work because it can reduce the effectiveness of public health interventions aimed at preventing and alleviating the growing obesity epidemic.

“During this impressionable age, the perception of body weight can influence a young person’s lifestyle choices, such as the amount and type of food they eat and their exercise habits,” says the lead author of the paper. study, Anouk Garaets, from the Department of Social Sciences at the University of Luxembourg.

That is why Garaets considers that “it is worrying that we are seeing a trend in which fewer adolescents perceive themselves to be overweight (having it), since that could undermine ongoing efforts to address the increasing levels of obesity in that age group because, if Young people do not consider themselves overweight, may feel they do not need to lose pounds, and may make unhealthy lifestyle choices as a result.”

In this sense, the researchers have detected that boys and girls who live in countries with a higher prevalence of overweight and obesity were more likely to underestimate their own weight and less likely to overestimate it, which could indicate that they may have become habituated in some way. and “normalized” having extra kilos.

However, Geraets points out in an email conversation, “although the rate of overweight and obesity is associated with adolescents’ perception of body weight, we have not seen it affect the changes we have observed over time.”

These changes, as well as the differences observed between boys and girls, the researchers suspect have more to do with the evolution of the body ideal for both sexes.

In this sense, the research -published in Child and Adolescent Obesity- found that, throughout the years studied, the correct perception of weight has increased among girls while it has decreased among boys. “The increase in underestimation and decrease in overestimation of the weight status of girls over time can be explained by the emergence of a strong, athletic body as a new contemporary body ideal for both sexes,” the researchers explain.

This could mean that they are moving away from the model of extreme thinness of previous decades while for them the pressure to expand and muscle grows at a very early age.

These trends in body perception over time are somewhat different in the case of Spain. “We have not analyzed country-by-country gender differences, but at a global level Spain showed a significant increase in the correct perception of weight and a decrease in overestimation, while underestimation did not change significantly between 2002 and 2018” unlike what that is observed in the total population of the study, summarizes Geraets in conversation with La Vanguardia.

In 2002, the first year for which data was collected, 60.7% of the Spanish preadolescents and adolescents surveyed had a correct perception of their weight, and this group has been increasing at a rate of 0.6% per year, indicates the researcher .

With regard to the percentage of underestimation and overestimation of weight, in 2002 they were 14% and 25.2%, and the former has practically not changed while the latter has decreased slightly.

All of this coincides with a reduction in the rate of overweight and obesity in the Spanish adolescents studied, something that does not occur in other countries or in the entire population analysed, notes Geraets.

He stresses that, if anything, “more research is needed to understand the factors underlying these temporal trends in order to develop effective public health interventions.”