More ‘Generation Z’ boys and girls in the UK are dieting to lose weight than in previous generations, and are likely to overestimate their own weight, finds a new UCL-led study.
The research, published in JAMA Pediatrics, found that girls who are trying to lose weight are also more likely to experience depressive symptoms than in previous decades.
In 2015, 42% of 14-year-old girls and boys said they currently were trying to lose weight, compared to 30% in 2005.
Lead author Dr Francesca Solmi said: “Our findings show how the way we talk about weight, health and appearance can have profound impacts on young people’s mental health, and efforts to tackle rising obesity rates may have unintended consequences.
“An increase in dieting among young people is concerning because experimental studies have found that dieting is generally ineffective in the long term at reducing body weight in adolescents, but can instead have greater impacts on mental health. We know, for instance, that dieting is a strong risk factor in the development of eating disorders.”
The research team reviewed data from 22,503 adolescents in the UK. They found in 2015, 44% and 60% of all participants had dieted or exercised to lose weight, respectively, compared to 38% and 7% in 1986.
The researchers say other evidence suggests that engagement in vigorous physical activity has remained relatively stable among adolescents over the past few decades.
Senior author Dr Praveetha Patalay said: “It seems that young people are exercising for different reasons than they did before – more adolescents seem to be thinking of exercise predominantly as a means to lose weight rather than exercising for fun, socialising and feeling healthy. We suspect that recent controversial calls to add ‘exercise-equivalent’ labels on food packaging may exacerbate this.”
While girls have consistently been more likely to diet to lose weight, the researchers found a greater increase over the years among boys, who were also becoming more likely to be trying to gain weight.
Both girls and boys also became more likely to over-estimate their weight from 1986 to 2005, and even more so by 2015, which the researchers say adds to their concerns that increased efforts to lose weight are not necessarily due to increased obesity rates.
Dr Solmi said: “Public health campaigns around obesity should consider adverse mental health effects, and ensure they avoid weight stigma. By promoting health and wellbeing, as opposed to focusing on ‘healthy weight’, they could have positive effects on both mental and physical health.”