Girls obese at age 11, 13 and 16 linked to adverse impact on grades
According to the CDC, childhood obesity has more than doubled in children and quadrupled in adolescents in the past 30 years. In 2012, more than one third of children and adolescents were overweight or obese. Childhood obesity has both immediate and long-term effects on health and well-being including risk factors for heart disease, prediabetes and bone and joint problems.
Now a new study finds that tween girls who are obese at age 11 had lower academic achievement at ages 11, 13, and 16 when compared with healthy weight tweens, even after factoring out a number of possible influences, including IQ.
Overweight or obese adolescence may face negative effects on academic achievement; however the evidence is limited to cross-sectional studies with small samples and lack of con-founders. This new study is the most comprehensive to date.
In this new study led by Dr. Josephine N. Booth, PhD, School of Psychology at the University of Dundee and colleagues tested the hypothesis that adolescent obesity independently influences academic attainment.
In this longitudinal study researchers examined data from the Avon Longitudinal Study of Parents and Children (ALSPAC), a long-term health research project. Participants height and weight were measured with healthy weight defined as BMI Z score <1.04; healthy weight, BMI Z score 1.04 – 1.63; overweight and BMI Z score >1.64; obese. Body mass index z-scores, are measures of relative weight adjusted for child age and sex. Academic achievement was also assessed by national tests of 5,966 children. At age 11 71.4% (1,935 male; 2,325 female} were healthy weight, 13.3% (372 male; 420 female) were overweight and 15.3 % (448 male; 466 female) were obese. The researchers followed the participants for the next five years.
Overall the results showed girls obese at age 11 had lower academic attainment at 11, 13 and 16 years compared to those of healthy weight even after controlling for a wide variety of con founders including socioeconomic status, mental health, IQ and age of onset of the menstrual cycle. Associations between obesity and academic attainment were less clear in boys. Mental health, IQ and age of onset of the menstrual cycle did not affect the link.
In their conclusion the researchers write “For girls, obesity in adolescence has a detrimental impact on academic attainment five years later. Mental health IQ and age of menarche did not mediate this relationship, suggesting that further work is required to understand the underlying mechanisms. Parents, Education and public health policy makers should consider the wide reaching detrimental impact of obesity on educational outcomes in this age group.”
“This study suggests that obesity in adolescence is associated with poorer subsequent academic attainment for females, and that the magnitude of the relationship may be considered important.” “Moreover, the present study suggests that the relationship between obesity and subsequent academic attainment is likely to be causal.”
Dr. Booth commented “There is a clear pattern which shows that girls who are in the obese range are performing more poorly than their counterparts in the healthy weight range throughout their teenage years."
Dr. John Reilly, University of Strathclyde and principal investigator of the study commented "Further work is needed to understand why obesity is negatively related to academic attainment, but it is clear that teenagers, parents, and policymakers in education and public health should be aware of the lifelong educational and economic impact of obesity."
The results of this study are published in the International Journal of Obesity.