Increased screen time linked to weight gain in young boys
Published on 15 October 2021
An ongoing longitudinal study says that the two are related. The study’s findings show that there is a relationship specifically between screen-viewing and greater body fat in boys, aged five and below.
A Singaporean study has found that screen-viewing time can lead to greater body fat, specifically among boys aged five and below. This gender-specific discovery was noted in the ground-breaking study carried out in 2011 and 2021, that investigated the potential connections between time spent watching screen devices (such as television and electronic handheld devices) and adiposity (also known as body fat), in children under five years of age.
The study drew data from the Growing Up in Singapore Towards Healthy Outcomes (GUSTO) cohort, a long-term birth cohort study that was initiated in June 2009 to investigate Singaporean mothers and their children’s health and well-being.
Taking into account about 1000 children, the researchers noted the average screen-viewing time for two- and three-year-olds, as well as height, weight and skinfold thickness for three-, four- and five-year-olds. Additionally, belly fat volumes were measured using magnetic resonance imagining (MRI) at 4.5-years-old among subset of around 300 children.
The findings showed that there were links between screen-viewing and body fat in boys, but not in girls. In boys, there was an average increase of 0.12kg/m2 body mass index (BMI) and 0.68 mm skinfold thickness for every additional hour of daily screen-viewing. BMI is the weight-to-height ratio that is often used as an easy guide to measure body fat. Similarly, skinfold thickness is also used as an assessor of body fat percentage. Further research shows that there was an average increase of 24.3 mL, 17.6 mL and 7.8 mL superficial subcutaneous, deep subcutaneous and visceral belly fat tissue volumes, respectively, for every additional hour of daily screen-viewing among boys. Belly fat is considered as better predictor of cardiometabolic diseases than BMI.
In regards to the gender-specific findings, the exact relationship has yet to be determined as further investigations into the data still need to take place. However, researchers proposed several possible reasons for these results: They theorised that screen-viewing time displaces physical activities in boys, resulting in more sedentary behaviour. Comparatively, girls were more likely to engage in non-screen-based sedentary behaviour, so the impact of the screen-viewing time may not be as pronounced on the latter.
“Boys might be naturally or socially encouraged to engage in physical activity when not watching screen devices. In contrast, girls might engage in other sedentary activities more frequently, as reported in a study with older children,” said Ms Natarajan Padmapriya, PhD student and lead author of the study, Saw Swee Hock School of Public Health, National University of Singapore.
Furthermore, Ms Padmapriya shared that “The GUSTO study previously reported sex differences in fat volumes among children. Hence, anatomical differences and the role of sex hormones in the metabolic profile could also explain the sex differences in these associations.”
What could happen next
Screen-viewing and the use of digital devices have become more commonplace in our modern societies, and young children have not been spared from this burgeoning phenomenon. Moreover, this early childhood period is critical for behaviour forming that continues on towards adolescence and adulthood.
“Our results raise the possibility that reducing screen-viewing time for young children and channeling their attention to other non-sedentary behaviours such as active play, could possibly prevent adverse health outcomes later in childhood and over the life course,” said A/Prof Falk Müller-Riemenschneider, Saw Swee Hock School of Public Health, National University of Singapore, and senior author of this study.
Furthermore, the researchers investigated the differences in screen devices and discovered that handheld devices showed a stronger association with increased belly fat volume. “The current data does not explain why different types of screen-viewing are differentially associated with fat volumes. However, it has been suggested that concurrent eating while watching screens, the influence of food advertisements, and insufficient physical activity and sleep, due to the longer duration of screen-viewing, might explain the observed associations,” said Ms Padmapriya.
Moreover, screen time is on the rise within this young age set. A/Prof Muller-Riemenschenider and his colleagues reported that screen-time has increased from 60 to 120 minutes between the ages of six and 24 months. Recent data has also suggested that the COVID-19 pandemic period saw a further increase in the amount of screen-viewing among children.
The GUSTO study also showed that two to three year-olds spend 2.5 hours per day on average watching screen devices, comprising one hour and 40 minutes of television watching and nearly an hour on handheld screen devices. This number is significantly higher than the WHO guidelines that recommend children under the age of two avoid screen time completely, and for those aged two- to four-years, screen time should be no more than one hour.
The study also posited that excessive screen-viewing and related increased in body fat may have significant effects on other poor health outcomes, including coronary heart disease and Type 2 diabetes.
What can be done
With these findings, parents can make conscious decisions to intervene should they find that their children currently indulge in too much screen time. “Parents should aim to reduce their children’s screen viewing on all types of screen devices, including TV, electronic sedentary video games and also handheld devices, such as tablets and smartphones,” said Ms Padmapriya.
She suggested the following methods to help parents manage this information:
Replace screen view with interactive sedentary activities, such as storytelling, playing board games and singing.
Replace sedentary time with active play and physical activity.
Setting screen viewing rules for their child based on the latest guidelines:
Eliminate background TV or other screen devices while taking meals, playing with toys or during family conversations.
Watch TV or other screen devices only in the living room and avoid TV or other mobile screen devices in the child’s bedroom.
Do not leave the child unattended: monitor the screen’s media content, select high-quality programs adapted to the child’s age, engage in conversations with the child about what is watched (within the time limit).
In consultation with A/Prof Falk Müller-Riemenschneider, Saw Swee Hock School of Public Health, National University of Singapore, and Ms Natarajan Padmapriya, PhD student and lead author, Saw Swee Hock School of Public Health, National University of Singapore.
Padmapriya N, Aris IM, Tint MT, Loy SL, Cai S, Tan KH, Shek LP, Chong YS, Godfrey KM, Gluckman PD, Lee YS, Saw SM, Yap F, Kramer MS, Bernard JY, Müller-Riemenschneider F. Sex-specific longitudinal associations of screen viewing time in children at 2-3 years with adiposity at 3-5 years. Int J Obes (Lond). 2019 Jul;43(7):1334-1343. doi: 10.1038/s41366-019-0344-x.
Padmapriya N, Tint MT, Sadananthan SA, Michael N, Chen B, Cai S, Toh JY, Lanca C, Tan KH, Saw SM, Shek LP, Chong YS, Gluckman PD, Lee YS, Yap F, Fortier MV, Chong MF, Godfrey KM, Eriksson JG, Velan SS, Kramer MS, Bernard JY, Müller-Riemenschneider F. The longitudinal association between early-life screen viewing and abdominal adiposity-findings from a multiethnic birth cohort study. Int J Obes (Lond). 2021 Sep;45(9):1995-2005. doi: 10.1038/s41366-021-00864-9.