The increasing body weight across age groups around the world is enhancing the fear that weight related medical problems are bound to increase in the coming years. Halting this trend is apparently not as easy as expected in spite of he widening medical knowledge. In all age groups, an important primary problem is an imbalance in the amount of calories consumed and the energy expenditure, leading to eventual storage in the body as fat. In adolescents, the amount of time spent watching television and playing computer games is an important factor that ensures physical inactivity and prevents the body’s attempt to burn excess calories. In a recently published study, one additional hour of television viewing was associated with a 20 – 30% chance of being overweight, but what is intriguing about their findings is that parental weight played a greater role in influencing the effect of television viewing.
In a review of 1483 youths and their parents, parental weight “moderated the relationship between hours of TV viewing and overweight status among adolescent girls and boys, but not among younger children”. This influence was more glaring in adolescent girls as television viewing predicted increases in the weight when parents were overweight but not in girls with normal weight parents. This appears to suggest that television viewing or playing games on their own may not be as important as previously thought in causing weight increases, even if the sedentary habit theoretically diminish energy expenditure.
This observation means there are more important factors that influence weight gain and we should all take them seriously. While it is true that inactivity predisposes to weight gain, another way to look at it is that children whose “levels of physical activity are low may be watching more TV than active children”. Television watching is sadly related to poor eating habits such as increased snacking and consumption of high fat and high sugar containing foods, which are linked to increases in body weight.
Surprisingly, it appears that the amount of calories consumed and the degree of physical activity are poorly related to weight changes when parental weight is excluded. This brings us sadly back to a basic fear, that weight gain and obesity maybe mainly genetic as shown by the fact that parental obesity is a strong predictor of overweight and obesity in children and that parental pattern of television viewing also influences their children’s choices. It is also true that parents who support their children’s participation in physical activity produces active children. In the end it appears that after all, it is all in the genes.
Steffen L M, Dai S, Fulton JE, Labarthe DR (2009). Overweight in Children and Adolescents Associated with TV Viewing and Parental Weight (Project Heart Beat!). American Journal of Preventive Medicine.