Curtin University researchers have found children who spend a lot of time watching television, have poorer and weaker bones in young adulthood which could significantly impact their health in later life.
Lead researcher Dr Joanne McVeigh, Curtin’s School of Occupational Therapy and Social Work, said the study examined the TV viewing habits of 1,181 young adults over their childhood and adolescence years and related these to how strong their bones were at age 20.
“Over 40 per cent of study participants watched more than 14 hours of television a week, from ages five to 17. It was this group which experienced between three and seven per cent less bone mass at age 20 compared to those who watched less television,” Dr McVeigh said.
“This relationship remained even after we considered physical activity, calcium intake, Vitamin D status and smoking which are all known contributors to bone health.”
The study found children who watched more than 14 hours of television a week were likely to carry on with this trajectory in later years and this may be linked to the development of weak bones.
Previous research has demonstrated the poorer the bone health in young adulthood, the greater the risk for osteoporotic fracture in later life. Fractures are associated with significant morbidity, mortality, loss of independence, and financial burden.
“Around 1 in 5 people aged 65 and over will die within a year of fracturing their hip so poor bone health is very dangerous in later life,” Dr McVeigh said.
“Given we start to lose bone around the age of 30, young adulthood is a really important time to make sure our bones are as strong as possible to offset later loss.”
The research further suggested less TV watching was also likely to offset other negative impacts such as obesity as more time can be spent being physically active.
“Previous research has found TV watching has been linked with poorer food choices and drinking too many sugar sweetened beverages which is not good for bone health,” Dr McVeigh said.
“It is clearly important that children should develop good TV viewing habits as our study demonstrates that this sets them up for good bone health in later life.
“We would encourage a reduction in TV watching time and other screen time and promote activities which encourage people to be physically active and build the strongest bones possible by young adulthood.”
The research, titled Longitudinal Trajectories of Television Watching Across Childhood and Adolescence Predict Bone Mass at Age 20 Years in the Raine Study, was published in Journal of Bone and Mineral Research.
Funding was provided by Curtin University; Edith Cowan University; Raine Medical Research Foundation; Telethon Kids Institute; and The University of Western Australia.