* WHO orders the first guidelines for children under 5 years of age
* Recommended physical activity, good sleep, limited screen time
* Obesity rates rising to children, children around the world
by Stephanie Nebehay
GENEVA, April 24 (Reuters) – Children aged two to four should not be allowed more than an hour of "sitting on the screen" every days and babies under one year old should not be exposed to electronic screens, the World Health Organization (Wednesday said on Wednesday.
The United Nations agency, who provided his first such rules, said that under-fives should be physically active and get enough sleep to help build a lifelong lifestyle and avoid obesity and other life-threatening disorders or.  Leisure time will include watching television or videos and playing computer games.
"Healthy physical activity, well-adjusted habits and sleep habits are established early in life, giving a chance to shape h Children between one and four years should spend at least three hours of different physical activity that spreads throughout the day, it says.
Inactive is a "top risk factor" for mortality and stress in the global increase in overweight and obesity, the WHO said.
In a report two years ago, the WHO said that the number of obese children and young people around the world jumped ten times to 120 million over the past 40 years and the increase has accelerated in low- and middle-income countries, especially in Asia.
Overweight can lead to diseases including diabetes, hypertension and certain types of cancer, it said.
Early childhood is a period of rapid physical and cognitive development during which habits are developed and family lifestyle activities are adaptable, It says in rules, from in evidence of hundreds of studies, many from Australia, Canada, South Africa and the United States.
"Unusual behavior, when riding a car instead of walking or biking, watching TV sit or playing inactive screen-based games is increasingly worsening and relate to poor health outcomes, "states WHO.
Serious inadequate sleep in children is associated with an increased excessive accumulation of fat as measured [BMI].
The shorter duration of sleep is associated with more TV viewing and time spent playing computer games, added.
"Improving physical activity, always sitting and time behavior of children can help their physical health, reduce the risk of developing childhood obesity and associated non-communicable diseases to life later and to improve mental health and wellbeing, "states WHO. (Reporting by Stephanie Nebehay Editing by Gareth Jones)
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