School bags can be a serious threat to the spinal health of children and must not exceed ten per cent of the body weight of the children, experts warn. \"The most obvious reason for back pain amongst children is carrying unsuitable back packs,\" Dr Neda Nafei, chiropractor at Top Medical Center, said. Back pain in children could be due to various factors such as age, pre-existing back conditions such as hereditary scoliosis (spine curves away from the middle or sideways), playing sports, and gender, she said. A significant increase in back pain incidents occurs at the age of 12 and over. Also, females are more likely to experience back pain than males, Dr Nafei said. Article continues below \"Children who watch television for extended periods are more likely to have back pain. That includes time spent behind computers or playing video games, especially in a slouched position. More importantly, prolonged sitting behind the not-so-ergonomically-correct desks at schools plays a major role in development of back pain.\" Cause for concern Children should also be informed against carrying the bag over one shoulder. Incorrectly packed and ill-fitting school bags are a reason for concern, especially because of the long number of years children spend in school, Dr Nafei said. \"Many children are carrying heavy school bags and hurt themselves,\" Dana Diab Halabi, physiotherapist at Cosmesurge and Emirates Hospital Clinics, said. If children are suffering from headaches, neck ache, bad posture, decreased performance, strained muscles, lower back pain, tingling hands, and increased scoliosis complications, they are carrying too much weight, she said. No one should carry more than 11 kilograms in a backpack. \"Statistics show that students are sitting 1,000 hours per year and carry a school bag around 300 to 400 hours per year,\" said Dr Nafei.