A study published in the Journal for Bone and Mineral Research this summer suggests that excessive TV watching during childhood may be associated with lower bone mineral content in young adulthood.

The researchers followed 1,181 children over time and measured their weekly hours of TV watching at ages 5, 8, 10, 14, 17 and 20. The bone mineral content (BMC) of each was measured at age 20. The study found that individuals that routinely watched more than 14 hours a week had lower BMC for their whole
body and in their arms than those that watched less. Higher BMC helps protect the body against osteoporosis later in life.

While all screen time should be monitored in children, TV appears to be the most harmful medium. A report published in the Archives of Pediatric and Adoles- cent Medicine studied 111 children between the ages of 3 and 8 and measured their TV viewing and other screen time, as well as their blood pressure levels. The study linked higher blood pressure with excessive TV viewing, but did not nd the same link between the condition and computer usage.