LONDON (AP) – Here's a new warning from health experts: Sitting is deadly.

Scientists are increasingly warning that sitting for prolonged periods – even if you also exercise regularly – could be bad for your health. And it doesn't matter where the sitting takes place – at the office, at school, in the car or before a computer or TV – just the overall number of hours it occurs.

Research is preliminary, but several studies suggest people who spend most of their days sitting are more likely to be fat, have a heart attack or even die.

In an editorial published last week in the British Journal of Sports Medicine, Elin Ekblom-Bak of the Swedish School of Sport and Health Sciences suggested that authorities rethink how they define physical activity to highlight the dangers of sitting.

While health officials have issued guidelines recommending minimum amounts of physical activity, they haven't suggested people try to limit how much time they spend in a seated position.