Desk jobs may increase chances of heart attack: Study

If you work in a desk-bound job and spend too much time sitting down, you may have a bigger waistline and increased risk of heart disease, a new study has warned.

The study suggests that waist circumference increases by two centimeters and risk of cardiovascular diseases by 0.2 per cent, for every additional hour of sitting on top of five hours, researchers said.

Also, bad cholesterol (LDL) increases and good cholesterol (HDL) decreases with each additional hour of sitting from five hours a day, they said.

The study led by William Tigbe from University of Warwick in the UK advises people to sit less and be more active.

Standing for as much as seven hours a day, and walking seven miles, may be needed to avoid heart disease, according to the study.

Tigbe kitted out 111 healthy postal workers with activity monitors for seven days; 55 were office workers and 56 delivered post for a living.

The study found that those who had desk jobs had a bigger waist circumference - 97 cm compared to 94 cm - and about one Body mass index (BMI) unit difference.

They also had a higher risk of cardiovascular disease -2.2 per cent compared to 1.6 per cent over ten years. BMI is a measure of body fat based on height and weight.

Only healthy, non-smokers, with no personal history of myocardial infarction (heart attack), stroke, coronary heart disease, hypertension or diabetes were included in the study. None of the participants was on any lipid, blood pressure or glucose lowering medication.

"Our evolution, to become the human species, did not equip us well to spending all day sitting down. We probably adapted to be healthiest spending seven to eight hours every day on our feet, as hunters or gatherers," said Professor Mike Lean from University of Glasgow in the UK.

The research was published in the International Journal of Obesity.