DESK jobs and lazy nights in front of the TV kills nearly 70,000 a year and costs the NHS £700million, a study says.
Experts are urging those who sit for six hours or more each day — at work or at home — to be more active at other times.
Past studies have shown that spending large parts of the day seated can increase the risk of cardiovascular disease, Type 2 diabetes, cancer and death.
Researchers say more than one in ten deaths is linked to a sedentary lifestyle, equating to 69,276 per year.
They have estimated the financial impact on the NHS for the first time — and claim it is around £700million.
But the true figure may be higher as the analysis did not include musculoskeletal conditions or mental health disorders.
Lead author Leonie Heron, of Queen’s University Belfast, said: “Measures should be taken to reduce sedentary behaviour with the aim of improving health and reducing the financial burden to the health service.”
But Prof Naveed Sattar, of the University of Glasgow, had reservations over the findings.
He said: “Being unwell makes people sit more rather than the other way around.”