NHS England is set to introduce a sugar tax on snacks and drinks sold in its hospitals in an effort to tackle the UK’s obesity crisis.

As revealed to The Guardian by NHS England chief executive Simon Stevens, the tax will be applied to hundreds of acute, mental health and community service hospitals and every local health centre by 2020.

Stevens also urged ministers to take wider action on sugar, backing all the recommendations recently made by Public Health England, including a national sugar tax, and calling for a mandatory reformulation of food products to cut sugar levels.

Stevens said: “We will be consulting on introducing an NHS sugar tax on various beverages and other sugar-added foods across the NHS, which would be enforced over time as contracts for food catering and the shops that are in the foyers of hospitals come up for renewal over the next three to five years on a rolling basis.”

He added: “By 2020, we’ve either got these practices out of hospitals or we’ve got the equipment of a sugar tax on the back of them.”

biggest cause of lifestyle-linked diseases

He pointed out that bad diet had recently overtaken smoking to become the biggest cause of lifestyle-linked diseases and attacked shops for fuelling obesity with two-for-one offers on cakes, biscuits and other sugary treats and locating these products close to checkouts.

Stevens said the tax was also about keeping the NHS able to function, with levels of type 2 diabetes, a disease linked to bad diet, putting severe and increasing strain on services.

He said: “It’s not just the wellbeing of people in this country and our children. But it’s also the sustainability of the NHS itself.”

The move comes as the government finalises its strategy on dealing with childhood obesity and in the wake of David Cameron’s refusal to rule out introducing a national sugar tax, although he did add that it was something he would rather avoid.