I struggle with my weight, says Boris Johnson as he launches obesity strategy
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He said he was "way overweight" when he was admitted to intensive care in April as he battled Covid-19 and was put on oxygen.
A report published on Friday from Public Health England (PHE) found that being overweight or obese can dramatically increase the risk of hospitalisation and death from coronavirus.
Mr Johnson said: "I've always wanted to lose weight for ages and, I think like many people, I struggle with my weight - I go up and down.
"But since I recovered from coronavirus, I've been steadily building up my fitness.
"I don't want to make any excessive claims because I've only really just started concentrating on it, but I'm at least a stone down, I'm more than a stone down.
"But when I went into ICU (intensive care) when I was really ill... I was way overweight. I'm only 5ft 10.
"I start the day by going for a run with the dog, quite a gentle run but actually getting faster and faster now as I get fitter.
"There are health reasons, but it also makes you feel much better.
"And that's the number one thing, you actually have more energy if you can get your weight down.
"And the other thing is that if you can get your weight down a bit and protect your health, you'll also be protecting the NHS."
Mr Johnson said people did not need to go to a gym to exercise and aid their weight loss.
"Gyms are great, but you don't need to have a gym," he said.
"There are amazing things on your phone these days, amazing apps, fantastic trainers that you can watch on YouTube.
"What we're doing now with our Better Health strategy is to try to help people a little bit to bring their weight down.
"Not in an excessively bossy or nannying way, I hope.
"We want this one really to be sympathetic to people, to understand the difficulties that people face with their weight, the struggles that everybody faces... and just to be helpful."
The new obesity strategy launched on Monday sees an end to confectionery displays at store checkouts and a ban on adverts for foods high in fat, sugar and salt on TV before 9pm.
Deals such as 'buy one get one free' on unhealthy foods will also be banned, while alcoholic drinks could soon have to list their calorie content.
Placing sugary and fatty items in prominent locations in stores will be stopped, including at checkouts and entrances, and online.
Instead, shops will be encouraged to promote healthier choices and offer more discounts on healthy food such as fruit and vegetables.
The Government will also hold a short consultation on whether the ban on online adverts for foods high in salt, sugar and fat should apply at all times of day.
It says evidence shows that exposure to such advertising can affect what and when children eat by shaping their preferences at a young age.
When it comes to calorie labelling, new laws will require large restaurants, cafes and takeaways with more than 250 employees to add calorie labels to the food they sell.
A new campaign to help people lose weight, get active and eat better after Covid-19 is also being pushed out as a "wake-up call" to the nation.
This will include more self-care apps and online tools and accelerating the NHS Diabetes Prevention Programme.
From next year, doctors will be offered financial incentives to ensure those who are obese are supported to lose weight, such as prescriptions for exercise and bike rides.
GP practice staff will also have the opportunity to become "healthy weight coaches" though training delivered by PHE.
Health Secretary Matt Hancock, writing in the Daily Telegraph, said: "If everyone who is overweight lost five pounds it could save the NHS over £100 million over the next five years.
"And more importantly, given the link between obesity and coronavirus, losing weight could be lifesaving."
Two-thirds of UK adults are above a healthy weight, according to Government data, and one in three children aged 10 to 11 are overweight or obese.
The highly interventionist approach marks a U-turn for Mr Johnson, who until recently has been a vocal opponent of "sin taxes" and perceived "nannying" by the state.
But Mr Johnson looks to have dropped his libertarian stance for a plan designed to save the NHS time and money while also helping to reduce the number of Covid-19 deaths in a possible second wave of infections.
The Obesity Health Alliance, a coalition of more than 40 leading health organisations, medical royal colleges and campaign groups, praised the targeting of promotional offers.
But UKHospitality chief executive Kate Nicholls criticised the timing of the extra impositions on restaurants and pubs.
"As we focus on securing jobs and helping the economy and communities to recover, a raft of costs and regulatory burdens would be a slap in the face," she said.