A group of directors of public health in England has written to the prime minister, calling for any anti-Covid-19 obesity plan to address the underlying causes of unhealthy weight, from poverty to the easy availability of junk food. Boris Johnson is expected to announce a new strategy to get the nation lighter and fitter, triggered by his own encounter with coronavirus. Obesity is a risk factor for severe disease. Johnson now recognises his own obesity was partly responsible for his stay in intensive care and he is said to have lost weight since. Eight directors of public health from the north-west of England have signed the letter, calling for more than a quick fix. They want the government to “create an environment that support individuals to make changes in their behaviour, making it easy for people to make the healthy choice,” they write. “Without this, a national campaign encouraging weight loss would be entirely ineffective and a waste of taxpayers’ money. There is simply no point in addressing the symptoms and ignoring the causes. “Our weight status is not solely dependent on our personal choices. There are many other significant factors that determine one’s weight – including where we live, how much money we earn, who we socialise with, what marketing we are exposed to, our family history and many more factors.” Matthew Ashton, lead director of public health for Food Active, a healthy weight campaigning group funded by local authorities, and one of the signatories, said it was not enough just to recruit the TV fitness coach Joe Wicks to get the nation’s schoolchildren moving, as some newspapers have suggested is on the cards. “We know this isn’t just physical activity. It’s energy in, energy out,” said Ashton. “You have to do a hell of a lot of energy-out stuff to compensate for the large amounts of energy we are all as country taking in because of the way our food systems are set up – the processed foods, the sugar intake we all have. The sweets and pointless food we all enjoy having but that really doesn’t do us any good means you have to do a hell of a lot of physical activity to get rid of it. “Clearly physical activity has to be a key part of the strategy, but it is the one we always point at. Commercial sponsorship of sports – the likes of Mars, Coca-Cola, Lucozade – those kind of things which are high-energy, high-input products – kind of get away with it by then supporting physical activity opportunities in the community. But actually it would be so much better if we didn’t have the stuff going in in the first place.” What is needed is cultural change, he said, so that people don’t grab food on the go while rushing about their daily lives, and have “a takeaway on your lap in front of the telly”. Ideally we would have meal times with our families, where people tend to eat more slowly and can engage with other people, which promotes not just healthy bodies but healthy minds, he said. “My concern is that we do what we’ve always done,” he said. He didn’t want the plan to assume that “we’re a nation of fatties and that’s for individual responsibility to sort out by getting off your backside and going for a run in your park,” he said. “I’d rather that a large portion of this conversation was about what are our society responsibilities here. What are our responsibilities to help everybody be fit and healthy, including having a healthy weight?”