There is a new lockdown divide: those who have used the time to get healthy and lose weight and those who have slouched a little too much on the sofa crunching crisps and watching TV.

Among the former camp are the priest and journalist, Giles Fraser, who has reversed his diabetes by following a strict diet and exercise regime. Baroness Sayeda Warsi has lost 28 lbs and Mark Essex, Director of Public Policy at KPMG has lost a staggering 100lbs by following the regime of former Labour MP, Tom Watson, which he has written up into a best-selling book. Will Quince, the MP for Colchester, has taken the healthy living so far that his clothes are hanging off him.

In my own home, both my husband and son have been competing to see who could lose the most – they have each shed 10lbs.  I have created a regime for myself which includes 30 minutes of exercise – with help from various trainers on YouTube – and ten thousand steps a day come rain or shine.  The latter of which there has been so much that getting plenty of Vitamin D has not been a problem.

I have chosen to walk the Essex footpaths rather than stare at a screen while listening to Hilary Mantel’s brilliant The Mirror and The Light, reflecting on how familiar the jostling for power and brutality of Henry VIII’s court sounds to us today.

But for those of us who have used this period as an opportunity to get healthier, it appears that many more have slumped unmoving in front of screens and TVs, snacking, eating takeaways and emerging blinking into the post-lockdown world many pounds heavier than when it started in March.

We are emerging from three months of being locked away as either “Hunks, Chunks or Drunks”, as I think the saying goes.  This is happening despite all the evidence that weight and obesity plays a critical role in how vulnerable we are to serious health complications and even death from the virus.

Obesity is linked with type-2 diabetes, heart disease, cancer and now dementia.

As a chubby child and a plump adult, I finally lost 28lbs 10 years ago, and I know how hard it is not just to lose the weight, but to also keep it off.

The Prime Minister’s brush with death was clearly a wake-up call for him, and he and the health team at Number 10 are currently looking at effective policies to try and get the country fitter.  As he recently reminded us, we are the fattest nation in Western Europe. This is not a statistic to be proud of. Not only is this bad for our health as individuals and costing the country a fortune in lost days at work, but it is busting the NHS.  Almost a tenth of our entire NHS budget goes on treating type-2 diabetes alone. A preventable disease which can be avoided and even reversed through healthy diet and exercise.

Three years ago I chaired a report for the Centre for Social Justice into childhood obesity – “Off the Scales: Tackling England’s childhood obesity crisis.”

It was challenging to keep food campaigners and representatives from the retailers in the room together, let alone agree to a set of recommendations.

I know the politics of tackling this problem are extremely difficult. But no child wants to be fat.  All children deserve to have a better, healthier start in life, whatever their background. The statistics are stark. The proportion of obese children doubles during primary school, meaning twice as many children leave primary school obese from when they started.

Obesity is also a matter of social justice. Obesity prevalence for children living in the most deprived areas is more than double that of children living in the least deprived areas, and the obesity gap between rich and poor has been growing since 2005. The obesogenic society we now live in is a fairly new phenomenon.

We are surrounded by temptation, fast food delivered to our doors, bombarded by adverts and images for delicious snacks.  See an advert for Pringles and I can only just resist jumping in the car to buy some.

At the risk of sounding a goody-two shoes, I try and live by the five rules for a healthy life.  Simple, but not easy.  Healthy diet, healthy weight, regular exercise (all of which boost the immune system ahead of a potential second spike), don’t smoke and don’t drink – well don’t drink too much. If we all agreed to do this, we would not only spend less of our life hampered by unnecessary illness, but we would also enjoy a healthier old age and save our NHS from buckling under the collective weight of the nation.

What is the answer? For a start the government needs to implement Chapter Two and Three of its oven ready childhood obesity strategy.

The work has been done, consultations undertaken, and policy promises made. The PM’s preferred option for exercise is not enough (he should know as an active tennis player and keen cyclist) but it should not be left out of a multi-intervention strategy either. The Daily Mile initiative and popular online classes like #PEwithJoe are great at getting kids moving and don’t require any equipment or expensive space, but they must be part of an active nation revolution which provides high quality and well-designed infrastructure for cycling, walking, running, swimming and other traditional sports.

Clinically and morbidly obese people with huge amounts to lose should be considered for bariatric surgery. It is not the easy way out as some may think. Obesity campaigner Angela Chesworth has written about what it takes to go through with it and how for many, it is the only realistic option left.

The retailers should be encouraged to step up and commit to action that ensures a level playing field. For example, it needs to look again at reformulation to ensure that it includes calorie reduction. I recently ate two digestives, one with the sugar removed. Both of course were delicious, but I was shocked to discover they both contained the same number of calories. Front of pack and menu labelling should be clear, and calories should be prominently displayed on alcoholic drinks.

Faced with relevant, accurate information people make better choices.

The depressing fact is that children have become even fatter during lockdown by snacking more and being in front of screens for much of the day.  Polling shows that parents want more help, advice and active support. They clearly need it, and doctors should feel more confident, not only in raising weight as an issue, but also with relevant nutritional information – which so many feel unqualified to give – and properly funded support services locally which so many areas still woefully lack.

If we wish to protect the NHS and to live a healthy life and old age, we should consider committing ourselves to the five rules of healthy living. A healthy weight, a healthy diet, regular exercise, no smoking and no (well, not too much) alcohol. I will. Will you take part too?

The author is a former Conservative MP and now a life peer. She was chair of the Centre for Social Justice “Off the Scales” working group on childhood obesity in England.