A poll of 2,000 adults found more than a fifth (23 per cent) weigh more now compared to a year ago, while 58 per cent of these believe the financial crisis has contributed to their weight gain.
And 31 per cent prioritise the cost of food over how healthy it is.
In fact, 18 per cent said they were making more unhealthy dietary swaps now than they did before the cost of living crisis began.
Since the end of 2021, 80 per cent adults said they have concerns about rising food prices.
Dr. Jacquie Lavin, a special advisor on the science of weight management at Slimming World, said: “It’s well documented the cost-of-living crisis is having a big impact on people’s buying habits.
“This research shows that 31 per cent of people are prioritising the cost of food over how healthy it is.
"Without the right support, there is a very real possibility that the financial crisis could make it even more difficult for people to manage their weight and health.”
The survey found of those who have gained weight, 38 per cent put this down to comfort eating or eating more fast food.
The impact of the cost of living has also led to 30 per cent saying they have less motivation to exercise, and 20 per cent using alcohol to deal with the stress of the situation.
Just under a fifth (19 per cent) have changed where they do their food shopping as a result of the increased cost of living.
It’s not only physical health which has been affected in recent months, as 46 per cent confess their mental wellbeing has also taken a hit.
And 47 per cent feel the Government is not doing enough to help people eat a healthy diet, while the nation’s finances are stretched.
The survey, carried out by OnePoll, found 68 per cent reckon it’s easier to be healthy when you have a lot of money.
Dr. Lavin, for Slimming World, said: “Getting practical advice and tangible tried-and-tested tips can be especially valuable when you’re finding it more difficult to eat healthily and lose weight or stay on track.
“The research showed some 38 per cent of UK adults don’t feel they’ve picked up any advice, for example from friends and family, social media, supermarkets, or colleagues.
“This shows how being part of a group, where you’re facing the same challenges together and helping each other to stay motivated makes a real difference. It’s even better when this support is in a warm, friendly community particularly during such difficult times.”
Join our commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies