Half of overweight Britons have cancelled plans because they feared they would not fit into seats or be comfortable while out, a study has found.

Research from online healthcare provider Numan suggests millions of UK adults could be abandoning major events such as weddings or flights over concerns about their size and comfort.

Around two-thirds of UK adults are classified as overweight or obese, meaning they have a body mass index (BMI) of more than 25, or 30 respectively. 

Numan's findings suggest the nation's so-called obesity epidemic is fuelling widespread 'seat anxiety'.

The survey of 3,000 British adults, named the Seat Anxiety Index, found that 34 per cent of overweight or obese participants dreaded being in the middle seat on a plane.

More than one in five said they disliked sitting on plastic chairs, commonly used at public events, while almost one in five said they felt uncomfortable using bar stools or window and aisle seats on a plane.

The middle seat is widely regarded as the least comfortable on a plane, as passengers are squeezed between two others with little room to move, compared to the extra legroom in aisle seats and window seats providing somewhere to lean.

One in three respondents also said they had cancelled or changed plans because of concerns about their size and their confidence in public spaces. 

This included physical activities such as going to the gym or playing sport - which are traditionally tougher for those carrying additional weight - but also major social gatherings.

Almost a quarter said they had avoided weddings, parties or restaurants because of concerns about seating and comfort. 

A worrying 17 per cent also reported delaying or avoiding visiting their GP because they were anxious about their size.

Obesity has been described by the Government as 'one of the most pressing challenges facing our health system'.  The crisis is estimated to cost the UK economy £74billion every year, including £11billion from the NHS. 

The survey also found that a third of respondents had paid, or considered paying, for upgrades such as extra legroom or additional space while travelling, at an average cost of £154 per person. 

Numan dubbed this a 'comfort tax' that, if proportionate to the UK population, would cost around £1.4billion.

Almost a third of respondents said they wished they could book a flight without worrying about comfort, while one in five said they wished they could go out for a meal without worrying about fitting into a seat.

Zoe Griffiths, vice president of behavioural medicine and registered dietitian at Numan, said: 'What struck us most in this data is what people say they've lost. It might not seem like big things - booking a flight, choosing a restaurant, going to a friend's wedding. Things many of us do without a second thought. 

'But for millions of people, those moments have become something to dread, and over time their world gets smaller because of it. That's what seat anxiety does.'

A fifth of respondents said they first noticed their 'seat anxiety' between the ages of 18 and 24.

Overall, women were more likely to feel unhappy or conscious about their appearance than men.

Meggy Goldberger, 28, from Cardiff, said she used to worry about travelling when she was obese.

Now, however, losing weight has transformed her confidence. 

She said: 'For years I dreaded flying because I knew I'd have to ask for a seatbelt extender – it was embarrassing, and it made me want to avoid it altogether. In the end, I stopped doing long-haul trips completely.

'But after taking control of my weight, that's changed. Last year was the first time in years I got on a plane without needing one – and now I actually look forward to travelling again.'

One of the biggest breakthroughs in tackling obesity in recent years has been the arrival of weight-loss jabs like Ozempic, Mounjaro and Wegovy - which is now available in a pill form.

Around 2.5million adults in the UK are thought to be using weight-loss jabs, but the arrival of the new tablet, which became available in Britain on Monday, has opened the door for people tackling obesity to have more options.

Ms Griffiths added: 'The good news is that the clinical tools for managing weight are better than they've ever been - and with oral treatments now available, injections are no longer the only way to start a medicated programme. 

'But the medication is only part of it. The confidence to stop checking seat sizes before you book, to stop arriving early for the right chair, to feel comfortable in public spaces - that doesn't come from a prescription or via weight loss. It comes from proper support over time. That's what Numan's programme is built around.'

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