Of the 50,000 people 50 and over quizzed by SunLife, 85% who had already retired said they did so too early, rising to 88% of those who are now over 70.

On average, those who are retired or semi-retired think they quit their job two and a half years too early. Those aged 70+ think they retired three years too early.

Less than 10% think they retired too late and just 5% said they got the timing right.

The research also shows a fifth of retirees continue to earn money by starting their own business, selling items on ebay, renting out property, private tutoring, exam invigilating and working for the elections office.

Others are using their skills to make crafts and cakes to sell, while some said they model for art classes.

Ian Atkinson, marketing director at SunLife, said: “Our research shows that people aged 50 and over feel 10 years younger mentally and almost four years younger physically, so, far from being ‘over the hill’, people in their 50s, 60s and 70s are feeling fit, healthy and sharp, which could explain why so many feel they gave up work too early and why so many are starting new careers.”