Up to 28 million Britons are living with chronic pain, new estimates suggest.
Problems such as low back pain or osteoarthritis affect between 35% and 51% of British adults, according to a new study.
Overall experts have estimated that 43% of adults have pain that has lasted for more than three months.
And they warned that the figure is only likely to rise with an ageing population.
Their study, published in the journal BMJ Open, saw experts examine data from 19 studies including almost 140,000 UK adults.
They found that chronic pain prevalence increased with age, with around one in seven adults under 25 reporting chronic pain compared to almost two-thirds of people over 75.
The authors wrote: "Chronic pain affects between one-third and one-half of the population of the UK, corresponding to just under 28 million adults, based on data from the best available published studies.
"Chronic pain prevalence rises steadily with increasing age, affecting up to 62% of the population over the age of 75, suggesting that the burden of chronic pain may increase further still, in line with an ageing population."
They also found that around eight million people suffer moderate to severely disabling chronic pain.
Women were more likely than men to be affected by chronic pain, they added.
Olivia Belle, director of external affairs at Arthritis Research UK, said: "This is an important study, which starkly shows the devastating impact that chronic pain is having on people in the UK.
"As our population continues to age and obesity rates rise, we are only going to see these numbers grow.
"And although we may not be able to see it, living in pain, day in and day out, can have a devastating impact on people's lives, affecting their independence, mobility and ability to stay in work.
"There is also, unsurprisingly, a direct link between chronic pain and depression. If we are going to address this growing need, we need better pain management and better treatments to relieve pain."