Mouth cancer rates have risen by more than two thirds over the last 20 years due to unhealthy lifestyles.
Data from Cancer Research UK shows the disease has risen 68 per cent, with the rise affecting men and women of all ages.
Poor diets, drinking, smoking and the spread of infections are to blame.
Some 11,400 people are diagnosed with oral cancer in the UK each year – including cancer of the lips, tongue, mouth, tonsils and the middle part of the throat. The disease kills 2,300.
Nine out of every ten cases are linked to unhealthy lifestyles.
Mouth cancer rates have risen by more than two thirds thanks to people having diets low in fruit and vegetables, smoking, and drinking
After taking into account Britain’s population growth, experts calculated there were eight cases of mouth cancer per 100,000 people from 1993 to 1995, rising to 13 cases per 100,000 people between 2012 and 2014.
Smoking rates – which cause 65 per cent of oral cancer cases – have dropped dramatically in recent years.
But scientists think oral cancer is still rising because of a ‘lag effect’ – with the thousands of people who started smoking 50 or 60 years ago only now seeing an effect.
Rising drinking rates, particularly among women, may also be behind the trend, along with diets low in fruit and vegetables.
Infection with the human papilloma virus – known as HPV – causes about 13 per cent of cases.
Jessica Kirby, Cancer Research UK’s senior health information manager, said: ‘There are likely to be several factors behind the continued rise in oral cancer in the UK. Two of the risk factors linked to the largest number of cases are smoking and drinking.
‘Cancer incidence rates today are often linked to what people were doing years or even decades ago – when smoking rates and the amount of alcohol people were drinking were rising.’
She added: ‘It’s worrying that oral cancer has become more common. It’s important to get to know your body and what’s normal for you, to help spot the disease as early as possible.
‘An ulcer or sore in your mouth or tongue that won’t go away, a lump on your lip or in your mouth, a red or red and white patch in your mouth or an unexplained lump in your neck are all things to look out for.
People who started smoking 50 or 60 years ago only now seeing an effect, scientists say
‘Healthy lifestyles can help reduce the risk of developing the disease in the first place.
‘Not smoking, drinking less alcohol and eating plenty of fruit and vegetables can all help to cut our risk of mouth cancer.’
For men under 50, the rate has jumped by 67 per cent.
Twenty years ago there were around 340 cases per year in this age group, rising to around 640 now.
For men aged 50 and over, rates have increased by 59 per cent. There were around 2,100 cases a year – now there are 4,400.
While mouth cancer is more common in men, women are also affected and have seen a 71 per cent rise in rates over the last 20 years.
Russ Ladwa of the British Dental Association said: ‘Oral cancer is on the rise, yet half of adults are not seeing a dentist.
‘Early detection is key, and a check-up can mean the difference between a 90 per cent and 50 per cent survival rate.’