The cancer risk in your 'healthy' glass of fruit juice which has so much sugar it could bring on tumoursBy Sophie Borland
Last updated at 10:32 AM on 26th September 2011
But a glass of juice might not be as beneficial as you think – and could even be harmful.
Scientists claim fruit juice contains so much sugar it actually increases the risk of certain cancers, rather than preventing them.
In fact, by the time the drink has been processed and packaged, many of the ingredients in fruit that protect against tumours have been lost, they say.
Australian researchers had sought to establish how effective different fruits, vegetables and juices were at preventing the development of bowel cancer.
They examined the diets of 2,200 adults, who filled in a questionnaire detailing their daily eating habits. The team then tracked the participants for two years to see how many of them developed the disease.
Unsurprisingly they found that eating apples, sprouts, cauliflower or broccoli on a daily basis all reduced the likelihood.
However, those who consumed lots of fruit juice had a higher risk.
The research, published in the Journal of the American Dietetic Association, found that those drinking more than three glasses a day were more likely to develop rectal cancer, a form of bowel cancer.
Scientists believe the high sugar content in juice may trigger certain tumours.
The Perth team also said that many things found in fruit which help protect against bowel cancer – including fibre, vitamin C and chemicals known as antioxidants – are lost during the juice’s processing.
For years, Department of Health guidelines have advised the public to eat five portions of fruit and veg a day, which can include a glass of juice.
But British researchers claimed earlier this year that fruit juice contains too much sugar to be counted as one of the five. The scientists, of Bangor University, Wales, said people would be better off eating prunes or other dried fruit, as even freshly-squeezed juice contains as much as five teaspoons of sugar per glass.
However, other experts suggest that people shouldn’t shun fruit juice completely, as it is still healthier than other drinks.
Nell Barrie, of Cancer Research UK, said of the latest research: ‘This isn’t a large study, and it doesn’t give us clear answers about whether different fruits and vegetables affect the risk of cancer in parts of the bowel.
‘It’s very tricky to tease apart the effects of a person’s diet on their risk of bowel cancer, but reliable evidence shows that eating lots of red and processed meats increases the risk, while eating plenty of high-fibre foods can reduce the risk.
‘Many fruits and vegetables are a good source of fibre, and eating a diet that’s high in fruits and vegetables could reduce the risk of other types of cancer as well – so it’s a good idea to get plenty of them in your diet.’