Tom Whipple, Science Editor
Gerry Gajadharsingh writes:
“Sadly, the title does not reflect the research, which is about sugar feeding tumour growth not drinking fizzy drinks. I put sugar in brackets. It focuses on colorectal cancer in mice backing up other work linking sugar and bowel cancer. It was done in response to a doubling in colon cancer in your people (under 35) in the USA, I suspect UK figures are not that far behind.
The amount fed to the mice was equivalent to I can of cola a day for humans. It doubled the growth rate of the cancer.
The lead researcher says “I think the scary thing is it doesn’t matter where sugar comes from in liquid form. My advice is eat an apple, not apple juice.”
The other cancer that is increasing is pancreatic cancer, involved in carbohydrate regulation. Interesting fact is that the tumour marker for pancreatic cancer is CA 19-9, (CA means carbohydrate antigen)
Hmm I wonder if there is a connection, let’s see what research says in a few years.
A high sugar environment, systemic (sometimes silent) inflammation, altered pH and perhaps compromised O2 delivery on a cellular level, may well be mixing with our genetic predisposition and environmental factors and increasing cancer risk.”
Fizzy drinks could be exacerbating the growth of intestinal tumours, according to a study in mice which found that the cancers “feed” on sugary liquid.
The research, prompted by evidence that people may be contracting colorectal cancers earlier than they used to, showed that intestinal tumours use glucose and fructose to accelerate their metabolism and boost their growth.
The scientists said that this could explain apparent correlations found in other work that showed a tentative link between sugary drinks and bowel cancer, which is the fourth most common cancer in the UK, killing 16,000 people a year and carrying a lifetime risk of about 4 per cent.
However, scientists warned that this mechanism, reported in Science, had been demonstrated in mice genetically engineered to be prone to cancer, and may not translate into humans.
Lewis Cantley, from Weill Cornell Medicine in New York City, said the work was a response to cases of colorectal cancer among young people. Although still extremely rare, he said, the incidence had doubled in the US among people under 35. “It’s been a mystery,” he said. “What are we doing differently?”
Hypothesising that this rise could be due to sugar intake, which increases insulin production and could in turn aid cancer growth, he and his colleagues fed high-fructose corn syrup to mice that were prone to intestinal cancer. The level was equivalent to less than one can of cola per day for a human.
Corn syrup, a mix of glucose and fructose, is used in the US to sweeten drinks. Cane sugar, more common in the UK, has fructose and glucose in similar proportions.
To Professor Cantley’s surprise, the insulin theory was wrong. “The tumour was directly eating the sugar,” he said. The scientists found that the cancer was using fructose and glucose together to more than double its growth rate. “The tumour required both sugars to grow,” he said.
Although there was no evidence that the sugar caused cancer to appear, many people have slow-growing cancers that they are unaware of. “Probably there are micropolyps on everyone’s intestine by the time they are 45,” Professor Cantley said. “If they grow slowly they may take 20 to 25 years to be picked up. If they grow very fast, it will be a problem far sooner. These polyps are exposed to the intestine. If you ate an apple, all the sugar would leech out by the time it reaches it. But anything you drink gets there quickly.
“I think the scary thing is it doesn’t matter where sugar comes from in liquid form. My advice is eat an apple, not apple juice.”
Michael Skilton from the University of Sydney, who was not involved in the study, was impressed by how the research had teased out apparent mechanisms underlying the tumour growth, but said it remained to be shown that the findings applied to humans. Even if they did not, he said, it was a good idea to cut back on sugary drinks.
“High-fructose corn syrup and cane sugar are both strongly linked with obesity, which itself is a strong risk factor for several cancers,” he said. “Irrespective of whether these sweeteners are having a direct effect on tumour development and growth, people wishing to reduce their likelihood of developing cancer should limit their intake.”
What’s in your bottle?
Sugar content, per 100ml
Cloudy apple juice 13.0g
Yop strawberry 11.0g
Schweppes Indian Tonic Water 5.1g
R Whites Lemonade 2.4g