Daily asprin with milk 'cuts cancer risk'

A daily low dose aspirin pill taken with a glass of milk could be a simple way to avoid dying of cancer, UK research has suggested.

Taking aspirin for several years can cut the risk of death from a wide range of cancers by between a third and half, a landmark study has found.

Other evidence indicates that calcium in milk might enhance the drug's beneficial effects.

Scientists are stopping short of urging healthy people to take aspirin, which is known to increase the risk of internal bleeding.

But they say the new findings shift the risk-benefit balance in favour of aspirin, and could lead to a revision of medical guidelines.

Aspirin treatment to ward off cancer would probably be most effective between the ages of about 45 to 50, which is when most cancers start to develop, say the researchers.

The drug is already taken by millions of Britons at risk of heart attacks or strokes.

Regular low doses of aspirin help to prevent the changes that lead to narrowed arteries and blood clots. But in recent years evidence has started to emerge of much wider benefits from aspirin, leading to its description as a "miracle drug".

A previous study has shown that a 75 milligram dose of aspirin a day can reduce death rates from bowel cancer by more than a third.

Earlier this year US scientists reported that the same low dose cut the risk of men developing prostate cancer by up to 30%.

The new research, the most wide-ranging to date, involved picking out cancer trends from eight studies of aspirin's effects on arteries involving more than 25,000 patients.

Much of the cancer data had been "lost" in forgotten archives because it was not strictly relevant to the original focus of the trials.

But the findings are dramatic, showing a strong association between taking aspirin and a reduced risk of dying from a host of cancers.

They include diseases affecting the stomach and bowel, the oesophagus (gullet), the pancreas, the lungs, the prostate, the bladder and the kidneys.

During the trials, patients were taking at least 75 mg of aspirin every day for between four and eight years.

Significant benefits began to appear after five years of follow-up, with death rates for all cancers falling by 34% and for stomach and bowel cancers by 54%.

The benefit did not appear to increase with higher doses than 75 mg.

There was also evidence of a long-term effect spanning decades. After 20 years, the risk of death from all solid cancers remained 20% lower among patients who had previously taken aspirin. For stomach and bowel cancers, long-term death rates were 35% lower than they were for patients not given the drug.

The research is published today in an early online edition of The Lancet medical journal.

Study leader Professor Peter Rothwell, from Oxford University, said: "These results do not mean that all adults should immediately start taking aspirin, but they do demonstrate major new benefits that have not previously been factored into guideline recommendations.

"Previous guidelines have rightly cautioned that in healthy middle-aged people the small risk of bleeding on aspirin partly offsets the benefit from prevention of strokes and heart attacks, but the reductions in deaths due to several common cancers will now alter this balance for many people."

Epidemiologist Professor Peter Elwood, from the University of Cardiff, who has conducted his own extensive studies on aspirin, said taking the drug at night and with calcium seemed to enhance its effects.

He pointed out that milk was a good source of calcium, and also soothing to the stomach.

"We have suggested that in some of the new trials we should test taking aspirin with a glass of milk," he said.

Commenting on the new results, Prof Elwood said the risk of gastrointestinal bleeding in the average population was tiny, with around one in 2,000-3,000 people affected a year.

Aspirin doubled this very small risk, but there was no evidence that taking the drug increased death rates from internal bleeding.

People known to be vulnerable to bleeding in the gut could offset the risk with drugs called proton pump inhibitors, said Prof Elwood. Screening people for the stomach ulcer bug Helicobacter pylori could also reduce the risk of bleeding.

Speaking to journalists in London, both Prof Rothwell and Prof Elwood said they took aspirin every day. Prof Rothwell was persuaded by his own research on cancer, and Prof Elwood used the drug to reduce his risk of stroke.

Prof Rothwell cautioned that it was not yet known whether taking aspirin over a long period of time might have other adverse side effects besides bleeding.

The way aspirin combats cancer is unclear, but it is believed to boost mechanisms that either repair damaged DNA or cause potentially dangerous cells to commit suicide.

Aspirin is derived from salicylic acid, which is found in the bark and leaves of the willow tree and other plants.

In plants, the chemical is known to prevent infections and tumours.

"Some of the mechanisms in plants are similar to the mechanisms in humans," said Prof Elwood. "From the botanist's evidence it was predicted that there might be an affect on cancer in humans, and that is now what has happened."

Ed Yong, from the charity Cancer Research UK, said: "These promising results build on a large body of evidence suggesting that aspirin could reduce the risk of developing or dying from many different types of cancer.

"While earlier studies suggested that you only get benefits from taking high doses of aspirin, this new study tells us that even small doses reduce the risk of dying from cancer provided it is taken for at least five years.

"In addition to the effect on cancer death, aspirin can affect our health in other ways, such as reducing the risk of stroke but increasing the chances of bleeding from the gut. We await trials results expected next year to learn more about these different effects.

"We encourage anyone interested in taking aspirin on a regular basis to talk to their GP first."