Together we will beat cancer


You’ll probably have seen the media coverage today about aspirin, and whether it can help prevent cancer.

The news comes from a new scientific report by international experts (including some funded by Cancer Research UK), looking at all the available evidence about the over-the-counter drug’s pros and cons.

So what are they saying? And should you or I start taking it today? Well, the drug has risks as well as benefits, so our advice is: don’t take it without talking to your GP.

This graphic sums up the new data, and the unanswered questions:

Aspirin infographic

So why the uncertainty?

The story so far

Today’s headlines are the latest chapter in a story that’s been unfolding over the last few years. We’ve been following it since 2008, when we wrote this in-depth explainer about the state of the evidence.

In 2009, our researchers produced a new report, discussed here, concluding that more research was still needed.

Then, in 2010, a new analysis by researchers in Oxford suggested that the pros were beginning to outweigh the cons – although our experts still called for caution.

The last big announcement on the subject came in 2012, when the Oxford team published new data refining what was known about the balance of pros and cons. We discussed this extensively and, if you read one post on the subject, it’s this one, as it goes into detail about how the risks and benefits change over time.

So what’s new?

Ongoing studies

We’re funding several studies looking at aspirin in more detail, including:

  • CAPP3, to look at the best dose of aspirin to prevent  bowel cancer in people at high risk of the disease
  • AspECT, to look at whether it can prevent oesophageal cancer in patients with Barrett’s oesophagus, a condition that increases risk.
  • Add-Aspirin to look at whether aspirin can enhance the benefits of treatment in people already diagnosed with cancer.

And so to today’s news. The latest analysis, published in the Annals of Oncology, pulls together data from all available studies and clinical trials, and analyses where the balance lies more clearly than ever before.

It confirms that aspirin protects most strongly against bowel, stomach and oesophageal cancers, and also more weakly against lung, prostate and breast cancers.

It suggests that the benefits start building from age 50, so there’s little to gain from taking it below that age.

And it finds that if 1,000 people (500 men and 500 women) aged 60 take aspirin for ten years then – compared with 1,000 people who DIDN’T take aspirin – over the next 20 years you’d see:


Around 17 fewer deaths, including:

  • 16 fewer deaths from cancer overall
  • 1.4 fewer deaths from heart attacks


Between two and three extra death from:

  • 1.4 more lethal strokes
  • 0.3 more serious peptic ulcers
  • 0.65 more lethal gastric bleeds

Sounds positive overall, right? Well there are a few important omissions from the analysis that begin to muddy the waters.

It’s a bit more complicated than that

These risks and benefits aren’t evenly spread around the population. Some are at higher risk of side effects. Some people’s genetic make-up means they break down aspirin at different rates – some faster, some slower, than average. Some will have a lower risk of cancer without even taking the drug, so they won’t benefit as much (though they may still experience side effects). It’s an extremely complex, and still slightly murky,  picture.

So to be able to recommend aspirin to people in the full knowledge that the risks are being minimised, and the benefits maximised, doctors need to have a better idea of the following:

  • What age should people start, and stop, taking aspirin?
  • What dose should they take?
  • What are the factors that should rule someone out from taking aspirin, and how should we test for them?

At the moment, frustratingly, there’s no clear, definitive answer to these questions. And until there are, we’re discouraging people from stocking up on their own supplies of aspirin without seeking medical advice first.

So if you’re worried about your risk of cancer, and want to do something about it, your first port of call should always be your GP.




m white November 27, 2014

There needs to be a lot more research in to this we will get there soon.

M. Dawson October 9, 2014

Very interesting email leaving us waiting for more information when it has been proven. Thank you.

Gladys Edmonds September 27, 2014

Your article was concise,nice and clear. Thank you.

mark scobby September 26, 2014

my dad took aspirin for over 38 years he died age 84 not of cancer but of bad lungs due to working in the pub and club trade i myself have taken aspirin for over 15 years until my doctor said stop taking them for no good reason

mrs june meier September 10, 2014

if aspirin helps to lower the risk of cancer then it could only be a good thing.I had my breast removed three and half years ago from cancer and have another year and half before I get the all clear.

Nick Peel September 9, 2014

Hi Roman, thanks for your question. The trials looking at the health effects of aspirin used low doses of aspirin every day for at least 5 years, and they looked at aspirin alone, rather than in any other combination. This isn’t the same as the use of aspirin or aspirin-containing drugs to relieve a headache or when taken in any other pattern, and we wouldn’t be able to make any comments about your situation I’m afraid. We would recommend talking to your doctor about the medication you are taking as they may be able to offer some advice.

Nick, Cancer Research UK