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Talk to your GP first

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.



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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

Roman Kirsch September 9, 2014

The main agent inside Aspirin tablets is acetylsalicyl acid, I guess. I regularly take Acifein tablets, which contain also Paracetamolum (the same dose – 250 mg). So does Acifein have the same effect against cancer? Thanks for your reply!

J Ballantyne September 7, 2014

I have been taking daily asprin, 75mg daily since 2007 as a precautionary measure following diagnoses of Left Bundle Branch Block. I was confirmed to have seminoma testicular cancer in 2011. In my case asprin was not effective against the particular type of cancer that developed in me.
As some might say; it could have been worse?

David Armer September 6, 2014

I have been taking aspirin now for more than 30 years. I started after a friend of mine had a massive heart attack aged 40 in 1980. I have had no problems at all, but I have always used soluble aspirin and always after food. I had bypass surgery in 1995 but did not have a heart attack beforehand, and if I suffered angina 2 aspirin always relieved it. Not everyone can take aspirin – my wife included – but if you use it as I do you reduce the chance of stomach problems. My sister took the coated ones, but they caused problems in the small intestine.

Sue Gregory September 6, 2014

Very interesting. Has any work been done on the effects of aspirin substitutes? I am taking Clopidogrel which my pharmacist tells me fulfills the role of aspirin but works in a different way.

K Cooke September 6, 2014

I’ve followed the Aspirin research closely for some time and because I lost my mum relatively young (55 yrs old) to bowel cancer I’ve been taking 75 mg aspirin daily for the last 3 yrs (I’m now 43). I consulted my GP first and she was happy for me to take them and I’m also on regular colonoscopy screening. I’m a nurse and I will hopefully recognise side effects, should the arise, but so far I have had none. I will definitely carry on taking aspirin.

Jean Myhill September 6, 2014

my then GP recommended all his patients over 40 took 75mg of soluble aspirin, and reduced eating ham or bacon, in fact any preserved meats to once a week. I have followed this advice for the last 30years with no ill effects

D John September 5, 2014

Very interesting report. I had a stroke 7 years ago when i was 50. I have been prescribed aspirin as part of my preventative medication. To see aspirin fall into the risk catagory for causing strokes has caused made me wonder if this was the correct decision

christine duke September 5, 2014

very interesting news

Liz Steel September 5, 2014

A few years ago my brother was taking prescribed low dose aspirin. Over a year or so he became very tired and weak. He had been bleeding internally due to the aspirin and his haemoglobin was so low that he almost died.None of us in the family take aspirin as a result. I do think people should be made aware of this. Liz Steel

John Turner September 5, 2014

Seems a fair and balanced analysis, which is needed, thank you.

I’ve been taking 75mg daily for 4 years now, since turning 70. Will continue.

Terence Chancellor September 5, 2014

I had a heart attack in 1994 and began taking soluble aspring; 250 reducing to 75mg. I did not stop be having bowel cancer in 2009 which an operation cured and all has been well since. Curious. I still continue to take 75mg daily and have no side effect at the age of 84

Terry September 5, 2014

I have been taking soluble aspirin for over 22 years following a heart attack. To date I am not aware of any side effects.

Angela Fullerton September 5, 2014

I took aspirin until atrial fibrillation and now have warferin. My aspirin was prescribed after I had cancer.

James Sumner September 5, 2014

Both my parents died with cancer so I started taking one 75mg soluble asprin per day when I was 50. I am 85 now and as far as I know free from cancer and side effects.Fingers crossed.

Cliff September 5, 2014

I read of these early reports, did a little bit of my own research & decided that I would start to take asprin daily. I (& my wife) have been taking 75mg enteric coated asprin a day for the last six years with no noticable downside. I did not consult my doctor about it as they clearly could not give me a do or don’t. As we read above there is no definitive yes or no I just feel that the possible pros outweigh the possible cons & for 85p a month why not. So I plan to continue indefinitely. (I’m 60)

Ken Hills September 5, 2014

I decided to take one aspirin alternate days . That is half of my GP’s presvription. He knows this and doesn’t dissent.. I don’t have any idea what is best, so I’ll watch for the next reliable research results.

sheila leatham September 5, 2014

we have bowel cancer in our family which i have the gene several have died young plus my mother had several strokes i started taking asprin at 35 and have taken one 75mg since now 68 and keeping fingers crossed and toes i am ok all though rather large

Tony Pink September 5, 2014

I have always taken Aspirin when required. It is the only over the counter drug that can stop my headaches. I have tried all the other types of drug and they are of no use, so I am a great believer in Aspirin. I know off the stomach problems that use of Aspirin can cause but in my case the benefits out-way the risks. The research seems to show that this is the case when it comes to Cancer prevention.

Tess September 5, 2014

Thank you. That’s a very honest and balanced explanation. I personally have doubts because my dad took a quarter of an aspirin every day for around 30 years and it was strongly suspected that the constant regular use gave rise to the liver tumour that killed him, therefore I’m not a big fan. However, I’m sure there ARE benefits for some people and I hope the research will give many people a better chance.

Sue Fricker September 5, 2014

And if the experts don’t really know then the GP will be no better placed to advise one way or the other. So until that point is reached ” I’m out”

Michael Andrew Scott September 5, 2014

Your GP should be consulted before taking regular doses of a Aspirin.Family history would be discussed . My Doctor
always advises me to get in touch with him ASAP with regards to any
changes in by bodily functions and is always discussed whenever I attend the practice

James September 5, 2014

thank you for advising the facts , from a neutral standpoint

Manohar V. Rakhe September 5, 2014

Sir, I had a heart attack in 1988 & a second one in 1993. I have been taking 75 mg dose of dispersible aspirin, daily since 1988 till to date. I was 43 at the time of my first heart attack. After 1993, I have not had any heart problem at all. I have had regular screening for bowel cancer after I turned 60. There is no sign of bowel cancer. Earlier this year I had a complete check up for lung cancer. None was detected. I have displayed no discernible symptoms of any kind of ulcers. So, personally, I would be quite happy to go on taking 75 mg dose of aspirin daily or until my GP advises me to discontinue it.