Aspirin really is a wonder drug and here’s why you should consider taking it

As you would expect, a big part of my job as an A&E doctor is to prescribe medication and treatment.

But what you might not expect is that what I prescribe often changes.

That’s all down to the latest available evidence: And whether you should take aspirin is a case in point.

Until just a couple of months ago, I wouldn’t take a daily aspirin – nor did I advocate it for patients, unless they had specific risk factors such as a previous heart attack or following a stroke.

That was because of the risks of stomach bleeding – some studies show a daily dose increases the risk of bleeding by up to 50 per cent.

This sounds a lot but as only one in 1,000 patients gets a significant bleed, there needs to be 2,000 people on aspirin to cause one extra patient to suffer. And now there’s compelling new evidence, published recently in the journal Cancer, that has convinced me that the benefits of a daily 75mg ‘baby’ aspirin outweigh this risk for me, at least.

So I now take it every morning to try to improve my chances of living a longer, healthier life – and I think it’s something you might wish to consider, too (though make sure you read to the end of this piece, as there are caveats!).

Changing your mind as a doctor is not a sign of not knowing your stuff, but when new trustworthy results or theories emerge, our views must reflect this.

Indeed, in the last lecture I gave to our final-year medical students, I implored them to recognise that, while they will cease to be medical students, they should never stop being students of medicine: As 50 per cent of what we have taught them will turn out to be wrong – we just don’t know which 50 per cent that is yet.

Aspirin is one of the world’s best-known drugs – not just a painkiller but a wonderful clot-preventing medicine derived from the bark of the willow tree.

However, over the years working in A&E I’ve seen plenty of patients with awful stomach bleeds linked to taking aspirin: to my mind, this reinforced the idea that unless someone had a specific cardiovascular problem, such as a previous heart attack, the risks of taking aspirin were greater than the benefits of the clot-preventing properties.

Yet new evidence is emerging about aspirin’s benefits, suggesting it can help prevent some types of cancer, as well as increase your chance of survival if you do get the disease, by an amazing 20 per cent.

If you’re wondering why there hasn’t been much news about it, just remember aspirin is dirt cheap (costing just a couple of pennies per 75mg tablet), so there’s no incentive for drug companies to promote it.

That’s why the aspirin studies are often not the gold standard of expensive randomised, controlled studies (where treatment is compared against a placebo), but observational studies (where we analyse data from big groups of patients, some of who happen to be on aspirin).

So we need to look at these studies in detail. And that’s what a group of statisticians at Cardiff University have now done – publishing a massive analysis of 118 observational studies (pooling the results from over a million patients with 18 different types of cancer).

The review, in the British Journal of Cancer in November 2023, showed a 20 per cent reduction in deaths from cancer and any kind of illness throughout the studies in people taking aspirin compared with those not taking it.

And this is the important bit: The researchers wrote that “reasons against aspirin use include increased risk of a gastrointestinal bleed, though there appears to be no valid evidence that aspirin is responsible for fatal gastrointestinal bleeding.

“In conclusion, given the relative safety and favourable effects of aspirin, its use in cancer seems justified, and ethical implications of this simply that cancer patients should be informed of the evidence and encouraged to raise the topic with their healthcare team.”

We now also know why aspirin might help – thanks to the new study published in the journal Cancer, which I mentioned at the beginning.

Researchers in Italy had noted that colon cancer was less likely to metastasise in patients who regularly took aspirin. They investigated and found that aspirin increases the number of tumour-infiltrating lymphocytes (TILs) in the cancerous areas.

These TILs are specific parts of the immune system that help fight against cancer cells.

This wasn’t thanks to the anti-clotting properties of aspirin that we all know about – but through newly discovered mechanisms: Aspirin increased the amounts of a molecule called CD80 in cancer cells.

This attracts the TILs to the tumour.

In addition, aspirin increased the number of cytotoxic CD8+ T- cells, another potent tumour-fighting immune cell.

So aspirin is even more of a wonder drug than I realised. I have now changed the advice I give patients with cancer.

You must consult your doctor about this, but I believe the default position should be that if you have cancer, you should be on aspirin (75-100mg).

That is, unless there is a reason not to be (for instance, because you’re on a blood thinner for conditions such as the heart problem atrial fibrillation; and over the age of 70, there’s an increased risk of bleeding and some evidence that aspirin is not as effective and so the benefits versus the risks for older cancer patients is not as clear cut).

What about those with suspected cancer waiting for a diagnosis?

The long waiting lists mean that often the cancer has spread far more than it should when it is eventually identified. Aspirin can help slow the spread of cancer and my view is that the benefits of a 75mg dose are far greater than the risks and it’s something to ask your GP about if you or any loved ones are in this position.

The good news is that while drug companies aren’t interested in researching aspirin, the charity Cancer Care UK is leading the way, with a trial to see if it can help prevent cancer recurrence.

In the trial, called Add-Aspirin, patients with breast, colon, rectal, gastric and prostate cancers take a placebo, or one of two aspirin doses – 100mg and 300mg – for five years: These results will be published in the next few years.

If you are being treated for cancer, you can ask your oncologist if you can be recruited into the trial (it’s being run in hospitals across the UK, Ireland and India – in the UK, University Hospitals Coventry & Warwickshire is the biggest recruiter).

Just being in a trial – regardless of whether a patient is taking a placebo or active drug – boosts the chances of survival because of better follow-up and care.

The last question is this: Can aspirin prevent cancer in the first place?

While the studies are mostly observational, there is some evidence that aspirin reduces risks of bowel cancer especially if you have Lynch syndrome, a genetic condition that raises the risks of several types of cancer including bowel cancer.

However, a study from 2018 showed that if people start taking aspirin over the age of 70 it can increase the risks of cancer.

I plan to continue my new daily 75mg aspirin until I aged 70 – I’m at higher risk of bowel cancer because of a strong family history and I have the inflammatory gut condition, ulcerative colitis, which also raises the risk.

So do speak to your doctor about what’s appropriate for you – do not self-medicate.

And, ultimately, one of the best ways to improve your health is to keep knowledgeable and challenge us doctors; we may not know all the latest evidence and need you to question us, so we can give you the best possible, individualised advice we can.