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The close to 40% reduction (for several types of cancer) is pretty dramatic. And the breadth of the study (600k patients) seems reasonable.

Is this really big news, or some skewed view of a study?

> Is this really big news, or some skewed view of a study?

Observational studies about the so-called benefits of aspirin come several times a year. But hey, why don't they put it in actual clinical trial instead, if they are SO confident it works so well?

Clinical trials for cancer prevention would mean 20-50 years no? That's a pretty big undertaking.

I mean you would need a control group and a real one, and then just wait ... for a long time

no. Cancer trials take a few years. You don't need to wait for everybody to get cancer, because small numbers of people get cancer stochastically every year.
Cancer is not rare enough to make it impossible to test in controlled populations. And actual cancer drug trials can recruit several thousands of patients routinely and will show clear survival benefits on that kind of base size if the effect is large enough.
Not only that, but you would need trust in both groups to keep doing what they should for this study. For 20 years, that's really long.
I have no knowledge of the field, but I'm guessing that zero profit potential for this therapy might have something to do with it.

Hell, you can make aspirin in your kitchen.

> I have no knowledge of the field, but I'm guessing that zero profit potential for this therapy might have something to do with it.

It could be a trial financed by public institutions/governments, since it may have good impact on the overall health system if you can drastically reduce/delay cancer rates... (plus aspirin is dirty cheap to make compared to expensive cancer care once a cancer is found). Unless such institutions have a clear incentive to let people die earlier...

Anyway, my point is, even if for-profit organizations won't do it, public organizations should be able to get funding if it makes sense for the public good.

That might happen now that this study has been published!

Let's not forget that medical science is ongoing - the idea that aspirin could prevent heart attacks probably seemed like quackery at one point too.

If it’s in a UK newspaper you can safely take it with a pinch of salt. They have an unhealthy obsession with declaring various substances as causing or curing cancer
After mulling on it, I wonder if the population that happens to take aspirin daily is heavily skewed towards "I just had a heart attack".

That would imply either or both of:

- Drastic changes in lifestyle (quit smoking, better diet, more exercise, etc) that might also reduce cancer occurrence

- More likely to die of a heart issue before any cancer develops.

And more likely to be checked by a physician on a regular basis.
The telegraph doesn't have a good record of reporting health press releases.

Maybe this article will eventually find its way to behind the headlines.

https://www.nhs.uk/news/cancer/

So why don't we all take acetylic acid? Because as all blood diluents it can have dramatic consequences - a hemorrhage. Also, if you have an accident, things can get quite complicated. That's why a doctor will prescribe acetylic acid only if the benefits outweigh the risks - which is not always easy to assess.
It's become common to prescribe daily aspirin for older people afaik
I take aspirin on a regular cadence and have tinnitus as a fun side effect. This is actually quite common [1] but you won't hear a doctor giving that warning. No pun intended.

[1] http://www.arthritis.org/living-with-arthritis/treatments/me...

Some commmon drugs cause hearing loss (ototoxic), but this is rarely mentioned by doctors. I guess hearing isn't considered as important as sight.
In my case, hearing loss is less of a problem than closing off of the arteries. I'm going as far to experiment with off-label 2-hydroxypropyl-Beta-Cyclodextrin which can also cause hearing loss. My only point is that people should not take aspirin unless they have a medical need to do so that outweighs the risk of hearing loss.
But what dosage are you on? Say I use a pill cutter and take half a baby aspirin a day (40-50mg). Do I risk hearing loss?
There are papers on PubMed that can point you in the right direction on that; but I just wanted to point out that if you get a DNA test (23andme and others), you get tested for a mutation that makes stomach bleeding more likely if you take aspirin. So the answer to both may be "it depends on your genes."
Aspirin is known to cause temporary mild tinnitus at high doses but as far as I'm aware it has not been solidly proven to cause permanent tinnitus.
If those numbers are real (still looking for the link) I’m assuming that small dosage could have dramatic results.

Combine that with a drop in accidents and bleeding thanks to self-driving cars and you might have recommended micro-dosing.

What kind of accident do you mean?
Any trauma with bleeding. It thins the blood, making it especially hard to stop bleeding.
Please post something more substantial. No links to the actual papers, no proper summary of how the data was generated (who they recruited, etc...), in other words it's blogspam at best.
I take aspirin protect, made by bayer. Grandad and dad had heart issues, so my dr started me a while ago on it as to curb the risks.

An aspirin a day will also make your nose bleed after a few weeks. Albeit not profusely but if you blow your nose, you will see blood.

take one every 3rd say. Unless its a very small dosage with delayed release.

Aspirin should not be messed with, make sure you eat before you take a pill, or itll tear a hole in your stomach. Ive made that mistake once a decade ago.

Please consult your doctor before grabbing off-the-counter aspirin.

You can get tiny dosage pills, I use 75mg ones -- easily available at the supermarket in the uk. No node bleeding with that, even if you do risk bleeding a bit more than usual if you cut yourself.... Small price to pay for the 'feature' of thinning the blood, I suppose?
I used to take those (for over a year), but my nose bleeds were difficult to stop and when I got an aneurysm at the bottom of my mouth I thought what if this happens in my brain? So I stopped taking the Aspirin.
Ouch sorry to hear that. And youre right, the thought of aspirin exacdrbating a brain aneurism are also something i think about too
>itll tear a hole in your stomach. Ive made that mistake once a decade ago.

I know somone suffering from this mistake right now. Did this resolve on its own for you?

I made sure i avoided spicy and acidic food (read also anything sweet. Sweet potato/yams is ok) st, even "well seasoned" stuff. Herbs and abit of salt were ok amd even beneficial. did moderate sports activities, but that hurt like hell. Walking 30 minutes a day should be enough. Keep hydrated, make sure the food is soft - avoid processed foods and fizzy drinks and coffee at al cost. Sugarless herbal tee is all i drank in the morning, two full cups.

Drank small doeses of anti acids before bed.

I did a gastroscopy a year after that and it had healed.

Smoking can exacerbate the condition and i quit for the duration.

Mind you i was young at the time. The body heals itsself you just have to get out of the way.

Im sorry for your friend, i still remeber the pain. Walking felt like being contonuisly stabbed in the stomach every 3rd step.

Edited with more info

thank you. passed this info on.
The comment below me is also very helpful - joghurt is really good for it. Esp goat joghurt, but its taste is not too good

I remember reading something about dental hygine too. Acidic mouth -> bacteria -> somehow effects the stomach too as we swallow our salyva

Is there any risk of the thinner blood leaving you predisposed to complications in the event of an unrelated traumatic injury?

..analagous to how Amber died in season 4 of House?

Yes, that's the main reason aspirin isn't recommended more widely. (Stomach and liver harm are the other big reasons.)

It's not necessarily external trauma, but major bleeding events, especially internal, are more prevalent and severe on aspirin. The NNT/NNH breakdown suggests that heart attack and stroke prevention narrowly beats out increased bleeding, but it's not unambiguous.

(Normally you handle this by recommended preventatives to people at high risk so you get a better ratio. This sometimes works with aspirin, but older people are often at high risk for stroke and bleeding, so the problem sticks around.)

I don't know how cancer prevention factors in - it might push aspirin into clear net-positive territory - but regardless you're right about blood thinners creating trauma risk.

> Yes, that's the main reason aspirin isn't recommended more widely. (Stomach and liver harm are the other big reasons.)

Liver is paracetamol — aside from Reye Syndrome[0] — aspirin is metabolised via the kidneys and I believe even overdoses does not overload the kidneys[1], however aspirin inhibits excretion of uric acid which is why it's contra-indicated to people suffering from gout or kidney diseases.

[0] https://en.wikipedia.org/wiki/Reye_syndrome linked to both aspirin and liver toxicity

[1] in fact one part of aspirin overdose protocol is urinary alkalinization: increasing urinary pH from ~5 to ~8 increases renal elimination of salicylate by 10~20x

Ah, thanks. I knew I'd heard of aspirin-liver related crises, but I hadn't realized Reye Syndrome happened outside of normal metabolism!
>Are more prevelent

As for the internal bleeding risks.

https://books.google.com/books?id=j-XQ1UqLdAQC&pg=PT41&lpg=P...

"These results translate into an absolute rate increase with aspirin above placebo (the incidence of cases of major GI bleeding attributable to low-dose aspirin) of 0.12% per year (95% CI: 0.070.19% per year).[20] Based on this value, 833 patients (95% CI: 5261429 patients) would need to be treated with low-dose aspirin instead of placebo to cause one major GI bleeding episode during a 1-year period (i.e. the NNH is 833)"

> it might push aspirin into clear net-positive territory

It's pretty clearly in the net positive territory. Reduces sunburn, reduces obesity, can stop a heart attack or stroke immediately, cures hangovers, and reduces cancers.

Oh yes. You /will bleed/ more.

Has no effect on healing as far as i can see, and i cut myself now and then regularly. (i cook alot) but i heal quickly. Now if i ever cut into a large blood vessel... Yeah ill be in trouble.

If you consider doing dental work though, please let your dentist know.

Hospitals ask about aspirin if they want to do surgery.

> An aspirin a day will also make your nose bleed after a few weeks. Albeit not profusely but if you blow your nose, you will see blood.

Should depend on dose and physiology: for low doses (below ~4g) the half life of aspirin is 2 to 4.5h depending on the person. If you saturate the metabolic pathway however the half-life shoots up to 15~30h.

> take one every 3rd say. Unless its a very small dosage with delayed release.

The study was done with 80mg aspirin daily (sometimes called "baby" aspirin). Standard adult dose around here is 500mg.

My experience is with 100mg delayed release over 10 years.

And jesus, 500mg? Holy crap

As far as I know, the over the counter 500mg dose is sold over here as a painkiller, it's certainly not meant for long term preventative use.
Sounds pretty damn irresponsible to me.

Im glad my dr is a sane one. I dont see anyone needing high doses unless your dealing with a mayocardial infarction where high doses of aspirin are administired to prevent damage to the heart.

> the over the counter 500mg dose is sold over here as a painkiller, it's certainly not meant for long term preventative use.

Most def', but if you ask for aspirin without specifying any further that's what you get (that's what I'm given every time anyway). I'm not sure you can even get 75~80mg, 100mg seems to be the lowest dose available (for long-term use after infarction & stuff, and for toddlers).

In the US and UK one can get ~80mg (75, 81) OTC, at any drug store / chemist.
The story doesn't end there: aspirin is an irreversible inhibitor of a platelet aggregation pathway.

So its effects last longer than the circulation of free aspirin in the bloodstream.

Its effects last until the enzymes in that pathway get regenerated. The enzymes' turnover is over a period of several days.

Thank you. I can't believe how often this fact is ignored in public discussions.
You need to clarify. Are you taking a low-dose aspirin? I've been taking an 85mg one once a day for 5+ years. Never had a single problem you outline.
Same here. I was prescribed low dosage Bayer (81mg) four years ago due to heart issues. Never had a problem with bleeding or clotting for that matter.
I was prescribed omeprazole to protect the stomach along with my meds 75mg aspirin included.
You may want to take a calcium citrate supplement too, as long term omeprazole use has been linked to calcium depletion.
Everybody is different, of course. I have been taking an aspirin a day for more than a decade and do not routinely get nose bleeds. If I'm at a high elevation and it is cold, I get a nose bleed. But other than that I do not.
NSAIDs greatly increase your chances of ulcers and gastritis even if you take them on a full stomach.
To elaborate, they don't damage your stomach via contact, they inhibit COX which is an enzyme that contributes to gastric mucosal protection and regeneration.

So it doesn't matter whether you eat with them or not, largely, unless what you're eating with them is an antacid or proton pump inhibitor.

Oh wow, thank you, that's pretty interrsting
But wait, there's more! There are at least two COX pathways; COX-1 is involved in protection of stomach lining, COX-2 is responsible, in part, for pain signalling.

Aspirin inhibits both pathways. Other NSAIDs do the same, although they typically have less of an effect on COX-1.

There is something on the unnoficial market which may inhibit only COX-2, a sort of holy grail in the last few decades of medicine: kratom[0].

0.https://www.ncbi.nlm.nih.gov/pubmed/21513785

Damnit im trying to finish a project! Now i have to read that link :P
Ah, but interestingly, inhibiting either cox pathway independently doesn't damage mucosa. you have to inhibit both, simultaneously, and the limiting factor is the one that is the least inhibited. So it's not just "COX-2 good, COX-1 bad", it's actually "Either pathway is fine to inhibit selectively as long as you don't inhibit both"
Anecdotally, Kratom use can also lead to long, opiate like withdrawls (weeks of hyperalgesia, no fun). Other short term opiate like side effects like nausea are common as well. I would definitely recommend against self-experimentation unless you are prepared for lengthy withdrawl symptoms.

Hopefully more research can be done into its constituent chemicals before it is banned in the US. The DEA already tried, and its illegal in several states.

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I'm wondering what other HN users think of the merits of reducing the omega-6 to omega-3 ratio as an alternative to aspirin (in certain cases).

Aspirin works by irreversibly inactivating the COX enzyme [0], which is involved the Arachidonic Acid Cascade [1], which at the same time is affected by the aforementioned essential fatty acid ratio.

COX enzyme inactivation supresses the production of thromboxanes, which explains your bleeding.

[0] https://en.wikipedia.org/wiki/Mechanism_of_action_of_aspirin [1] https://en.wikipedia.org/wiki/Essential_fatty_acid_interacti...

Edit: Added last parragraph

I think it's better to reduce total PUFA consumption, than to dilute out omega-6's with omega-3's. Both types of oils are unstable at body temperature.

Human operating temperature is much closer to a cow (or coconut) than to an artic fish.

> Human operating temperature is much closer to a cow (or coconut) than to an artic fish.

Why is that relevant?

Im infering that the chemistry of said oils vary enough between the two temps to matter

Its the implication

What about non digestion-system intake ? just curious

- sublingual - intramuscular - anal

I don't know for aspirin but the method of intake may not matter: e.g. non steroidal anti-inflammatory drugs such as ketoprofen induce aggression of the gastrointestinal system in ways unrelated to ingestion, hence why on the short run you're encouraged to eat (which will somehow dilute the natural gastric acid) right after having taking the medication (which takes ~0.5hrs to reach peak blood concentration[1]but falls gradually afterwards), or on the long run you may be encouraged to take proton pump[0] inhibitors, which come with their own side effects. (Disclaimer: not a medic, only remotely a chemist, but had to deal with this for extended durations).

It's an awfully complex equation of chemical actions and risks vs benefits. Be safe, nothing about this is magic and can have serious consequences.

[0]: https://en.wikipedia.org/wiki/Proton_pump#In_humans

[1]: four doses of ketoprofen: https://www.drugs.com/pro/images/c2c99853-1268-4998-a44b-2bf... (from https://www.drugs.com/pro/ketoprofen.html)

my idea was to avoid doing a full round trip around the vascular system and just drop a small amount of aspirin so it would reach some organs but not the digestive system.

I "appreciate" the complexity of our systems, but do you suggest that even without physical proximity to your stomach aspirin can trigger cascades that can harm it ?

Considering its an acid.. I imagine it would hurt.
(comment deleted)
Everybody keeps mentioning Bayer. Have they had any innovation in the aspirin concept or is their marketing that effective?
Bayer was the company that originally developed aspirin, it was their trademark. At the time it was one of their two main products, the other being heroin.
what a coincidence, heroin a day reduced cancer risk 100%
They own the trademark "Aspirin" in many countries. In others that's a generic term.
I take a 325mg uncoated aspirin every morning on an empty stomach and have not seen any of those complications.

Totally agree that everyone should consult their doctor before beginning any daily medication whatsoever.

Yeah it seems some people can withstand it better than others

Id be hesitant to take anything over my 100mg

> An aspirin a day will also make your nose bleed after a few weeks

will? With 100% certainty? You are unnecessarily scaring people away from something that most assuredly does not cause bleeding in myself and many others.

Will, would, not really looking for an internet scaddadle, downvote me if wish

Daily aspirin use causes gastric distress ib many others, too.

My main point still stands, aspirin should taken with extreme care, and people reading stuff like this often think its a good idea to self medicate. Id rather they err(?) on the side of caution. Even though youre technically right. => "inappropriate use of aspirin MAY(would/could) lead to gastric bleeding"

If you are getting nose bleeds, you might benefit from getting more calcium in your diet. Upping my consumption of calcium put a stop to my nosebleeds.
I can see this being true. Also Xarelto and other drugs that can be used to prevent strokes are good for some things but the cons outweighs the pros for sure.
Or people who care enough to take an aspirin a day probably also take care of themselves better in other ways, which might be what keeps the cancer away?
What if they are hypochondriacs filled with anxiety and stress? -- feel like these people would definitely take an asprin a day out of fear.
Aspirin is metabolised to salicylic acid (SA) in the body. SA is a plant hormone found in many common food plants. I wonder if some of the health benefit of a plant-heavy diet can come from the SA. Maybe we are adapted to a certain level of SA intake, and eating aspirin helps us fulfill our SA "requirement" ... and then some, a baby Aspirin gives us 10-100x as much SA as a day's worth of plant-based food.
SA is also the active ingredient in wart removal balms, so there's that. Bio is SUPER complicated and really can't be reduced to first principals outside of breathe, drink, eat.
That's for directly topically burning the wart though. (Also for acne.) Ingested SA isn't going to burn off a warn before burning your while body from inside out.
Just an abstract. Limited or no peer review so be careful. Here's the text.

Background: Chemopreventive effect of aspirin on colorectal cancer (CRC) has been reported, but there are indications that effects of aspirin are not limited to the colon or rectum. The aim of this study is to evaluate the long-term use of low-dose aspirin at 80mg for other gastrointestinal (GI) cancers. Method: A territory-wide dataset which includes all patients admitted to public hospitals of Hong Kong were used to extract a cohort between 2000 and 2004 with long-term use of aspirin and matched against non-aspirin users in 1:2 ratio. Further matching on survival time with duration of aspirin prescribed for at least 6 months was conducted to avoid immortal bias. Patients' outcomes were documented for up to 14 years until 2013. Changes in cancer incidences on colon/rectum, liver, oesophagus, pancreas and stomach were the primary outcomes. Cancer related mortalities were the secondary outcomes. Odds ratio (OR) was used to measure the cancer incidence, and Sub-distribution Hazard Ratio (SHR) for competing risk mortality was fitted to adjust for other cause-ofdeath. Results: A total of 618,884 subjects were included; 206,295 aspirin users with average aspirin prescribed for 7.7 years were matched with 412,589 non-aspirin users. The mean ages of patients in aspirin and non-aspirin group were 67.5 years and 67.6 years respectively. The median dose of aspirin prescribed was 80mg, and inter-quartile range was from 80 mg to 100 mg. A total of 18,500 (2.99%) cases of CRC, 9,433 (1.52%) of hepatic cancer, 2,658 (0.43%) of oesophageal cancer, 2,796 (0.45%) of pancreatic cancer, and 5,877 (0.95%) of gastric cancer were observed. Long term used of low-dose aspirin showed significant reduction on cancer incidences for CRC (OR:0.76, 95% CI:0.73-0.78), hepatic cancer (OR:0.53, 95% CI:0.51-0.56), oesophageal cancer (OR:0.53, 95% CI:0.49-0.59), pancreatic cancer (OR:0.66, 95% CI:0.60-0.71), and gastric cancer (OR:0.62, 95% CI:0.58-0.65). Long term used of low-dose aspirin also showed significant reduction on mortality from GI cancers (Table 1). Conclusion: Long-term use of low-dose aspirin, at 80mg, significantly reduced both incidence and mortality from colorectal, hepatic, oesophageal, pancreatic and gastric cancers.

It’s not double blind. Aspirin takers might have other correlated behaviors which reduces cancer risks
In case you don't like pill popping, remember that many foods contain natural salicylates, including salicylic acid itself.

https://www.ncbi.nlm.nih.gov/pubmed/11493722

Great tidbit.

The advice always seems to come back to: "EAT YOUR DARK GREENS ALREADY!"

Spinach goes into my eggs every morning, and my poor girlfriend has suffered enough fresh salads with cucumber, broccoli and onion at my hands that she's come around to liking them — looking forward to them, and even requesting them. My god.

Eat your spinach!

Yes! And just remember, spinach is very healthy for you so long as your calcium/magnesium situation is balanced and you're drinking enough water and are moderate with caffeine/alcohol!

Spinach will help your urinary tract do what it's designed to do, but it needs your help!

I dunno, how can we be sure this isn't a long con by Big Arugula?
Correlation or causation?

Interestingly, the cancers that are most lifestyle related (liver, lung) are the ones seemingly most affected by taking aspirin.

Perhaps those taking aspirin are simply taking better care of themselves?

anything that reduces swelling and inflammation will probably reduce cancer risk, so its not surprising at all. although people seem to get upset by that fact.
There are meta-analyses of the RCTs for baby aspirin which also indicate reductions in all-cause mortality probably through its effect on cancer rates. I'd consider them much more important than this result which is ultimately just another correlational/observational result. Some of the studies I'm thinking of:

- Rothwell et al 2012 "Short-term effects of daily aspirin on cancer incidence, mortality, and non-vascular death: analysis of the time course of risks and benefits in 51 randomised controlled trials" http://www.istudymedicine.com/wp-content/uploads/aspirin.pdf

- "Effect of daily aspirin on long-term risk of death due to cancer: analysis of individual patient data from randomised trials" http://www.beppegrillo.it/immagini/Aspirin%20and%20death%20f...

- "Aspirin for prophylactic use in the primary prevention of cardiovascular disease and cancer: a systematic review and overview of reviews" https://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0083409/ , Sutcliffe et al 2013

- Pignone et al 2013, "Effect of including cancer mortality on the cost-effectiveness of aspirin for primary prevention in men" https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3797356/

- "Estimates of benefits and harms of prophylactic use of aspirin in the general population", Cuzick et al 2014 http://annonc.oxfordjournals.org/content/26/1/47.full

- Cuzick et al 2015, [Estimates of benefits and harms of prophylactic use of aspirin in the general population" https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4269341/)

I really look forward to big (hopefully open data) and health services to merge more. This could be one of the great wealths of information for the 21st century to progress health and treatment.

If the governments put half as much effort into spying on our heath decisions and putting that data out there I'm guessing it would save more lives than current efforts!

> [blah blah blah], study suggests

Nobody outside medical research should pay the slightest attention to to anything a study suggests, especially not if they're ignoring what many studies give strong evidence for.

Nothing to see here.

I'm possibly misreading you here... But:

You do know that it's not literally a study walking up to some journalist, speaking the words "I suggest some Aspirin!", right?

...because you seem to put some rather misplaced importance on the exact phrase used to introduce the study.

Yes, I'm aware that studies do not converse with people.

When someone says a study "suggests" something, I understand them to mean that it gives very tentative evidence. Such evidence is frequently contradicted by other studies: see https://www.sciencealert.com/images/art-apr-15/Medical_studi..., which another commenter has linked.

If one study suggests that eggplants may prevent heart disease, you can pretty much bet that another will suggest it causes it.

That's why I'm saying to ignore this. We would all do well to eat better and exercise more, suggestions that are well-supported by many studies. If we're not doing that, we're certainly wasting our time on uncertainties like this.

From what I can see, there's no control-group, so it's showing correlation, and not causation.

I read that people who floss daily live longer too. It's not because they floss, but the ones who floss are more likely to have healthier lifestyles in general. This study seems to fit into the same bracket.

(comment deleted)
Aspirin always makes my stomach hurt terribly. Even low dose aspirin makes me feel like I have an ulcer. I wish I could take it...
I hear you... I'm in the same boat. I've tried it many times, but my stomach wasn't happy about it.
I take it and wish i didnt need to. Life's full of ironies.
https://en.wikipedia.org/wiki/Essential_fatty_acid_interacti... . Some recommended keywords that are not mentioned in the article: inflammation, essential fatty acids (EFA), and the Arachidonic Acid Cascade.

A feature that significantly distinguishes modern diets, especially after the advent of "vegetable" oils and grain-fed meat, is the ratio of omega-6 to omega-3 (the two types of EFA).

Aspirin works by irreversibly inactivating the cyclooxigenase enzyme, which is involved in the Arachidonic Acid Cascade. https://en.wikipedia.org/wiki/Mechanism_of_action_of_aspirin

Edit: Added last parragraph.

EVERYONE BUYI ASPIRIN NAO
Here are two more studies suggesting that aspirin reduces cancer [1] [2]. The second is from 2014 but is particularly compelling because it assessed whether the drop in cancer was worth the increased risk of stomache bleeding.

The head of that study said that taking aspirin "looks to be the most important thing we can do to reduce cancer after stopping smoking and reducing obesity, and will probably be much easier to implement"

[1] https://www.scientificamerican.com/article/aspirin-may-preve...

[2] http://www.theguardian.com/science/2014/aug/06/aspirin-could...

Unless you have strong preferences on the diseases you end up getting, isn't the important thing aspirin's effect on total all-causes morbidity/mortality?
>If taking aspirin were without side-effects and completely risk free, it might make sense for everyone with heart disease, or just worried about it, to take it. But aspirin does have risks. Reducing blood's clotting potential can lead to hemorrhagic stroke (bleeding inside the brain). In the stomach, aspirin can cause everything from a feeling of mild heartburn to bleeding ulcers. Severe gastrointestinal bleeding can be deadly.

https://www.health.harvard.edu/healthbeat/should-everyone-ta...

It's ... complicated:

"for every 1000 patients treated for a 5-year period, aspirin therapy would be expected to result in 1 excess hemorrhagic stroke compared with a benefit of ≈14 myocardial infarctions prevented in patients at moderate risk for CHD (5% to 10% 5-year risk)"

http://stroke.ahajournals.org/content/36/8/1801

"Aspirin has been found to be a safe in patients harboring cerebral aneurysms and clinical studies provide evidence that it may decrease the overall rate of rupture."

https://www.ncbi.nlm.nih.gov/pubmed/25967073

"There was an approximately 40% increased risk of all gastrointestinal bleeding with low-dose aspirin in the observational studies reviewed here, a finding very similar to that reported in randomized trials"

"The overall risk of intracranial hemorrhage was also increased by approximately 40% with long-term low-dose aspirin, which is also similar to the estimates from randomized trials, although an increase in risk was not consistently reported in all studies."

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4973997/

"Aspirin reduced the 6 week risk of recurrent ischaemic stroke by about 60% and disabling or fatal ischaemic stroke by about 70%"

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5321490/

"aspirin significantly reduced the risk of myocardial infarction among men by 43%"

"significantly increased risk of major extracranial bleeding with aspirin [RR 1.54]. The excess risk of bleeds was mostly non-fatal. Perhaps by chance, fatal gastrointestinal (GI) or other fatal extracranial bleeds were lower in the aspirin group versus control [RR 0.48]"

"In a meta-analysis of eight trials including 25,570 patients, aspirin use significantly reduced the overall incidence of cancer-related death by 21%"

"In the meta-analysis of six trials, an increased risk of extracranial bleeding was observed with low-dose aspirin; however, the analysis of extracranial bleeding stratified by period of follow-up revealed that the risk of extracranial bleeding decreases over time, becoming comparable to that of placebo or no aspirin from 3 years onwards: <3 years"

"In this same analysis, fewer cases of fatal bleeding were associated with aspirin use, compared with controls [OR 0.32]"

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4383813/

Even with the side effects and risks it might make sense for almost everyone who is aged 60 to take aspirin every day.

There is now good evidence [1] that if 10,000 people aged 60 took aspirin for 20 years there would be:

174 fewer deaths from cancer and heart attacks

24 more deaths from strokes, ulcers and gastric bleeds

So it seems that the benefits far outweigh the costs.

[1] http://scienceblog.cancerresearchuk.org/2014/08/06/aspirin-a...

I ate an entire box of baby aspirin when I was a kid. Seriously. I clearly remember hiding under the bed while crunching away. Nothing happened.

Come to think of it, I got the flu twice in 30 years.

Study suggests that consuming an entire box of baby aspirin causes reoccurring flu.
Beware also that Aspirin allergy is a thing and often accompanies a general allergy to NSAIDs such as Ibuprofen. In my own case the allergy results in a moving facial swelling (angioedema) which my family dubbed 'Quasimodo Face' before we realised the cause. This effect lasted a day. I had it a few times before I worked it out. The allergy came on after a period of work stress and minor illness where I was taking Ibuprofen to get through the day.
Cancer Research UK has great articles on taking aspirin both to prevent cancer [1], and to prevent the spread and recurrence of cancer [2]

Their tweets [3] today on the topic lay out the current situation pretty clearly

Quoting their tweets and blog post:

"Aspirin can help protect against bowel cancer, and possibly stomach, oesophageal and other cancer too"

"Aspirin also increases the risk of strokes and stomach bleeding"

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

[1] http://scienceblog.cancerresearchuk.org/2014/08/06/aspirin-a...

[2] http://about-cancer.cancerresearchuk.org/about-cancer/cancer...

[3] https://twitter.com/CR_UK/status/925323615360487425

I find the advice given by Cancer Research UK in your first link quite strange.

They seem to accept that if 1000 people aged 60 took aspirin for 20 years there would be:

17.4 fewer deaths from cancer and heart attacks

2.4 more deaths from strokes, ulcers and gastric bleeds

That's a net reduction of 15 deaths per 1000 people. Yet before they recommend that everyone aged 60 take aspirin, they want to know:

a) What age should people start, and stop, taking aspirin?

b) What dose should they take?

c) What are the factors that should rule someone out from taking aspirin, and how should we test for them?

Here are my answers to Cancer Research UK:

a) People whose age would put them within the study cohort. From my reading this is at least people aged 60 for 20 years

b) They should take the dose that was looked at in the study

c) We don't know what factors should rule someone out, but until we do know we should recommend aspirin to everyone who would have been within the cohort study.

There are probably around 10 million people aged 55-65 in the UK. 15 extra deaths per 1000 people means an extra 150,000 deaths over 20 years.

So the cost of waiting for more studies is about 7 extra deaths per day in the UK alone. Cancer Research UK is being too hesitant in its recommendations.