= 27d567bc2d48d9f40e9ccc20ea370b15)
CasioTheSane comments on Daily Low-Dose Aspirin, Round 2 - Less Wrong
You are viewing a comment permalink. View the original post to see all comments and the full post content.
= 783df68a0f980790206b9ea87794c5b6)
Loading…= b715d02e85f7b3b4ae65ca3d3e450868)
Subscribe to RSS Feed
Powered by Reddit
= f037147d6e6c911a85753b9abdedda8d)
You are viewing a comment permalink. View the original post to see all comments and the full post content.
Comments (20)
It appears that the evolutionarily unprecedented high omega-6 and low omega-3 intake in the modern western diet causes excessive series-2 prostaglandin and thromboxane (TXA2) formation, and resulting inflammation and cardiovascular effects- and low dose aspirin is an attempt to combat this. Why not fix the problem at it's source?
Reducing omega-6 oils in your diet and increasing omega-3 should have a similar effect, but with more proven safety and effectiveness: nearly all humans did this until industrial seed oils became popular in the last few decades (see this video series from biochemist Dr. Bill Lands for more details http://youtu.be/dgU3cNppzO0 ).
Aspirin works primarily by suppressing production of thromboxane and inflammatory series-2 prostaglandins from omega-6 fats, by inactivating the cyclooxygenase enzymes (COX-1, and COX-2). Omega-3 fats also competitively inhibit this same enzyme, by competing with omega-6 fats to be metabolized into less inflammatory series-1 and series-3 prostaglandins.
There are other important benefits of fixing the omega 3/6 ratio in your diet as well- their ratio is reflected in tissue lipid membranes, and likely influences the proper function of these membranes. Continuing on a high omega-6 diet and trying to counter-act this with aspirin seems less than ideal.
It would be interesting to see some data showing the effectiveness of low dose aspirin in countries that already have a healthy omega 3/6 ratio (such as Greenland or Japan). I would be very surprised if it still has the same benefit in such a group.
As a person who has a nearly 1/1 omega-6 to long chain omega-3 ratio in my diet (I regularly eat fatty cold water fish and avoid seed oils), I wouldn't consider low dose aspirin to be a prudent risk adverse decision unless I saw data showing it's benefits reproduced in others with a similar intake ratio.
I retracted this, because I have learned a lot more about this issue in the last year. I am still undecided on aspirin, however I no longer think that the mechanisms mentioned above are the only important roles aspirin plays. I am also no longer convinced that omega-3 offers a health benefit, and that omega-6 restriction alone may be superior to replacing omega-6 with omega-3.
If you look at the Rothwell paper linked above by gwern, there's one Japanese study there - JPAD (Ogawa H, Nakayama M, Morimoto T, et al. Japanese Primary Prevention of Atherosclerosis With Aspirin for Diabetes (JPAD) Trial Investigators. Low-dose aspirin for primary prevention of atherosclerotic events in patients with type 2 diabetes: a randomized controlled trial. JAMA 2008; 300: 2134–41).
Looking at the graphs, JPAD effectively showed zero effect of aspirin. I think this supports your thesis.
But from JPAD, the specific effects that are supposed to show aspirin benefits weren't what this study measured! They were looking at:
This doesn't include anything related to cancer. And to the extent that the study did look at all-cause mortality, it showed exactly what you would expect from a relatively small (n=2539) and short ("median follow-up of 4.37 years") trial where aspirin was yielding benefits: a large but non-statistically-significant effect
I haven't looked at the JPAD paper yet, but that Cochrane study plots JPAD results for cancer endpoints as well as major vascular and extracranial bleeds. In the same graphs I don't see large effects.
It's worth pointing out the general low cancer rates (in the controls as well) in the JPAD study.