About that John Hawks's evolutionary argument - "if humans with smaller brains could manage, lesser energy requirements would select for this":
I wonder if maybe having larger brains didn't bring extra survival advantages thanks to having available "spare capacity".
From modern day sports we know how bad head injuries can be (boxing, American football, soccer). If in our evolutionary history a chance of brain damage was common, larger brains could be difference between "brain damaged but still functional" and "brain damaged and dead".
Interesting side-effect could then also be availability of this extra capacity for other functionality in individuals which managed to escape brain damage.
When taking baby Aspirin and having anticipated bleeding (e.g. planned surgery or dental work), hematologist's advice was to start preparing about two weeks in advance: take pill every other day for about a week, then stop for another week.
This paper tells The American College of Chest Physicians' recommendation is stopping 7-10 days in advance, in the clinical study they measured 96 hours (4 days) for "normalizetion of platelet reactivity":
Science is amazing. Don't forget to make it relatable by doing work like this! People love to see great images, so you gotta curate them and highlight the stunning stuff like this!
Credit should go to landru79, he keeps finding interesting things in Rosetta's raw data. I basically just tried to correct for Twitter's terrible video handling by re-tracing his steps :)
Go check landru79's Twitter feed, there are many more interesting comet images and videos (e.g. he combines multiple frames into color images):
"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)"
"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."
"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."
"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]"
Amounts of vitamins per supplement seem to vary wildly.
Just from checking supplements I have at home:
Supplement #1 (all B vitamins):
- B6: 4.2mg
- B9: 600ug
- B12: 7.5ug
Supplement #2 (just B6 + B9 + B12):
- B6: 75mg
- B9: 800ug
- B12: 150ug
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Recommended daily doses are:
- B6: 1.7 mg/day (men)
- B9: 400 ug/day in US, 330 ug/day in EU (men + non-pregnant-non-lactating women)
- B12: 2.4 μg/day in US, 4.0 μg/day in EU (men + non-pregnant-non-lactating women)
Tolerable upper intake levels are:
- B6: 100 mg/day in US, 25 mg/day in EU
- B9: 1000 ug/day
- B12: no sufficient evidence for setting upper level
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From the study:
Beneficial effects (for men):
- B6: 1.41 - 3mg/day, multivitamins
- B9: 200 - 400 mg/day
- B12: 0.1 - 55 ug/day
Harmful effects (for men):
- B6: > 20mg/day
- B9: 400 - 600 mg/day
- B12: > 55ug/day
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Also something to keep in mind: apparently the majority of people in this study who got lung cancer were heavy smokers for many years, even if they stopped smoking.
Hard to tell much about B vitamin supplement effects on non-smokers from this study.
Researchers themselves excluded never-smokers from more detailed stratified analysis because of their small number.
There were only 60 cases of lung cancer in never-smoker category (out of 36,381 people => 0.16%).
In comparison there were 748 cases of lung cancer in smoker categories (former + recent + current) (out of 40,737 people => 1.84%).
So there is 11.5x higher risk of lung cancer simply by smoking (including people who stopped smoking).
For comparison the highest hazard ratio from this study was 3.71x for a category of current smoker taking >55ug/d B12 vs current smoker who is non-user of B12.
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Also curiously, the worse risks seem to be associated with people who stopped taking vitamins than people who currently use vitamins (B6: 1.97x vs 1.38x, B9: 1.65x vs 1.05x, B12: 2.58x vs 1.19x - individual supplement use status former vs current).
Plus smaller doses of B6/B9/B12 shown in this study to pretty much universally lower lung cancer risk by a bit (hazard ratios of 0.8-0.9x ranges; one noticeable outlier >600ug/d B9 in recent smokers halving risk of cancer).
Some people hate statistics for a reason, and this is the exact reason. It is outrageous how the author conveniently manipulated the data to support the claim in their paper.
For those of you who want to do your own analysis, assuming their data are authentic, take a look at their Table I:
- past smoker (stopped > 10 years ago): 8.9x higher risk
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Take home message: stop smoking!
Precautionary principle: if you take B vitamin supplements, you can continue (for slight decrease of cancer risk), just make sure you aren't taking mega-doses (especially if you still smoke), but really - stop smoking - the sooner you do less cumulative harm you get.
I wonder if maybe having larger brains didn't bring extra survival advantages thanks to having available "spare capacity".
From modern day sports we know how bad head injuries can be (boxing, American football, soccer). If in our evolutionary history a chance of brain damage was common, larger brains could be difference between "brain damaged but still functional" and "brain damaged and dead".
Interesting side-effect could then also be availability of this extra capacity for other functionality in individuals which managed to escape brain damage.