As you point out so well, diet studies, especially those relying upon self-reporting, are fraught with errors. Meta-analyses suggesting trends, rather than single studies giving percentages, are far more persuasive, but don't seem to inspire as many headlines.
It's hard to get people interested in study methods. We're busy; we just want to know the takeaway.
I wish high school curricular standards made more room for supporting data literacy, because even kids at that age can appreciate the difference between one crappy observational study vs. a well-done meta-analysis (even if the stats are beyond what's covered in AP Statistics).
Countries such as Finland begin teaching critical thinking skills in elementary school. Just another area where the U.S. lags behind other developed nations.
Nice work and agree with your assessment of what seems to be an arbitrary and capricious criteria for the processed groups with rather low bars. You mentioned the "Informational siloing also seems to be occurring." This reminded me of the new proposed dietary guidelines that emphasise plant based over meat I shared earlier this month. Seeing the same thing, of course, thin s might have changed since then. Guess there is a global plot to take away your burger. Anxieties at the Petri Dish - by KB's FROM THE PETRI DISH
Next posting is going to look at a few things on diets, the gut biome and brain/ling/heart axis. Suspect there is an underlining commonality to this and other medical conditions.
It's sad to see that issues like diet-health relationships are so deeply politicized. I understand that people are going to follow party lines when debating trade-offs between the economic benefits and the environmental damage created by the cattle industry, for instance, but it's a shame we can't just set politics aside when looking at the impact of beef consumption on health and let the data lead wherever it may.
Dementia or Alzheimers is an interesting endpoint, too, because cured meats like hot dogs and salami and pepperoni are fairly significant hazards for various cancers (1.1 - 1.4 HR), and of course red meat is also a significant CVD hazard (1.1 - 1.3 HR depending on unprocessed vs processed and consumption), likely due to saturated fat (and nitrites and nitrates in the processed / cured ones).
There's not necessarily any direct relations between those endpoints and dementia, but it definitely feels like there's probably additional dementia risk if you have CVD or higher cholesterol (and correspondingly higher inflammation), or if your body is under additional immunological and inflammatory load from the increased cell turnover driven by cured meats.
And their dosing is terrible as you point out, as a lot of the dose-response for the other endpoints are usually driven by each incremental 50 grams of consumption. Did they even calculate a dose response at all?
Good point. Definitely see studies linking CVD etc. to dementia.
I was startled not to find dose-response analyses in this one. They do have the data. This feels a bit like a researcher degrees of freedom problem, in the sense of their having chosen the analytic approach that yields the most favorable results.
Part of the reason I say that is the authors were noticeably vague about explaining the cut-offs for low, medium, and high intake. Their only justification is a reference to published standards "while also considering the distribution of intake among study participants." Ok, but what does that "also" mean? This fails one of those standards for scientific writing we teach undergrads, where you're supposed to describe your methods so clearly that someone else could replicate your work. Here too, I'm concerned that intake was simply trichotomized in a way that produced the strongest outcomes.
As you point out so well, diet studies, especially those relying upon self-reporting, are fraught with errors. Meta-analyses suggesting trends, rather than single studies giving percentages, are far more persuasive, but don't seem to inspire as many headlines.
It's hard to get people interested in study methods. We're busy; we just want to know the takeaway.
I wish high school curricular standards made more room for supporting data literacy, because even kids at that age can appreciate the difference between one crappy observational study vs. a well-done meta-analysis (even if the stats are beyond what's covered in AP Statistics).
Countries such as Finland begin teaching critical thinking skills in elementary school. Just another area where the U.S. lags behind other developed nations.
Nice work and agree with your assessment of what seems to be an arbitrary and capricious criteria for the processed groups with rather low bars. You mentioned the "Informational siloing also seems to be occurring." This reminded me of the new proposed dietary guidelines that emphasise plant based over meat I shared earlier this month. Seeing the same thing, of course, thin s might have changed since then. Guess there is a global plot to take away your burger. Anxieties at the Petri Dish - by KB's FROM THE PETRI DISH
Next posting is going to look at a few things on diets, the gut biome and brain/ling/heart axis. Suspect there is an underlining commonality to this and other medical conditions.
Interesting plan for your next posting.
It's sad to see that issues like diet-health relationships are so deeply politicized. I understand that people are going to follow party lines when debating trade-offs between the economic benefits and the environmental damage created by the cattle industry, for instance, but it's a shame we can't just set politics aside when looking at the impact of beef consumption on health and let the data lead wherever it may.
Dementia or Alzheimers is an interesting endpoint, too, because cured meats like hot dogs and salami and pepperoni are fairly significant hazards for various cancers (1.1 - 1.4 HR), and of course red meat is also a significant CVD hazard (1.1 - 1.3 HR depending on unprocessed vs processed and consumption), likely due to saturated fat (and nitrites and nitrates in the processed / cured ones).
There's not necessarily any direct relations between those endpoints and dementia, but it definitely feels like there's probably additional dementia risk if you have CVD or higher cholesterol (and correspondingly higher inflammation), or if your body is under additional immunological and inflammatory load from the increased cell turnover driven by cured meats.
And their dosing is terrible as you point out, as a lot of the dose-response for the other endpoints are usually driven by each incremental 50 grams of consumption. Did they even calculate a dose response at all?
Good point. Definitely see studies linking CVD etc. to dementia.
I was startled not to find dose-response analyses in this one. They do have the data. This feels a bit like a researcher degrees of freedom problem, in the sense of their having chosen the analytic approach that yields the most favorable results.
Part of the reason I say that is the authors were noticeably vague about explaining the cut-offs for low, medium, and high intake. Their only justification is a reference to published standards "while also considering the distribution of intake among study participants." Ok, but what does that "also" mean? This fails one of those standards for scientific writing we teach undergrads, where you're supposed to describe your methods so clearly that someone else could replicate your work. Here too, I'm concerned that intake was simply trichotomized in a way that produced the strongest outcomes.
I was eating a cheeseburger whilst reading this. I'm reconsidering.
You'll be fine. Can't say the same for the cow. :)