> but makes no such effort for studies on plant-based foods
. . . specifically whole plant-based foods. He describes the health problems of hydrogenated oils, sugar, and products made from them.
Is there a whole plant based food industry funding studies on broccoli and collard greens? If not, is he biased or simply stating what his research implies?
Yes there is. Almost every major class of produce has an industry association (or several) which promote the interests of their industry, including funding research. In fact, a family member of mind sits on the board of two such associations in California, one for peach growers and one for tomato growers, both of which have funded tons of research out of UC Davis.
That isn't to say that the research is flawed, but somehow Greger only sees this funding mechanism to be fundamentally bad when they contradict his predetermined conclusion...he conveniently doesn't see any reason to question a study on kale funded by the kale industry.
And yes, Greger is biased. His opinions start with the premise that vegan==good and anything else is bad, and he works backward from there to shape a view of research that bolsters that premise. It's no different than Mormon scientists attempting to prove that coffee is bad for you, or Muslim scientists that attempt to prove that pork is bad for you. The idea that humans shouldn't eat animals or animal products has a valid philosophical foundation, and while a vegan diet is likely far more healthy than the average diet, editorializing the science to attempt to prove nutritional superiority of that philosophy is irresponsible pseudoscience.
> It's no different than Mormon scientists attempting to prove that coffee is bad for you, or Muslim scientists that attempt to prove that pork is bad for you.
Assuming the proper procedures are observed I don't think I see something wrong in principle with these examples. Certainly if they're massaging the data we're talking about something different.
There is certainly no problem doing a study and having a hypothesis that X is bad. There is a huge problem with going through the literature and selecting studies that agree with your point. Part of the problem lies in the fact that X is usually not completely good nor completely bad.
For example, let's say that 10% of all studies are poorly executed. If there are 100 studies that conclude that X is good, I can find 10 of them that are poorly executed. Let's say there are 20 studies that conclude that X is bad. If 10% of them are poorly executed, then I can find 18 which are well executed. In reality there are 90 good studies concluding that X is good and 18 good studies concluding that X is bad. However, I can show the 10 poor studies showing something is good and the 18 well done studies showing it is bad, leading you to conclude that there is some kind of conspiracy, even though most of the evidence concludes that X is good.
Meta studies are particularly prone to selection bias in this way.
If they're principled about the science and the procedure, sure. The problem with deeply held philosophical or religious beliefs in science is when they start with the conclusion and then contort the process to arrive at that conclusion.
>Assuming the proper procedures are observed I don't think I see something wrong in principle with these examples. Certainly if they're massaging the data we're talking about something different.
Already "trying to probe X" is a bias. And if you have a religious or monetary interest on top, you shouldn't be doing such research in the first place.
Even if you intend to follow all correct procedures, your prior beliefs might still affect your results subconsciously.
Everybody has some kind of bias. Should a scientist be barred from studying greenhouse gas emissions if he is a known advocate of curtailment of fossil fuels? If not, why is that different?
>Should a scientist be barred from studying greenhouse gas emissions if he is a known advocate of curtailment of fossil fuels?
Probably.
>If not, why is that different?
It's not.
(Now, sure, they could do it. In fact, they do do it. It's not like my opinion is law. That said, historically, researchers with some personal bias had all kinds of problems related to that in their research -- many examples).
Clearly we're seeing some real-world issues with the actual practice of science, but the concept is that if researchers are carrying it out properly it doesn't matter what their personal beliefs are. You start out with a hypothesis, design an experiment, and it either proves you right or wrong. I don't think it's necessary or even desirable to start interrogating beliefs and only selecting scientists we somehow judge completely unbiased; if we followed that to extremes we'd end up with a case where the same scientist could not even continue studying the same subject.
>but the concept is that if researchers are carrying it out properly it doesn't matter what their personal beliefs are. You start out with a hypothesis, design an experiment, and it either proves you right or wrong.
Yeah, but note how this presupposes that its equally easy to "carry it out properly" in either case.
Whereas what I say is that
(a) it's less likely for biased researchers to carry their research out properly (I say less likely, not impossible).
(b) so for that, we should try to have less research from biased researchers
(That's because I don't think that "(c) biased researchers should try more to handle their research properly" is an option -- because of how bias works, biased researchers will always be more prone to not handling their research properly).
. . . specifically whole plant-based foods. He describes the health problems of hydrogenated oils, sugar, and products made from them.
Is there a whole plant based food industry funding studies on broccoli and collard greens? If not, is he biased or simply stating what his research implies?