i get this all the time: hey, i saw your video but then i saw this other video and it said the exact
opposite, so who do I trust? easy. you don't. science isn't based on trust, it's based on confirmation. or
as we say in nerd speak, reproducibility. of course, this is completely understandable, we don't have
the time to go read 100 studies every time we got to make a decision, so we look for somebody who's
going to give us the answers, somebody we can trust. problem is, if i don't know much about a topic, then
i don't know enough to know who's right and who's wrong. if i know enough to fact check the experts,
i don't need an expert, but if i need an expert because i don't know enough, then i don't know
enough to know who's an expert. so we all do the same thing, we use shortcuts, like the vibe we get
from the person, or professional titles, or how popular they seem. but we greatly overestimate
how good our judgment really is. research has shown our brain makes snap judgments that subconsciously
guide our decisions. would you trust this man? how about this one? or this one? these faces might look
similar, but psychologists found subjects responded differently, implicitly trusting the picture on
the right the most. this effect was so strong that even after telling the volunteers about a
history of untrustworthiness for that individual, facial features still influenced how much they
trusted him. we also tend to trust people who just look like others who were reliable in the past,
and vice versa, we tend to mistrust people who look like others who screwed us over. psychologists have
shown we even trust people more if they look like us. maybe this was advantageous to our
ancestors, people who look like me are more likely to be my relatives, so if my entire world is a
tribe of 100 people, this might help a bit, but nowadays interacting with thousands of people on
the internet, this is a disaster waiting to happen. credentials and degrees, those are really tricky
too, just spend five minutes on the internet, you'll find a bunch of MDs saying the exact opposite on a
factual claim, so somebody's got to be wrong, which means the title is no guarantee of anything. and
needless to say, going by personality, likability, charm, who seems honest, who says it like it is,
massive pitfalls. somebody can be 100% sincere and 100% wrong. basically, the trick is to focus less
on the individuals and more on the concepts or the ideas. less on the who, more on the what. this
is very unnatural to us because our brains want to do the exact opposite. so we're going to give
you a framework. we're going to look at three major red flags, the three As to avoid. and
after that, we're going to look at three tips that actually do work to distinguish reliable sources
the three Ps. P for positive. and yes, these rules apply to me as well, of course, and you should hold
me and everybody else to the same criteria. okay, so here are the red flags, the three As. first A is an
over-reliance on anecdotes. we're wired to connect with anecdotes, they just resonate with us. bar
graphs and p values, not so much. but anecdotes are notoriously unreliable, they involve many variables,
there's placebo effect, there's the lack of a control group, you name it, it's a mess. so you want
to be careful with arguments that rely heavily on anecdotes. and nobody's immune to it, we actually
released a video on salt recently and i talked about a salt substitute and i showed some studies
showing effectiveness, and then i mentioned that i got the same salt substitute and my blood
pressure went down and some family members, and an attentive viewer wrote in and he said, that was an
anecdote in the middle of that video, and i thought about it, i looked at it, and you know what,
he's right, so we went back, we deleted that, we deleted that segment where i made that statement
so if you go watch the version of the video that's live, that sentence is now gone. not that it's the
end of the world to mention an anecdote, as long as we're not basing a scientific argument on it
and especially if we mention the limitations, right? but i thought the viewer made a valid point
and i thought the video was probably stronger without that remark
and also, if we're criticizing and trying to set the bar high, we got to be ready to take some
criticism as well and walk the walk. so that got cut. i just realized that whole story was
basically an anecdote. so i ragged on anecdotes by using an anecdote. yep, we're doomed. okay,
the second A stands for antagonism. we've all seen different online communities, or people sometimes
whose entire world view is "us versus them". our diet, diet A, is perfect, and those guys over there, diet B,
are all a bunch of morons. and the third A stands for anger. we want to avoid coming at this from a
place of frustration, crystallized in this very common idea of "they lied to us". "they" being
sometimes the government, sometimes scientific establishment, sometimes the status quo, etc. so
this, the antagonism, fighting everybody who has a different opinion, and the anger, this is not
a good head space to look at things objectively and just try to figure stuff out, it more likely
warps our perspective and blinds us. now, we all make mistakes, nobody's perfect, we all have our
moments of weakness, so the idea here is not to point fingers, but you're looking for a pattern,
right? a pattern of calm and objectivity and curiosity or a pattern of antagonism and anger
and frustration at another group or groups. and on that note, let's keep it positive and
look at the three Ps. and i should mention i came up with this jointly with Simon Hill
from The Proof podcast and we actually broke this down in more detail in a recent episode that i was
on with him and i'll link that below but this is the gist, right, this is the one or two minute
summary. just the juice. first P stands for proof. the burden of proof lies with the person
making the claims. now, this seems obvious it's almost like a duh, right? but you'd be surprised
i get messages all the time from people who say "i'm really confused by this blog or this podcast"
and it turns out it's just a bunch of claims with zero evidence. you don't need to be confused
by just claims, there's something called hitchen´s razor, named after the writer christopher hitchens
"that which can be asserted without evidence can be dismissed without evidence". so if it's
unaccompanied by evidence, yeah you can just move on. this rules out 90% of internet confusion. i saw
this really interesting comment the other day by one of the viewers, one of you guys, he said "hey,
really interesting videos, really thought-provoking, but i'm not sure, because you guys keep saying
stuff that doesn't really match what the other youtubers are saying...". yeah, that's the whole reason
we make these videos, the whole reason i started making these three or four years ago, whatever
it was, was that you look systematically at the scientific evidence and you see one thing
and then you look at the internet and you see wild claims, sometimes it's the exact
opposite. so point is, worry less about what people say and worry more about the evidence they
show. yes, including me. okay, second P stands for preponderance. strong scientific arguments are
based on a body of evidence, as opposed to isolated studies. we've all heard this type of argument:
"there's a study for every idea out there, they have theirs over there and i have my own studies that
support my view". this is social media bickering, right? tussling. but a serious scientific approach
looks at all available evidence and it strives for a model that reconciles everything. so if i want to
figure things out, i look at the full picture, but if i just want to prove my point, that the picture
is red, then i just focus on the corner I like. and finally, the third P stands for pyramid. pyramid refers
to the hierarchy of evidence. all evidence is not created equal. so you want to watch out for claims
based on mouse data, or a tribe somewhere in the amazon, what's called ecological data. these are the
weakest forms of evidence, the lowest rungs of the pyramid. the mouse data is pretty self-explanatory,
it doesn't tell us what happens in humans. what about looking at a specific population?
that's humans, why is that weak data? let me give you an example. people ask me this all the time,
hey, in japan they eat this food a lot and they're pretty healthy over there, doesn't that prove that
that food is good? or bad, in some other examples. france has a very high rate of smoking, over a
third of french people smoke, and yet it has one of the highest life expectancies in the world
when we look at a country on the opposite end of the spectrum, in nigeria less than five percent
of people smoke and yet it has one of the worst life expectancies in the world. when we put it
like that, every single one of you can immediately see through that argument, right? it doesn't mean
that smoking makes you live longer, it means that these cross-country comparisons involve
thousands of moving pieces, of confounders, right? from genetic differences to culture, to quality
of healthcare, to overall quality of life in that country. this is why you want to focus on
the upper rungs of the pyramid. evidence in humans, well-designed, reasonably matched groups, and where
you make an effort to isolate a variable, either by randomizing the participants or by adjusting for
the differences. that means well-designed cohort studies, randomized clinical trials and finally,
meta-analyses. meta-analyses also help you get at preponderance, the second P, because they give you a
snapshot of the big picture. so this information gives you a simple and an actionable framework.
if you hear somebody making claims and there's no evidence, you spot it. if the evidence is in
mice or rats and the claim is for humans, you spot it. if the evidence is in a tribe somewhere
in an island, boom, you spot it. right? and you're always looking for evidence higher up that pyramid
alright, i hope that helps, and as always, let me know your thoughts below, and we got a lot of
exciting videos coming out, from gut health to questions about protein to effects of
food on mental health, all kinds of fascinating stuff, so stay tuned, take care, see you next time, bye