[@PeterAttiaMD] Cooking with Lard vs Seed Oils | Layne Norton, Ph.D.

Link: https://youtu.be/7_cbaDXAWYM

Duration: 12 min

Short Summary

This episode examines the science behind seed oils, oxidation during frying, and the debate over saturated fats versus unsaturated oils for cardiovascular health. Host Lane and guest Peter discuss that no direct human RCT compares frying with lard versus seed oils, while presenting converging evidence that apoB-containing lipoproteins are atherogenic based on Mendelian randomization studies and statin trials. Practical takeaways include limiting saturated fat, eating enough fiber, and prioritizing larger health factors over seed oil concerns.

Key Quotes

1. "My PhD adviser used to say, "If I wanted to design a study to show no effect or the study to show an effect, easiest thing in the world."" (00:12:31)
2. "people think food companies care about which foods you buy. They just want you to buy." (00:07:15)
3. "you can never prove anything, right? Like we can only disprove things, but we can have relative degrees of confidence in various data, right?" (00:13:52)
4. "It's like we're we're stepping over $100 bills picking up pennies, you know?" (00:19:02)
5. "the average calorie consumption in the United States is 3,500 calories per day, and the average physical activity is less than 20 minutes per day." (00:18:46)

Detailed Summary

Seed Oil Processing and Oxidation Science

The episode discusses seed oil processing, explaining that it occurs under vacuum with virtually no oxygen, resulting in minimal oxidation even when heated, unlike restaurant frying conditions. Research presented shows that oil thickness significantly impacts oxidation rates—moving from 1 cm to 5 cm depth creates a huge difference, with thin-layer frying producing negative products within 20-30 minutes. Continuous heating of oil in restaurant frying vats leads to significant oxidized trans fats accumulation over time. Saturated fats are noted as less prone to oxidation when heated compared to polyunsaturated fats.

The Seed Oil vs. Saturated Fat Debate

The speakers examine the controversy around seed oils versus saturated fats like lard and tallow. Lane points out that food companies market whatever sells, and switching to tallow/lard can be misinterpreted by consumers as healthier, potentially increasing consumption. Peter raises the question of whether, if LDL can be controlled pharmacologically with statins, the focus should shift to other potential harms like oxidation products from frying oils. A key admission is that no human RCT exists comparing health outcomes of frying with lard versus seed oils, as competing mechanisms make it difficult to determine which is worse.

apoB and Cardiovascular Health Evidence

Lane expresses high confidence that apoB-containing lipoproteins are atherogenic based on converging evidence, especially Mendelian randomization studies and statin trials, though would require substantial data over time to change this view. The discussion addresses whether aldehydes and oxidation products from frying oils become more important health concerns after addressing LDL with statins. Both speakers emphasize that there are elements of truth to criticisms of seed oils, but the balance across hard outcomes must be considered.

Scientific Rigor and Study Interpretation

The episode emphasizes relying on converging lines of evidence and the most high-quality, rigorously controlled studies. Lane notes that 99 out of 100 times reading the actual scientific study explains seemingly weird outcomes, often due to control group design or group level differences. A PhD adviser is quoted stating that designing a study to show no effect or a specific effect is "the easiest thing in the world." The scientific principle is highlighted: you can never prove anything in science, only disprove things; we can only have relative degrees of confidence in data. Every study has limitations, but pointing out limitations doesn't mean a study is bad—interpretation should be careful about how broadly results apply.

Practical Recommendations and Summary

For those avoiding seed oils, the recommendation is to displace saturated fat with leaner protein sources and lower saturated fat alternatives like olive oil or avocado oil. The final recommendation is to limit saturated fat, eat enough fiber, and recognize that outside of those priorities, seed oils are not a major health lever compared to bigger factors. Contextual data presented includes that average calorie consumption in the United States is 3,500 per day, with average physical activity below 20 minutes per day.

Full Transcript

Show transcript

Is there a precautionary principle? Uh
if someone says, "You know what, Lane,
I've heard everything you've said. I
can't poke holes in it, but it just
why should I go out and eat seed oils?"
You know, um what what would you say to
that person?
>> I would say, okay, if you don't want to
consume seed oils, fine, but find
something to displace the saturated fat
in your diet with. So, uh, leaner cuts
of proteins of meats, um, you know,
lower saturated fat sources of protein.
And I guess, you know, while
monounsaturated fats don't seem to have
the same effect on LDL cholesterol as
polyunsaturated fats, they do lower it
when exchange for saturated fats. And
um, they do appear to be cardoprotective
to a certain extent. doesn't appear to
be as cardioctive as polyunsaturated
fats. But if you are concerned and
you're not going to listen to logic that
we've laid out here for three hours, um,
okay, try and find some monounsaturated
fats like olive oil, um, avocado oil.
There there's other sources of oils that
you could use that are still relatively
cardiorotive or beneficial.
And the other thing I think I I should I
didn't point this out when talked about
the processing. It should be pointed out
that this is this is unique in that when
oil when these oils are in a large
volume that the rate of oxidation is low
even with heating right uh and by the
way all the heating in the processing
these oils is done under a vacuum which
means there's no oxygen which means v
virtually no chance for oxidation even
when heated.
In restaurants, however, when you are
frying something, especially if you are
frying in a thin layer of oil, the
research shows like going from like a I
want to say it's like a 1 cm to like 5
cm of oil,
huge difference in how quickly oxidized
and u negative products will start to
form. And if you are having oil that you
are frying, reffrying in over and over
and over, yes, they're within
certainly with a thin layer, within 20
30 minutes, you can start to have
significant amounts of these negative
products accumulating.
And then if you have it in a vat and
it's being heated all day, yeah, you're
probably going to have significant comp
amount of oxidized trans fats. So, would
we be better off when it comes to
heating oil using lard? In other words,
if I'm going to have French fries,
should I at least have my French fries
made in lard as opposed to
polyunsaturated fat and seed oil?
>> So, here's what I'd say. Both are bad,
right?
>> Okay, but let's just say I understand
that French fries are hyper caloric and
let's just put that aside. I'm going to
have French fries sometimes, right? So,
when I do, do I want McDonald's going
back to lard or do I want them sticking
with whatever seed oil they're using?
>> That's kind of a hard question to
answer, right? Because again, it's you
have competing mechanisms at play here.
And if we don't have a like a human RCT
looking at frying with one way versus
frying with another way, and I'm not
aware of any, but maybe there will be
some. Maybe a young potential scientist
listening to this would want to do this.
Um but looking at okay what happens with
LDL and then the components of LDL
>> but you're answering this purely through
an LDL lens. Right. Right. Right.
>> Yeah. Is is there any other reason to
care? There must I just it just feels to
me intuitively that at least when you
heat up the saturated fat you're not
you're less likely to introduce more
ROSS and other things. And by the way,
if I can control my LDL through other
means pharmacologically, do I really
care about my saturated fat consumption?
>> Good question. So, we'll we'll we'll
touch on that here in a second. So,
yeah, the saturated fats less prone to
oxidation. Again, when we're looking at
balance, what's going to have the the
what's going to negatively affect
cardiovascular disease the most? I I
don't know. Um, what I would say is this
really is probably if you're going to
have French fries, just have the French
fries. And if you want to have it fried
in lard, okay, fine. Whatever. You can
decide what you want to do.
>> But you're basically saying don't don't
treat my fries in in lard as health
food.
>> No. And I think I think that that's
actually a really important point you
bring up
is you have to understand people think
food companies care about which foods
you buy. They just want you to buy. And
so the the kind of the pivot to, oh,
we're gonna have tallow or lard or
whatever. Food companies don't care.
Okay. Well, we'll just make those then.
That's fine. Oh, you don't like red dye
40? Yeah, we'll take that out and then
we'll market about how healthy our our
cereal is now, right? Oh, we're
marketing how healthy our French fries
are. And so the the danger becomes, not
that again, I think I think this really
only becomes a problem if you're like
consuming French fries pretty regularly,
right? And then we have to ask the
question, all right, which is worse out
of these two really bad options.
But when you're marketing as some kind
of victory, then okay, we're we're using
beef tallow or using lard or whatever it
is as opposed to seed oils. If you're
not having this sort of communication,
people the what they what they are going
to interpret that as is, oh, these are
actually healthier now. And so I'm just
I can eat more of them. And so I think
that's one thing I've realized as a
being so in tune with the public and and
you know reading comments on social
media over years and years and years. I
realize how if I'm not extremely careful
with how I word things, how
misinterpreted it can get. And so I I
think as communicators,
like in a format like this,
this is great. And when you say like how
do people navigate on social media,
that's where it's really tough because
it's not this, right? It's 30 seconds.
How can I hook somebody in? Five reasons
why seed oils are toxic, right? Like
that's going to get a lot of attention.
And they're going to list things that
there is an element of truth to every
single thing that they say, but they are
leaving out all of the context that we
just put multiple hours into covering,
right? And who's [snorts] going to I
mean, I hope this podcast gets listened
to by, you know, hundreds of millions of
people, but the likelihood is pretty
unlikely, right? Um, what's more likely
is somebody puts up a Tik Tok and it
goes viral and 10 million people see it.
And so I think it's very difficult
to communicate this stuff with the
public when it to them there are so many
mixed messages, right? And Peter, I hear
this all the time where people say, you
know, I don't trust scientific research
because one study says this and one
study says that and they all contradict
each other. And what I say to people is
I say, "Did you actually read the study
or are you just looking at the social
media hottakes?" Because my guess is
you're probably looking at the hot takes
because what we just did going into
those studies when they seemingly have a
weird outcome,
I can tell you almost any time, 99% of
the time when I've seen a headline or a
social media hottake on a study that I
go, "That doesn't make sense." and then
I go and read the actual study.
99 times out of 100 I walk out going,
"Oh, okay. I see why they found what
they found." Right? Either the way the
control group was designed or um the the
difference in levels between groups or
or or whatever. My PhD adviser used to
say, "If I wanted to design a study to
show no effect or the study to show an
effect, easiest thing in the world." And
so again, this is why we look at
converging lines of evidence. We look at
what does all the evidence state and
what do the most high quality, most
rigorously controlled studies find. And
so
yes, there are elements of truth to the
criticisms of seed oils.
But on balance, when we look at these
hard outcomes, when we look at what we
are very sure we know to be true,
again, you can never I think one of the
things to point out in science, you can
never prove anything, right? Like we can
only disprove things, but we can have
relative degrees of confidence in
various data, right?
And
I would say
I have a relatively high degree of
confidence that apo containing
lipoproteins are aogenic based on
everything I've read, the converging
lines of data, especially the mandelian
randomization studies, especially the
statin trials.
I feel relatively confident about it.
Now, could I change my mind? Sure. But
it would take a lot of data over a long
period of time. Right now, you asked one
question I want to circle back to. Why
care about nutrition if you can just
control this with statins? Right. Or
Yeah. No, that that was in the context,
I think, of uh why care about the effect
on LDL if you can pharmacologically
regulate that anyway and therefore
should we be focused on other potential
negative health benefits in the case of
the frying? That was really my question.
>> Oh, I see what you're saying. So, so
let's take care of the LDL piece and
then now oxidation or or aldahhides or
whatnot become more important. That's a
>> it I was asking that specifically in the
context of the frying oils.
>> That makes sense. Yeah. and
[clears throat] cooking.
>> And so, yeah, I don't have a great
answer for that because like
I think one of the other frustrations
with the general public is
when we put out limitations of studies,
you know, you and I know like we're not
necessarily saying, "Hey, these
researchers are idiots. They did it
wrong. They should have done it this
way." Every study has limitations. every
single study that's ever been done in
the history of mankind. There is no
unifying study that explains the entire
universe. Right? So pointing out
limitations is not necessarily saying
that a study is bad. It's just pointing
out, okay, we got to be careful how much
interpretation we give to this, right?
How how broadly we interpret it. And
yes, there are studies that are more
well-designed, well conducted, that have
more statistical power, that are um that
have better measurements, and scientists
try to account for that when they look
at, okay, how much weight am I going to
give to something?
But
again, at the end of the day, if I have
to give a recommendation for people on
this stuff, I would say
when it comes to seed oils, if you don't
want to consume them, okay, I would just
say try to limit your saturated fat,
eat enough fiber, but outside of that,
there's so many bigger levers that you
can pull for your health than just
worrying about seed oils. You know, I I
put up a a thing a while back. I said
the average calorie consumption in the
United States is 3,500 calories per day,
and the average physical activity is
less than 20 minutes per day.
>> And you're spending all this time
worrying about what your fries get fried
in,
>> right? Not you specifically, but just
people in general, right?
>> It's like we're we're stepping over $100
bills picking up pennies, you know? And
so I again I'm not saying don't worry
about the little stuff but you got to
keep it in context of what really is
driving so much disease in the developed
countries. And a lot of it really is an
energy toxicity issue.
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