Do dietary cholesterol and saturated fat cause heart disease? | Ronald Krauss
Do dietary cholesterol and saturated fat cause heart disease? | Ronald Krauss
Most of the cholesterol in our body is made by the body itself and minimally influenced by the cholesterol we eat. The recommendation to limit dietary cholesterol to less than 300 milligrams per a day was not backed by quality research and is no longer recommended. In addition, saturated fat increases large LDL, but not the more harmful small LDL. As a result, there is little evidence to support the theory that saturated fat increases heart disease risk. Dr. Krauss believes that the foods in which the nutrients are consumed are more important than the nutrients themselves. For example while saturated fat alone is not strongly associated with heart disease risk, red meat is high in saturated fat and has been strongly associated with heart disease risk. In this clip, Dr. Ronald Krauss debunks common myths of dietary cholesterol and saturated fat.
This clip was taken from the FoundMyFitness interview with Ronald Krauss found at • Dr. Ronald Krauss on LDL Cholesterol,…
Original episode published on Oct 16, 2015
❤️ #cholesterol #heartdisease #diet 🍽
Content
0.099 -> [Rhonda]: You mentioned earlier that we produce
cholesterol in our cells, we're making cholesterol
6.04 -> ourselves.
7.3 -> And I think that most people think about cholesterol
in their body as originating from the food
13.08 -> they eat.
14.08 -> They think, for example, if they eat an egg,
a yolk, which is high in cholesterol, if they
19.07 -> eat six of those eggs, then their blood cholesterol
is going to go up, but that's not necessarily
23.73 -> true.
24.73 -> Can you explain?
25.73 -> [Ron]: So one of my multiple lives has been
in the world of nutrition, and, early on,
31.35 -> I've been interested in nutrition virtually
all my life and really came into lipoprotein
38.499 -> research because I had felt that diet had
a very important role in heart disease, and
42.93 -> the lipoprotein effects of diet, I thought,
were really important.
47.489 -> And I've been studying that now for a long
time.
49.469 -> And so I became involved, not just on the
research side of things, but also more on
55.87 -> the public health side through my work with
the American Heart Association, I became chairman
59.519 -> of the nutrition committee quite a few years
ago now.
63.309 -> And I remember that committee, which has now
morphed into a larger organization that I
71.97 -> helped to establish within the AHA, so I've
been an important part of the American Heart
75.859 -> Association's messaging to the public.
77.539 -> [Rhonda]: You're involved in the dietary guidelines,
right?
79.77 -> [Ron]: Yeah, from the American Heart Association,
I've actually did that twice.
83.35 -> And so I was forced to sort of deal with translating
the science, such as it is, about diet and
90.27 -> heart disease risk into something that could
be actionable.
93.06 -> And that's tough because the data linking
diet to heart disease risk through any mechanism,
100.429 -> lipids or otherwise, really doesn't necessarily
establish a causal role because there's so
106.691 -> many features in diet.
108.149 -> You can't just easily pick one thing or another.
111.049 -> But cholesterol was on the radar screen.
112.549 -> So, when I became chairman of the nutrition
committee on my first cycle, there was a lot
117.28 -> of media.
118.28 -> I spent a lot of my time dealing with the
media, and I was just astonished by the questions
124.85 -> I would get about dietary cholesterol, blood
cholesterol, and, as we say, people just conflated
131.75 -> those two terms.
133.52 -> And I've spent a considerable portion of my
time trying to educate, like, the so-called
137.99 -> science...well, the science writers who are
often not trained in science at all, actually,
142.71 -> I'm sorry if I offended anyone.
145.3 -> But they are trying to understand this and
they just simplify this right to the point
148.89 -> where it becomes totally meaningless.
152.3 -> The body makes cholesterol.
153.6 -> It regulates the absorption of cholesterol
from foods.
156.13 -> And the contribution of dietary cholesterol
on blood cholesterol, I was actually forced
160.1 -> to address this in a very rigorous way through
a committee that I was on for the Institute
165.641 -> of Medicine of the National Academy of Sciences,
which established dietary recommendations
169.82 -> for macronutrients, which it was the first
time that anybody really did that seriously.
174.12 -> So we produced this enormous volume.
175.54 -> We had a committee looking at every aspect
of macronutrients and health.
181.01 -> And my topic, which I had to take on, was
cholesterol, dietary cholesterol.
185.97 -> And when I went through the literature, I
was just astonished that how small the effect
189.65 -> is, and it's very difficult to even imagine
how an effect of excess dietary cholesterol
196.12 -> couldn't influence heart disease risk unless
when you either had a mutation that caused
202.37 -> the cholesterol to build up, or when receiving
an enormous amount of dietary cholesterol.
208.45 -> But for the most part, the effect was so small
that it was almost unmeasurable.
212.8 -> So we wrote that report and I'd sort of made
that point.
217.01 -> And then 15 years later, the current dietary
guidelines come out saying, "After all these
221.35 -> years of recommending keeping cholesterol
less than 300 milligrams per day, we realized
225.17 -> that we no had data to support that."
226.95 -> And so it took a long time for the U.S. dietary
guidelines to catch up, and I was really in
233.06 -> a bind because there was this historical precedent
of limiting dietary cholesterol because of
238.72 -> its potential role in blood cholesterol levels.
241.32 -> And it's really not even worth talking about.
245 -> [Rhonda]: But the idea is still out there,
and physicians still even recommend not eating
249.1 -> eggs.
250.1 -> [Ron]: I know.
251.1 -> Yeah.
252.1 -> So eggs is in a whole, another story.
253.1 -> And so, again, when it moves from dietary
components to the food that those components
256.799 -> are contained in, which was really one of
the messages that I've tried to emphasize
260.65 -> in all the work that we've done, trying to
reach the public, which is, again, a nice
265.42 -> opportunity here for me to do this with you,
is that we should be thinking about the overall
271.69 -> context in which those nutrients are adjusted,
foods and dietary patterns.
276.29 -> And finally, the U.S. dietary guidelines are
beginning to think about dietary patterns
280.07 -> rather than just individual nutrients.
281.96 -> However, they still have not abandoned focus
on measuring this or that fatty-acid.
288.72 -> We should be thinking more about the overall
food context.
293.22 -> And the important regulators of heart disease
risk from a dietary standpoint go way beyond
302.03 -> the effects on blood cholesterol.
303.38 -> And we have to think of a lot more complexity
in the role of diet, not that cholesterol
310.49 -> and lipoprotein effects aren't important.
312.5 -> In here, we can point to saturated fatty acids,
for example, we can have a discussion about
316.88 -> that if you wish, raising blood LDL levels.
320.76 -> Does that translate into higher heart disease
risk?
326.4 -> Well, it's very hard to show that.
328.81 -> In fact, there's almost no evidence to support
that relationship.
333.04 -> And parenthetically and maybe importantly,
we've shown that the form of LDL that increases
341.06 -> with saturated fat is not the small LDL, but
the large LDL.
344.33 -> And in fact, that led me to question whether
or not saturated fat was really an important
350.24 -> factor in heart disease risk because our studies
did not show that it was increasing small
354.09 -> LDL in the majority of the population.
356.08 -> Maybe there are individuals who are hyper-responders
who probably ought to stay away from saturated
361.75 -> fat, but for the general population, I began
to suspect that this relationship was not
367.4 -> as strong as people thought because it was
the less dangerous form of LDL that was increased
373.15 -> by saturated fat.
374.461 -> In fact, that's what we showed.
375.461 -> And I have gotten involved now in a lot of...
377.61 -> I've taken a lot of heat for that.
379.67 -> But as time has gone on, we first published
this with Dr. Siri-Tarino, in my group, about
387.94 -> five years ago now, and we were really hit
hard when we published that first paper questioning
395.93 -> the relationship between saturated fat to
heart disease risk.
399.16 -> I'm glad to say that, over the last year or
two, there have been a number of reports that
404.49 -> have supported that absence of the strong
relationship.
411.07 -> And the LDL part of the story, I think, may
be part of the reason for that, but there
414.09 -> may be other factors, as well.
415.55 -> Again, it may not be the saturated fat itself
that should be incriminated here, it should
421.11 -> be the foods in which that is consumed.
423.29 -> And there may be, for example, in fact, there
is evidence from epidemiology that red meat,
429.15 -> particularly processed red meat, which contains
saturated fat, may have adverse effects on
434.54 -> heart disease as well as life itself, life
expectancy, and other diseases, and it may
442.49 -> not be the saturated fat that's the most important
factor there.
446.06 -> We don't know.
Source: https://www.youtube.com/watch?v=Nj8yFPc2qfo