Is the "lipid hypothesis" all hogwash?

My wife recently watched a documentary (“Fat Head,” if you’re interested) which makes the claim that, despite consensus support, the “lipid hypothesis” (ie high cholesterol causes cardiovascular heart disease) has very little clinical support. It initially struck me as another fringe-y theory, and the documentary wasn’t particularly convincing to me.

But I did a little more digging out of curiosity, and it’s got me a little curious. It sounds like quite a few of the folks saying it’s crap have solid credentials and understand the concepts of medical research well. Their argument is basically that the clinical evidence for the lipid hypothesis is very weak and that it’s become consensus through the non-scientific avenues of “making a whole lot of sense on paper” and a government panel cherry-picking evidence because it was headed by folks who bought into a woo diet popular at the time.

It’s hardly convincing, but I haven’t seen much in the way of good rebuttals.

Being far from an expert on any of the involved elements, I thought I’d put the question out there: should I trade my morning oats for a slab of bacon?

Like who? I watched it and IIRC, those experts were folks from the Weston A. Price Foundation and Kevin Trudeau.

The doc makes mention that the head of a government center for nutrition or science or something or other was one of the dissentors who was ignored.

The others in the doc seemed wishy-wishy, but my random googlin’ suggested a fair few MDs and otherwise credentialed folks. The honest truth is that, lacking specialized knowledge, I’m not in a position to analyze credentials well.

How about doing a search here on the Dope?
Let’s talk about Dr. Weston A. Price and his theories or any of several on Trudeau, like Help me convince my father that Kevin Trudeau is a lying bag of horseshit

Or just Google Weston A. Price quack or Kevin Trudeau quack.

It doesn’t matter if they claim that the sun comes up in the east. If you see their names head for the sunrise in the west.

With luck Jackmannii will be here to say the same thing in rational scientific language.

That’s getting off the track: I’m aware there’s quackery on the “natural foods” folks. I also don’t recall Fat Head mentioning Trudeau or Price; if the folks interviewed were connected, I didn’t notice the connection. I’ll admit I was paying 2/3s attention.

My question is: is there good science supporting the lipid hypothesis?

I did do a search on these very boards, and found several people stating the evidence is poor, but it seemed to generally be an aside, not the focus.

Look under “Scientific consensus” in the following wiki article.

http://en.wikipedia.org/wiki/Lipid_hypothesis

Yep, I have: it indicates that a lot of doctors said they think it’s true in a survey, suggests that there’s good research, and points out that there are critics saying the research is poor.

That’s why I’m asking.

No, it doesn’t; it answers your question.

It doesn’t say “a lot of doctors said they think it’s true in a survey”; it says,

*"The National Institute of Health held a consensus development conference reviewing the scientific evidence in 1984, during which a panel of 14 experts unanimously voted “yes” on the questions of whether blood cholesterol was causal and whether reducing it would help to prevent heart disease.[10] The panel concluded:

It has been established beyond a reasonable doubt that lowering definitely elevated blood cholesterol levels (specifically, blood levels of low-density lipoprotein (LDL) cholesterol) will reduce the risk of heart attacks caused by coronary heart disease..."*

Did you look at the footnotes?




Apologies for being flip. The footnotes certainly suggest there’s research out there.

I suppose my real question should be this: if folks like THINCS (http://www.thincs.org/) are quacks, is there any good rebuttal or refutation out there? I’ll admit I’m having trouble entirely finding out what the allegations of these guys are – but that’s not because they’re cagey. Uffe Ravnskov has written multiple books on the subject, but I’m not seeing his specific allegations in doing a cursory glance.

Understand, I’m not trying to defend this position – I’m just curious and my usual anti-woo, anti-bullshit skeptic bells aren’t quite dinging yet.

Here’s a start:

I haven’t heard of any of these quacks, rather, my impression was that the history of research was:

in the 60s, doctors found that a lot of heart infarct patients had high cholerstol and arteriosclerosis, and so that one caused the other caused the third. This sounded plausible and was borne out by the current data collected. So doctors started recommending patients to lower their cholerostol, and give medication if necessary to that effect.

Sometime in the 80s, scientists discovered that cholerostol could be differentiated into High (Hdl) and Low- (LDL) cholerstol, and that one was the “bad” stuff causing arteriosclerosis, and the other one the “good” stuff that helped your body. So now the recommendation was to lower your bad cholerstol and increase your good cholerstol, meaning that all food had to be measured again.

Then a bit later, a new study looked at the rates of cholerstol and arteriosclerosis among a big number of people, and to the surprise of the researchers, while most with arteriosclerios also had high cholersterol, a lot with high cholerstol didn’t have arteriosclerios.
Together with some troubling side effects of common cholerstol, and the fact that 75% of cholerostol is produced by the body itself, not from food, because cholerstol is a building block of many body-produced compounds, doctors stopped forbidding the daily breakfast egg as bad, and stopped prescribing cholerstol -blockers in all cases, instead looking at other health indicators additionally.

My impression of the current consensus is that some people are likely to get arteriosclerosis from high cholerstol, but not all - obviously depending on the genetic makeup. The general recommendation is not so much to take blockers, but to live healthy by not eating as much “bad” fat and getting a lot of exercise.

This is similar to my impression of the relationship between salt intake and high blood pressure, that for some people, but not all, it’s a concern. It appears to me the medical profession is unable or unwilling to sort out who would be harmed from these substances from who would not, and defaults to “better safe than sorry” blanket recommendations for everyone to limit their salt intake and keep their cholesterol levels down.

One alternate theory is that arteriosclerosis is the result of a chronic low-grade infection with Chlamydia Pneumoniae.

Hm, sounds like my gut instinct was about right. Funny how often “the truth’s in the middle” seems to shake out…

I think the problem with theories about human biology is that it’s really hard to test any hypothesis, because you can’t just go experimenting on human bodies. Serious, controlled experiments are difficult and very expensive to conduct. So we tend to place a lot of emphasis on the relatively small number of seemingly respectable trials that have been conducted. But I think the truth is that we are still in the dark ages in this area. We simply don’t know what has caused the apparent increase in heart disease, obesity, and other so-called diseases of civilisation.

Cholesterol, or certain types of cholesterol, may be a risk factor in heart disease, but the term “risk factor” can be misleading. All it means is that there is a correlation, not necessarily a cause. Cholesterol seems to be associated with heart disease, but is not known to cause it, no more than the presence of firemen is known to cause fires, despite being strongly associated with them (to use one of the sceptics’ favourite illustrations). It could be that something else causes heart disease, and cholesterol levels rise in order to combat it. If that is the case, then artficially reducing cholesterol is the last thing we should be doing.

It’s complete horseshit. See Gary Taubes’ Good Calories Bad Calories for an overview.

Also see these previous threads:

My memory is getting pretty awful, but I thought that Gary Taubes wrote that it was beginning to appear as though the culprit was a lipoprotein which transports LDL cholesterol. Yes, here is an article he wrote for the NY Times about cholesterol which describes it and the cholesterol/heart disease questions. It’s a couple years old now, though, so there could be more current answers.

I have have spent years reading the available research and discussion, and am inclined to think that the lipid hypothesis (which is not based on any solid evidence at all!) is total hogwash - dangerous hogwash. There is so much we don’t understand about the human body yet, so much more research to be done before we have the answers.

I do feel certain enough that ‘aretery clogging saturated fat!!’ isn’t harmful to health that I eat something like 100g of it per day. :slight_smile: I had an excellent lipid panel before and after I started doing this, so I’m worry-free.

Hogwash? Most certainly not. As completely settled of a question as it is often made out to be? No.

High LDL cholesterol is certainly associated with increased risk of heart disease and there is proven measurable benefit in terms of lowering the rate of death from heart disease when LDL cholesterol is lowered with certain statins. Controversy exists, as discussed in this article about a recent Cochrane review, as whether the benefit is big enough to justify their use in lower risk individuals. But the debate there is not if there is an effect, just how big and if the benefit justifies the societal cost for those at relatively lower risk.

It is not completely clear that the effect is directly attributable to the cholesterol lowering however; correlation is not causation. Indeed it may work more through some other effect, such as an anti-inflammatory one.

Unfortunately performing studies that actually look at mortality as the outcome are very expensive to do, as they require very large subject pools, so many studies use surrogate outcomes, which limit the strength of the data.

The evidence for dietary changes as a means to reduce heart disease mortality is also not quite as iron clad, or at least as dramatic, as it is often portrayed. That may be because people rarely succeed in keeping up with dietary changes, some that the advice may have been a bit off target (historically replacing saturated fats with polyunsaturated ones and carbohydrates, which in some cases have been even worse. OTOH diets fairly low in saturated fats, simple carbs, and highly processed foods (salts and nitrates), and higher in whole grains, nuts, legumes, fish, and lean meats, is associated with good health outcomes whatever the actual mechanism and statins beneficial effects are real whether or not it mainly attributable to its hypocholesterolemic effects or not.

More research regarding the Lipid Hypothesis:

http://www.unboundmedicine.com/medline/ebm/record/18609049/abstract/End_of_the_road_for_the_diet_heart_theory

http://jech.bmj.com/content/33/2/114.abstract