The Questionable Link Between Saturated Fat and Heart Disease | Hacker News Reader

The Questionable Link Between Saturated Fat and Heart Disease

on.wsj.com

42 pointsfhoxh58 comments

Wait a minute... I thought the notion that saturated fat caused heart disease was settled science. That we had a consensus. Now we realize we're wrong? That scientists cherry-picked data, had inadequate controls? That "too much institutional energy and research money had already been spent ... A bias in its favor had grown so strong that the idea just started to seem like common sense."

The tragedy is that after generations of blind, almost religious belief in flawed science those raised on a diet of synthetic fats, sugar, and refined flour are suffering obesity and diabetes like never before.

> Now we realize we're wrong?

Nope. "We" have realised that there's money to be made in selling contrarian diet books that tell people what they want to hear.

As opposed to selling "Healthy" fat free cookies, breads and meats laced with extra sugar?

I think the point of all this new research is that you can't take out fat and expect your diet to be healthy--the real story is much more complex. Most educated people would realize eating lowfat cookies still isn't a good habit to have, but society seems to think it's ok.

You're conflating two things.

"Eat less saturated fat" means ... eat less saturated fat.

Not: eat more of everything else.

And that advice is still sound. Calorie for calorie, gram for gram, saturated fat is worse for heart health than polyunsaturated fat.

You're blaming the scientists and doctors for being (somewhat wilfully) misunderstood. You might as well blame physicists for plane crashes. After all, they lied to us about gravity!

"In contrast to current recommendations, this systematic review found no evidence that saturated fat increases the risk of coronary disease, or that polyunsaturated fats have a cardioprotective effect."

http://www.nhs.uk/news/2014/03March/Pages/Saturated-fats-and...

As I noted below, that study was not focused on randomised controlled trials and has been criticised by sloppy work on the part of the authors.

I'm making a practical argument about the effects of "fat is bad" mentality. It is much harder to avoid sugar and nutritionally void processed food at this point in time.

Ultimately people want to be healthy, and using the heuristic to avoid fats isn't the way to make healthy eating decisions by itself.

Yes, because the whole "low-fat" movement is working so fine

Meanwhile in Europe they keep eating whatever they always ate (in moderation), not drinking soda, keep drinking (more moderately hopefully), and don't need a motorized cart to shop at a supermarket.

Even though it's hard to believe, I wouldn't doubt someone found out traditional Belgium fries (yes, in lard, yes, with a good amount of mayo on top) may end up being healthier than a lot of "low fat" crap in a supermarket

Both lard and the oils used in mayo are mostly unsaturated fats, by the way.

I agree with you about moderation, but the argument here isn't really about moderation.

It's about whether saturated fat is or is not distinguishably unhealthier than other sources of fat, once other factors (most importantly, obesity) are controlled for. The evidence from properly constructed studies suggest that it is.

For my own self, I know that red meat and saturated fat increase my risk of heart disease. But they are delicious, so I eat them -- in moderation. And I monitor and control other risk factors such as exercise and blood pressure.

The problem with red muscle meat is it has a good bit of trans-fats in it, and also excess of methionine and tryptophan relative to other amino acids (notably glycine). But the saturated fat is harmless. You can eat as much coconut oil as you want. Saturated fat is not the problem. Yet for the reasons above, eating too much muscle meat is to be avoided.

Obviously it's saturated fats. Actually, cholesterol. Make that LDL cholesterol. For clarification, LDL pattern B cholesterol. (Or was that just a marker for damage? I forget.)

The attitude of "settled science" is what kills science.

This is the same problem I have with the extreme push towards global warming mitigation.

Half a century ago we were worried sick about global cooling. Sure, we know more now than we did then. But that is not a valid response: in any decade we know more than in decades before that.

Most of the measures for global warming mitigation either directly cause massive economic costs (large taxes, etc, etc, which all end up preventing the same sort of progression that is allowing us to bootstrap!), are short-sighted (Carbon credits leading to old-growth forests being cut down), directly cause deaths (banning of CFCs leading to deaths due to the alternative puffer propellants not working as well), etc. Or end up as a combination of both.

For that matter: there are viking farms in what has been permafrost for the last ~500 years. We (assumption here) were not industrialized at the time. So: why was it not permafrost? And for that matter, considering the greenland ice sheet was not the size it is today at that time (again: assumption based on the fact that, you know, it wasn't permafrost at the time), why was the sea level not higher to the extent that people are predicting?

And the question is: for what gain? (For example: a large chunk of the Canadian shield, while good farmland, is primarily growing season limited. It seems plausible that higher temperatures could increase their yields. So: has anyone crunched the numbers? Plants grow better in higher CO2 concentrations. Etc.) And what alternative measures could be taken? (For example: dropping a nuke to trigger a volcano would lower global temperatures. We know this.)

It's my children's world that I'd like to build up here, and my children's children. I'd like to make rather sure that we know what we're doing. There is no rash decision quite like one affecting the entire globe for centuries.

It's not just about coal and oil's effect on global warming, but their effect on human health, too. The faster we move to cleaner technologies, the better. Wouldn't you like the children to grow in a healthier world?

The situations are different here. It's not like in 50 years we'll discover that "hey, wait a minute - inhaling coal fumes is actually good for us!" - which is what you're trying to imply with your comment.

"which is what you're trying to imply with your comment."

The grandparent comment said nothing whatsoever about air quality.

Notice: I did not mention air quality.

Notice: modern scrubbers are rather efficient

Not to mention that coal is one of those things that I am all for us getting rid of. But not to ban other countries from using. Spending 20-30 years bootstrapping themselves to alternative methods very well may be better than building up a massive population base because they couldn't get themselves to the point where birth rates drop.

Not to mention that half of the alternatives to coal have been EPA-d (is that a verb? Now it is) to the point where "dirty" fuels are the best option from a straight economic point of view.

A better example for your comment might be nuclear power. Where a large chunk of the reason behind why nuclear power is not more widely used is public (panicked) response to radiation concerns. Even though burning coal ends up with a larger radiation dose per MWH. Even though the alternative tends to be coal or oil fired power plants. Even though nuclear power (with suitable reprocessing) is the cleanest general-purpose form of power generation we have. (And yes, this includes "green" energy. Solar/wind require rare earth elements / batteries / etc, geothermal is highly regional, hydro causes issues with fish/etc, biomass is sooty, etc)

> "banning of CFCs"

CFCs were banned because they were destroying the ozone layer, and the ozone layer protects us from excessive UV-radiation (which causes skin cancer). This was not related to global warming.

Correct, sorry. I had forgotten that, although they are potent greenhouse gasses, that was not the reason they were originally banned.

Still a valid point in the "don't be rash" sense", but not in the "don't be rash regarding global warming" sense.

This is a canard. There was certainly some thought given to the idea of global cooling but there was never anything even close to the modern consensus about climate change (a term which recognizes the non-uniform effects of warming). http://en.wikipedia.org/wiki/Global_cooling

I get where you're coming from, but I do think you're being a touch disingenuous with questions like 'has anyone crunched the numbers?' Of course people have considered that higher CO2 concentrations could come with benefits as well as costs. Here's an optimistic crunching of the numbers, finding a $3.5 trillion benefit over the last 50 years, although I thinkt he methodology is severely flawed: http://www.co2science.org/education/reports/co2benefits/Mone...

And here are some explanations for why the relationship between CO2 availability and agricultural productivity is non-linear: https://www.skepticalscience.com/co2-plant-food.htm

I have to say that if you are as concerned about your descendants' future as you say, then I think it's time you did more of your own homework.

As for CFCs, the main problem I've been aware of resulting from the ban that might have resulted in deaths was due to the increased cost of asthma medication. Do you have any data to quanity how many deaths this has supposedly caused? Would you say that this is more or less than the lives that would otherwise be lost to skin cancer?

Just this week there was an article in Science about plants/soil as a CO2 buffer:

http://www.sciencemag.org/content/344/6183/508.abstract

> But that is not a valid response: in any decade we know more than in decades before that.

Why does the inevitable increase in accumulated knowledge imply that it doesn't make sense to base decisions on the current state of that knowledge? It sounds like you haven't thought this argument through.

Repeated, rapid fluctuations in the scientific opinion or lack of broad consensus would be warning signs, but neither of those are present.

> So: has anyone crunched the numbers?

Yes! That's what scientists do for a living. They publish detailed records of their data-->conclusion inference process, high-level scientific summaries of those individual results (reviews), and higher-level nonscientific summaries of their cause/impact/mitigation conclusions (IPCC reports). Thousands of them sign statements saying that their individual contributions weren't misrepresented in the high level reports, and then individual members of the community go forth and represent that consensus to the media and to politicians.

And then people like you notice that their soundbytes don't constitute a formal inference process and use this fact to argue that the scientists don't know what they're talking about. Of course, you're too damn lazy to dig through their painstakingly constructed pyramid of results and see for yourself, so you have to keep your feet firmly planted in "my ignorance is as good as your knowledge" territory to keep up the argument. This should tell you something.

> Plants grow better in higher CO2 concentrations.

Do you really think this escaped the notice of thousands of specialists with millenia of accumulated experience?

Answer: it didn't. Here's the latest report I've seen addressing this issue. There have been plenty of other reports answering permutations of this question, but they weren't published last week in Science, so I'd have to use google scholar to find them.

http://www.sciencemag.org/content/344/6183/508.abstract

> I'd like to make rather sure that we know what we're doing.

"Doing nothing" is doing something -- something that the only people in a position to make credible predictions regarding the effects of what we're doing are awfully worried about.

> dropping a nuke to trigger a volcano would lower global temperatures. We know this.

You seem far more confident in your ability to predict the climactic effects of a nuke in a volcano than in the scientific community's ability to predict what happens when we dump an insane amount of CO2 into the atmosphere. Why?

A child could tell you why the volcano would be a bad idea. I'm quite certain you've not given this nearly as much honest thought as you think you have.

> raised on a diet of synthetic fats, sugar

The anti-sugar hysteria a la Lustig is the other shoe to drop. The fear mongering is a bunch of baloney when you look into it.

The anti-sugar "hysteria" stems from the fact that everything seems to have some type of sugar added to it.

If you live in USA you probably have too much sugar in your diet if you're not taking any steps to reduce it. When my wife(and her mom) first came to USA from Nigeria, they both complained that everything tasted like sugar. Even dinner-type meals that are suppose to be savory. I also have a relative who doesn't need their medication to control their blood-sugar when they're in Nigeria instead of America.

Also, on my own quest[1] to be healthy and reduce my weight everything ultimately came down to reducing carbs and sugar in my diet. Lost nearly 40 lbs. People always say I look much younger than my age and I have trouble getting into Nightclubs sometimes since I don't look like my driver-license picture anymore.

1. http://smtddr.hatenablog.com/entry/2011/06/19/Wii_Fit_Plus%3...

> "That scientists cherry-picked data, had inadequate controls?"

The type of people who end up (or even aim for) in government regulatory bodies, are usually not the cream of the cream of scientists.

In Greg Egan's story Crystal Nights, one of the characters became rich by making a site called "FoodExcuses.com", where you input what you eat and it gathers all of the scientific literature justifying it as a healthy diet.

It's just a throwaway joke in the story but I'm convinced it would absolutely work in real life.

http://ttapress.com/553/crystal-nights-by-greg-egan/

Every day I find more evidence that the internet mainly serves to confirm for people what they already believe. Just like I always suspected.

I accidentally downvoted you, but this is very clever.

Ha :)

Seriously, this is a worry. When I was younger I thought the Internet would make the scientific method go mainstream, with Usenet and later the web functioning as a sort of intellectual meritocracy.

Note to idealists: expect less and you won't be disappointed.

I'm an optimist and think it works a bit. Amongst all the rubbish there's some well thought out stuff out there on the interwebs and those that are interested may be able to find it. The people who like reading nonsense for entertainment don't matter that much. Except they vote. So maybe they do. Anyway...

The most recent research still upholds that saturated fats, over and above their contribution to obesity, are a worse risk than polyunsaturated fats.

A meta-analysis of 8 randomised controlled trials with 13 thousand subjects showed that a 5% total energy substitution from saturated to polyunsaturated fats reduced risk of coronary heart disease by 10%.[1]

The point about substituting hydrogenated fats is good; but it's hardly an argument for switching back to saturated fat. It's an argument in favour of not eating unhealthy food in the first place.

But that's not how you sell books, is it?

[1] http://www.ncbi.nlm.nih.gov/pubmed/20351774/

A meta analysis of 80 studies involving more than a half million people found no evidence of dangers from saturated fat, or benefits from other kinds of polyunsaturated fats (excluding trans fats, which were shown to be terrible)[1].

[1] http://well.blogs.nytimes.com/2014/03/17/study-questions-fat...

That meta-analysis was not based on randomised controlled trials. It was largely based on observational and self-reporting studies, which are notoriously inaccurate.

Moreover, it was subject to numerous corrections due to sloppy work by the authors:

http://news.sciencemag.org/health/2014/03/scientists-fix-err...

Thanks, hadn't seen this link. I'd like to see the specifics of what the errors are. Agree that observational and self-reporting are inaccurate, though unfortunately they're some of the best data we've got wrt nutrition.

Also, looks like there were some random trials in the meta analysis. From your link:

"These included trials in which participants were randomly assigned to different diets, as well as observational studies in which participants' intake of fatty acids was determined by asking them about their diet or by measuring the fatty acids circulating in the bloodstream."

> Also, looks like there were some random trials in the meta analysis.

There were, but the statistical effect is drowned by the much larger pool of observational/self-reporting studies.

Observational studies are a useful place to find potential leads, but they are nowhere near as reliable as RCTs for many reasons. Observational studies can tell you that the fall in piracy is causing global warming. Short of a randomised controlled trial involving the introduction of pirates or non-pirates at random to 13,000 Earth-like planets, it's hard to know how strongly that relationship holds.

I agree with you about observational studies when I wrote in the grandparent:

> Agree that observational and self-reporting are inaccurate, though unfortunately they're some of the best data we've got wrt nutrition.

They are not the best data. It's just too widely used.

excellent point.

What if there are other diseases beside heart disease that might be helped by consuming saturated fats?

Then people with those diseases should follow the advice of their doctor and/or a registered dietitian. The rest of us live in middle-of-the-curve land, where vengeful sigmas kill more people from heart disease than almost everything else.

Good

What about only reducing saturated fats by 5% (replacing it with carbs, or something else?) and maintaining PUFA levels?

What about adding the PUFAs, maintaining SFAs and reducing caloric intake somewhere else?

Consumption of PUFAs have a known effect on cardiac health, so the result of this work is 1) not surprising 2) saying nothing about SFAs (what about diets with different levels of SFAs and no difference in PUFAs?)

The trouble with those sorts of studies is that they don't prove much - only that there's a weak correlation between thing A and thing B which is a good starting point for research but poor evidence for drawing conclusions from in itself. To follow up a scientist might say - ok lets look as people who eat basically nothing but saturated fat and people who eat basically none and see if one group drops dead quicker. This has been done, for example traditional eskimos live basically on saturated fat from the seal like stuff they eat and their health is fine. On the other hand some stuff like man made trans fats do kill you in a measurable manner - use them as your main diet and you'll drop some years earlier which is why they are being banned - eventually after many years of such evidence. The human body is pretty adaptable and can live OK on most foods that we have evolved with so switching from nuts to meat will probably not have a dramatic effect on life span as the body can deal ok with both on the whole.

I've followed the Paleo diet for over two years now and the health benefits have been great for me (an incidental part of eating tons of meat is getting a good amount of animal-based saturated fat).

After many discussions with many people about what is or is not healthy and a lot of reading, I've come to believe two things:

1. We (scientific and non-scientific community) have no clue what is or is not healthy, and it probably varies from person to person, and

2. The human body is really good at giving indicators as to whether or not it is healthy. With a bit of experimentation (food/exercise) and attention to physical and mental well-being it's not hard to assess one's health.

The difference for me after going Paleo was noticeable after about two weeks -- improved memory, energy, happiness, sleep, lots of other stuff. I've heard similar stories from others that have become vegan, vegetarian, discovered high-FODMAP insensitivity, etc.

Shameless self-promotion: I built http://www.fitsmeapp.com to help find food (currently just recipes) based on arbitrary user-defined "diets". Feedback is always appreciated.

Going by how you feel in response to diet changes doesn't necessarily work all that great. Eating loads of meat and under consuming sugar and starch, for example, will send catecholamine levels way up. This will have the short term affect of making you feel better. Inflammation will go down and you'll have more energy. This is the same effect that causes people to say they feel good on a fast. But once you clock up a year or two with elevated catecholamines your health will tank from the stress.

It's been two years. Health is great, stress is largely non-existent. I guess I'll have to wait and see.

Can I ask what you have in your Paleo diet? Because I once witnessed some one mention 'Paleo Cookies' which is completely ridiculous which led me to believe it was a fad die that went along with Crossfit.

Sure -- assuming you mean personally:

Any meat, any vegetables, decent amount of fruit, any kind of potatoes, butter, some nuts. It's a bit of a deviation from the by-the-book version (whatever that actually is -- it varies depending on who you talk to) because of potatoes and butter.

People will make "Paleo Cookies" and other baked goods usually with a combination of nut-flours, potato starch/flour and honey for sweetener (among other things). They tend to look ugly and taste pretty bad. Not to mention contain lots of sugar (which, even if it's honey, ends up defeating the purpose proportional to how cookie-like you want it to taste). I have made things like that though -- cookie cravings happen.

If you mean in Fitsme:

We have something fairly close to what's probably mentioned by Crossfit -- but it's 100% configurable, so it can have whatever you want it to.

I don't think i know anything anymore.

Admitting ignorance is better than repetition of unfounded "common wisdom". Disbelief in one's own understanding of something is the first step towards developing a better understanding of something.

Socrates would approve.

Study Questions Fat Heart Disease Link http://well.blogs.nytimes.com/2014/03/17/study-questions-fat...

A Lifelong Fight Against Trans Fats http://www.nytimes.com/2013/12/17/health/a-lifelong-fight-ag...

The Oiling of America https://www.youtube.com/watch?v=fvKdYUCUca8

I really want this to be true.

I would just like to point out that earlier[1] there was a discussion around science not showing any evidence of GMO harm. We don't have a complete understanding of nutrition and the human body; and there's a lot of money to be made making everyone believe one thing or another. Anyone who thinks they have it "all figured out" is setting themselves up for a surprise.

Even I admit that my chasing of labels such as Non-GMO and USDA Organic could also be a big marketing scam and they could very well be selling me the same pesticide-soaked, GMO-glued-together, sweetener-laced, antibiotic+steroids pumped food that everyone else is buying while charging me a 40% markup for a lie. But since I'm confident we're all just rolling dice here, I choose to gamble on chasing food that's supposedly very similar to what my family has been getting it for generations in Nigeria with no particularly notable health issues except 2 instances of diabetes. One of them came to America, started eating all the common fast foods, drinking, smoking, etc for over a decade. The other is related to depression and change of eating habits while still in Nigeria.

If I'm wrong... I'm wrong. But I hope this lets people know that our current science(and social/economical incentives around it) is not good enough to use as a debate-closer of health & fitness discussions. There are contradictions[2][3] out there. I suspect that at the end of the day, what's good for one person can be poison for another and all our attempts at generalizing health & fitness guidelines for everyone will ultimate end in failure. We'll all have to go into the hospital, get a DNA sample and get customized health & fitness advice - and that's assuming we can remove the economic incentives for hospitals/doctors to just tell us whatever it takes to sell some expensive "solution".

1. https://news.ycombinator.com/item?id=7671699

2. "Many of the bacteria are species that the researchers had never seen before. And even familiar microbes were present in unusual levels in the Hadza belly. “The Hadza not only lack the ‘healthy bacteria,’ and they don’t suffer from the diseases we suffer from, but they also have high levels of bacteria that are associated with disease,” Crittenden said." ---- http://www.wired.com/2014/04/hadza-hunter-gatherer-gut-micro...

3. " Unlike their Western counterparts, the Tarahumara don't replenish their bodies with electrolyte-rich sports drinks. They don't rebuild between workouts with protein bars; in fact, they barely eat any protein at all, living on little more than ground corn spiced up by their favourite delicacy, barbecued mouse. ---- http://www.dailymail.co.uk/home/moslive/article-1170253/The-...

Have we become stupid to the point that we need the Internet to tell us what to eat? What were we eating for millenia before we invented nutrition experts? Is this article of relevance/interest to HN?

Diet matters. There are good scientifically informed choices that can reduce your risk of horrible diseases like cancer and alzheimers.

Even in the context of traditional diets there are good ones and bad ones.

Do you want to look like this guy: http://www.kimmacquarrie.com/wp-content/uploads/2012/07/Mash...

Or this guy: http://1.bp.blogspot.com/-rTRD-USWhSk/UTIwrhmGFcI/AAAAAAAAAT...

They both eat traditional diets, clearly with very different physiological outcomes.

Your making the assumption that because one guy is skinny he is healthier than the other. The 2nd picture (Darker Skinned) is a Maasai Warrior and the other are Mascho Piro. They will probably have different diets and do differencing amounts of exercise daily, but just because one is thin and one is not as thin, doesn't say anything about health.

Both look healthy to me ;) The problem is that since we do not have the means to conduct the scientific experiments ourselves we rely on experts and public agencies. Hard to tell if either is working unbiased. So, in lack of certainty and trust, I rather just eat as my grandparents did. So far so good!

I find it fascinating that:

The very cornerstone of dietary advice for generations..."

...is being challenged because:

Critics have pointed out that Dr. Keys violated several basic scientific norms in his study.

It's a cautionary tale worth telling no matter the discipline. Studies are often accepted without much challenge because we assume that rigorous controls were in place. But the adage of "Garbage in, garbage out" remains a fundamental truth. I think that is what is relevant and interesting to HN readers.

Corporate advertising and marketing to a large extent. As an example a traditional breakfast might have been porridge or some bread or eggs. The the like of Kellogg's came along and I grew up with "Frosties - they are great" on TV all the time. Large heaps of carbs with sugar all over them are not healthy. The UK government wanted to ban advertising junk to kids but Kellogg's who spend ~us$100 million a year on ads here freaked out and hired lobbyists and the government backed down. So we need the internet to counter this. I don't know if this article is of relevance to HN. I find it quite interesting.

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