15 replies to this topic

[oehaut]

Alright. I'm new here and this forum is awesome. I've learn a bunch of very interesting things lately.

I've read about every subject I found interesting in the 19 pages of the nutrition threads, and many people here are pretty sure that saturated fat are bad.

I'm always looking for stronger arguments in favor of an idea (i'm trying as much as possible to be evidence-based) and so far i'm not convince about the harmfulness of SFAs.

Things can always change tho. I'm truely reconsidering my high-protein diet right now with everything i've read here.

That being said, I was thinking it would be a great thing to have a review of the controlled trial involving SFA modulation and CVD and total mortality outcome.

I'm starting my MSC in nutritional science this junary so i'm soon gonna be able to properly interpret a study with good research statistic skills. Right now, I gotta read paper and try to understand as much as I can, and obviously I rely upon others people thoughts a lot.

So, with this in mind, I don't feel like I can properly review the evidence myself. I've got all the papers on my PC so I can only corroborate what I read else where.

SO, that pretty long introduction leads us here : Saturated Fat and Health: a Brief Literature Review, Part II

I feel like Stephen from Whole Heart Source is one of the best blogger out there. I pretty much like this review because it goes straigth to the point.

Anthony Colpo in his Great Cholesterol Con's book did a very good job a reviewing the evidence too, but it's not available online.

What i'd like is that people read this post and comments on it. It's a pretty short read.

Here's the main point :

Out of 12 trials:

* Two trials found that replacing saturated animal fat with polyunsaturated vegetable fat decreased total mortality.
* Two trials found that replacing saturated animal fat with polyunsaturated vegetable fat increased total mortality.
* Eight trials found that reducing saturated fat had no effect on total mortality.

I know there's a lot of observationnal study out there, but since we have a bunch of controlled trial to rely upon, i'm not sure how much these observationnal study add to this. And anyone who have read Colpo's book will also know that the vast majority of prospective trial have not found any benefits of cutting down SFAs.

I'm really looking to have my current thinking challenge; i'm all open to change my mind if the evidence are telling me to do so.

So, is Stephan wrong here?

What evidence would make a good case against SFAs if most of the controlled trial didn't find any benefits from cutting it down?

[HaloTeK]

Alright. I'm new here and this forum is awesome. I've learn a bunch of very interesting things lately.

I've read about every subject I found interesting in the 19 pages of the nutrition threads, and many people here are pretty sure that saturated fat are bad.

I'm always looking for stronger arguments in favor of an idea (i'm trying as much as possible to be evidence-based) and so far i'm not convince about the harmfulness of SFAs.

Things can always change tho. I'm truely reconsidering my high-protein diet right now with everything i've read here.

That being said, I was thinking it would be a great thing to have a review of the controlled trial involving SFA modulation and CVD and total mortality outcome.

I'm starting my MSC in nutritional science this junary so i'm soon gonna be able to properly interpret a study with good research statistic skills. Right now, I gotta read paper and try to understand as much as I can, and obviously I rely upon others people thoughts a lot.

So, with this in mind, I don't feel like I can properly review the evidence myself. I've got all the papers on my PC so I can only corroborate what I read else where.

SO, that pretty long introduction leads us here : Saturated Fat and Health: a Brief Literature Review, Part II

I feel like Stephen from Whole Heart Source is one of the best blogger out there. I pretty much like this review because it goes straigth to the point.

Anthony Colpo in his Great Cholesterol Con's book did a very good job a reviewing the evidence too, but it's not available online.

What i'd like is that people read this post and comments on it. It's a pretty short read.

Here's the main point :

Out of 12 trials:

* Two trials found that replacing saturated animal fat with polyunsaturated vegetable fat decreased total mortality.
* Two trials found that replacing saturated animal fat with polyunsaturated vegetable fat increased total mortality.
* Eight trials found that reducing saturated fat had no effect on total mortality.

I know there's a lot of observationnal study out there, but since we have a bunch of controlled trial to rely upon, i'm not sure how much these observationnal study add to this. And anyone who have read Colpo's book will also know that the vast majority of prospective trial have not found any benefits of cutting down SFAs.

I'm really looking to have my current thinking challenge; i'm all open to change my mind if the evidence are telling me to do so.

So, is Stephan wrong here?

What evidence would make a good case against SFAs if most of the controlled trial didn't find any benefits from cutting it down?

Too many people here have an all or nothing philosophy. Saturated fats are healthy -- just not in large amounts -- especially everyday intake of large amounts. Just because something is health promoting doesn't mean u need to keep uping your intake of the nutrient. Just as we need protein to build healthy bodies -- too much is dangerous, we need to figure out what values of fats and or protein are in the healthy range.

Fish oil can actually be viewed as a unhealthy nutrient for many of its effects on the body -- but in just the right amounts, it can be beneficial.

Remember, Stephan is under the assumption that high HDL with high LDL of the fuffy kind is not atherogenic. I believe that he is wrong here. I don't even care if your trigs are <50 in that regard.

[oehaut]

Alright. I'm new here and this forum is awesome. I've learn a bunch of very interesting things lately.

I've read about every subject I found interesting in the 19 pages of the nutrition threads, and many people here are pretty sure that saturated fat are bad.

I'm always looking for stronger arguments in favor of an idea (i'm trying as much as possible to be evidence-based) and so far i'm not convince about the harmfulness of SFAs.

Things can always change tho. I'm truely reconsidering my high-protein diet right now with everything i've read here.

That being said, I was thinking it would be a great thing to have a review of the controlled trial involving SFA modulation and CVD and total mortality outcome.

I'm starting my MSC in nutritional science this junary so i'm soon gonna be able to properly interpret a study with good research statistic skills. Right now, I gotta read paper and try to understand as much as I can, and obviously I rely upon others people thoughts a lot.

So, with this in mind, I don't feel like I can properly review the evidence myself. I've got all the papers on my PC so I can only corroborate what I read else where.

SO, that pretty long introduction leads us here : Saturated Fat and Health: a Brief Literature Review, Part II

I feel like Stephen from Whole Heart Source is one of the best blogger out there. I pretty much like this review because it goes straigth to the point.

Anthony Colpo in his Great Cholesterol Con's book did a very good job a reviewing the evidence too, but it's not available online.

What i'd like is that people read this post and comments on it. It's a pretty short read.

Here's the main point :

Out of 12 trials:

* Two trials found that replacing saturated animal fat with polyunsaturated vegetable fat decreased total mortality.
* Two trials found that replacing saturated animal fat with polyunsaturated vegetable fat increased total mortality.
* Eight trials found that reducing saturated fat had no effect on total mortality.

I know there's a lot of observationnal study out there, but since we have a bunch of controlled trial to rely upon, i'm not sure how much these observationnal study add to this. And anyone who have read Colpo's book will also know that the vast majority of prospective trial have not found any benefits of cutting down SFAs.

I'm really looking to have my current thinking challenge; i'm all open to change my mind if the evidence are telling me to do so.

So, is Stephan wrong here?

What evidence would make a good case against SFAs if most of the controlled trial didn't find any benefits from cutting it down?

Too many people here have an all or nothing philosophy. Saturated fats are healthy -- just not in large amounts -- especially everyday intake of large amounts. Just because something is health promoting doesn't mean u need to keep uping your intake of the nutrient. Just as we need protein to build healthy bodies -- too much is dangerous, we need to figure out what values of fats and or protein are in the healthy range.

Fish oil can actually be viewed as a unhealthy nutrient for many of its effects on the body -- but in just the right amounts, it can be beneficial.

Remember, Stephan is under the assumption that high HDL with high LDL of the fuffy kind is not atherogenic. I believe that he is wrong here. I don't even care if your trigs are <50 in that regard.

That's off topic but I can assure you that i'm far from having an all or nothing philosphy.

I'd say it's mainly health authorities who does that.

If you look at this Instutite of Medicine Report, you can read that they state :

Saturated fatty acids, trans fatty acids, and dietary cholesterol have no known beneficial role in preventing chronic disease and are not required at any level in the diet....Since there is no intake level of saturated fatty acids, trans fatty acids, or dietary cholesterol at which there is no adverse effect, no UL is set for them; instead, the recommendation is to keep their intake as low
as possible while consuming a nutritionally adequate diet,

It's common from Health Autorithies to lump SFAs and trans-fat togheter. Do you think that trans- are beneficial in small amount?

I'm not arguing people should consume as many SFAs as humanly possible - i'm questionning the believed held by many people that SFAs are bad if >10% of the total calories.

The message layman gets it that SFAs are terrible and should be kept as low as possible. Just like the institute of medicine state.

And the fact that Stephan think that fluffy HDL and LDL are not atherogenic doesnt add much to the result of the studies, i.e. no benefits for mortality from cutting sat fat.

Edited by oehaut, 01 December 2009 - 04:16 AM.

[HaloTeK]

I guess what I am trying to say is that "I" believe that at a certain point of saturated fat intake --- which might slightly vary between people -- you might reach a point where continuing to increase saturated fats in the diet "might" start contributing to heart disease.

Most of the studies you mention don't really look at people who are on 60%+ fat diets and eat 50+% of the those fats as saturated fats. Lots of paleo types and WAPs out their eat that kind of diet.

In short though, some saturated fats are good.

Our body does a great job of maintaining to usual ratios of saturated/monounsaturated fats in tissue -- polyunsaturates are the only fats that really can start to throw off the usual ratio we have in our tissue.

Why not just eat more monos because of their mostly neutral effect on the body.

Also, I don't think saturated fat up to 15% is going to be that bad. I hope data keeps streaming in on this.

[Singularity]

Dr. Eades, of Protein Power, argues that saturated fats are not dangerous if their proportion is kept in balance with the other fatty acids. He references studies in his argument.

Also, about 8 years ago there was a new weight-gaining diet/fad for those trying to bulk-up called the ABC (Anabolic Burst Cycling) Diet. They argued that primitive man's diet alternated between times of fasting and feasting, and that therefore our bodies can handle periodic gorging on meat and fat. After about 2 weeks of feasting on high fat/protein, your body begins to store the excess calories as fat. There is a lag time between when you first start the feasting phase before the body starts to store excess calories as fat. The idea is to then switch at this time to a low protein/fat diet for another two weeks. The goal of the diet was to pack on more muscle than fat and whatever little fat you did accumulate you can lose during the fasting phase where you aren't REALLY fasting, per sey, just eating leaner and more vegetables which also has a cleansing effect, imo. But, I can't recall if this diet was supported by experiments or not.

[kismet]

Singularity, forget the fad diet.

I'd like to see Stephan's review of all the data (and a list of those studies so that I can look them up when I'm bored). Just stating that studies found no effect, is not enough in most cases. You don't need a single study finding a significant effect for a significant difference to exist. I'd like to see a correctly done meta-analysis (correctly weighing studies according to size and quality or whatnot) or a systematic review.
Mixing studies replacing sat with CHO/MUFA/PUFA and other trials would be bad (possibly very bad) science, for instance.

[oehaut]

I guess what I am trying to say is that "I" believe that at a certain point of saturated fat intake --- which might slightly vary between people -- you might reach a point where continuing to increase saturated fats in the diet "might" start contributing to heart disease.

Most of the studies you mention don't really look at people who are on 60%+ fat diets and eat 50+% of the those fats as saturated fats. Lots of paleo types and WAPs out their eat that kind of diet.

In short though, some saturated fats are good.

Our body does a great job of maintaining to usual ratios of saturated/monounsaturated fats in tissue -- polyunsaturates are the only fats that really can start to throw off the usual ratio we have in our tissue.

Why not just eat more monos because of their mostly neutral effect on the body.

Also, I don't think saturated fat up to 15% is going to be that bad. I hope data keeps streaming in on this.

Ok actually I guess we pretty much agree then. I don't argue people should eat 50% total cal from SFAs but i'm not sure people should keep them as low as possible, especially if that mean getting more n-6. Thanks for you answer.

[oehaut]

Singularity, forget the fad diet.

I'd like to see Stephan's review of all the data (and a list of those studies so that I can look them up when I'm bored). Just stating that studies found no effect, is not enough in most cases. You don't need a single study finding a significant effect for a significant difference to exist. I'd like to see a correctly done meta-analysis (correctly weighing studies according to size and quality or whatnot) or a systematic review.
Mixing studies replacing sat with CHO/MUFA/PUFA and other trials would be bad (possibly very bad) science, for instance.

If you can get yourself a copy of Anthony Colpo The Great Cholesterol's book he pretty much review them one by one, you could get the data down.

You don't need a single study finding a significant effect for a significant difference to exist

I'm not sure i'm following you here but isn't the fact that most study don't find an effect from going, say, 15% of calorie from 8% of calories, is sufficient to think there might not be a significant difference?

Mixing studies replacing sat with CHO/MUFA/PUFA and other trials would be bad (possibly very bad) science, for instance.

That's why Stephan chosen only those 12 studies because they all reduce SFAs and add n-6. As far as I know none did it with MUFA.

I don't think they're any meta analysis of only SFAs and n-6 studies. The only meta-analysis i'm aware of had included n-3 in it too.


As for a systematic review, you might want to read this The questionable role of saturated and polyunsaturated fatty acids in cardiovascular disease

I don't know if that's the kind of things you're looking for.

[kismet]

You don't need a single study finding a significant effect for a significant difference to exist

I'm not sure i'm following you here but isn't the fact that most study don't find an effect from going, say, 15% of calorie from 8% of calories, is sufficient to think there might not be a significant difference?

Yes, it is, but it could also mean that there was no difference large enough to have been picked up by those studies. If, for example, 9 out of 10 studies show "not-significant harm" (i.e. p values of .10 or wide CIs) this is unlikely a work of chance and may be picked up by a meta-analysis.
A situation we see with very high doses of vitamins, e.g. vitamin E, individual studies find no significant effects on mortality but meta-analysis and systematic review shows that they consistently trend for the worse (ie. there probably is a very small, significant negative effect from high[ish] dose vitamin E).

But apparently the data is both very heterogenous and often of low quality so a systematic review may be a better approach than meta-analysis. And apparently he only included data on SaFa vs PUFA and data vs other nutrients may be unavailable. That's unfortunate.
Lots of lipid research is on my to do list, but I haven't come across a comprehensive list of RCTs (looking at *mortality*) yet or worthwhile comprehensive reviews.

Edited by kismet, 02 December 2009 - 11:22 PM.

[oehaut]

You don't need a single study finding a significant effect for a significant difference to exist

I'm not sure i'm following you here but isn't the fact that most study don't find an effect from going, say, 15% of calorie from 8% of calories, is sufficient to think there might not be a significant difference?

Yes, it is, but it could also mean that there was no difference large enough to have been picked up by those studies. If, for example, 9 out of 10 studies show "not-significant harm" (i.e. p values of .10 or wide CIs) this is unlikely a work of chance and may be picked up by a meta-analysis.
A situation we see with very high doses of vitamins, e.g. vitamin E, individual studies find no significant effects on mortality but meta-analysis and systematic review shows that they consistently trend for the worse (ie. there probably is a very small, significant negative effect from high[ish] dose vitamin E).

But apparently the data is both very heterogenous and often of low quality so a systematic review may be a better approach than meta-analysis. And apparently he only included data on SaFa vs PUFA and data vs other nutrients may be unavailable. That's unfortunate.
Lots of lipid research is on my to do list, but I haven't come across a comprehensive list of RCTs (looking at *mortality*) yet or worthwhile comprehensive reviews.

Yes, it is, but it could also mean that there was no difference large enough to have been picked up by those studies. If, for example, 9 out of 10 studies show "not-significant harm" (i.e. p values of .10 or wide CIs) this is unlikely a work of chance and may be picked up by a meta-analysis.

Ok gotcha.

I haven't come across a comprehensive list of RCTs (looking at *mortality*) yet or worthwhile comprehensive reviews.

Unfortunatly I don't think such a review exist. I've been reading about everything I could find in the past 2 years on the diet-heart hypothesis and if such a review was out there i'd come upon it already i'm pretty sure.

As usual in science we're left with probably more questions than answers. It's a common fact that other dietary factors are not taken into account. So, how can we make up our mind? Rely on observationnal study and conclude that SFAs tend to be link with higher mortality?

Unfortunatly it's impossible to have the perfect controlled trial ajusted for every possible factors.

How much do you think the bias that about every researcher in the nutrition world has agasint SFAs could contribute to the negative results of studies? I'm just wondering if this can make a difference somehow.

That's off topic, but last week in a class one of our teacher was telling us something happened to their research team lately : they found in a study that on a CR-diet, 50% of the participant REE increased.


They've submit their paper to many journal but NONE wanted to publish these result because their results were contrary to conventional wisdom. They had to review it again and again and again to finally have it accepted. And we're calling this science?

I can't help keep thinking how many time researchers that come up with result that could be in favor of SFAs can be reject like that. (or any others subject we'll never hear about simply because some people believe this could hurt what we think is the "truth").

I think your opinion is very valuable kizmet (from many threads i've read on the forum) and thanks for posting in. I'm lookin forward for some of your thoughts.

[JackChristopher]

I'm wondering if saturated fat is part of CVD, what's happens in weight loss where you consume your own saturated body fat?

Or what's the difference between consuming external SFAs and consuming it from fat stores? How do the metabolic pathways differ?

[oehaut]

I'm wondering if saturated fat is part of CVD, what's happens in weight loss where you consume your own saturated body fat?

Or what's the difference between consuming external SFAs and consuming it from fat stores? How do the metabolic pathways differ?

I don't think there are any difference.

I'm not sure if it's in this post that he was talkin about that but Stephan was saying somewhere on his blog that when you are very low-fat (high carb) the body start turning the excess carbs into palmitic acid, the exact same one that we get from food.

So I don't think the metabolic pathways differ at all from exogenous or endogenous SFAs.

To me, that SFAs would be harmful into a rather controlled diet just doesnt make sens Trying to avoid found on the basis that they contain SFAs is certainly not making sound choice. Like telling people to eat margarine instead of butter - because it contains SFAs.

Even the Masai, on a blood meat milk diet don't get much more than 30% of calorie from SFAs... so I don't even see how someone on a balanced diet could get more than 15%. And I just don't see how 15% could be harmful at all.

Meat is like 50% mono and 40% SFAs. I think the balance in nature between SFAs and mono is already really well done. If calorie are tracked and the diet is balanced well i'll repeat myself one more time but i've seen no evidence that SFAs per se can be bad.

Edited by oehaut, 06 December 2009 - 04:12 PM.

[JackChristopher]

I'm wondering if saturated fat is part of CVD, what's happens in weight loss where you consume your own saturated body fat?

Or what's the difference between consuming external SFAs and consuming it from fat stores? How do the metabolic pathways differ?

I'm not sure if it's in this post that he was talkin about that but Stephan was saying somewhere on his blog that when you are very low-fat (high carb) the body start turning the excess carbs into palmitic acid, the exact same one that we get from food.

So I don't think the metabolic pathways differ at all from exogenous or endogenous SFAs.

oehaut, I eat most fat calories as SFAs. I just asked this because I've never seen an explanation of how consuming bodyfat is differs. It's ironic that low-fat, low-calorie diets are actually high fat (majorly saturated) fat diets.

JLL made a blog post related to this. He found a study on rabbits fed high fat diets that tracked changes in body comp. It found that PUFA consumed changed bodyfat comp the most—it raises PUFAs stored. While MFAs and SFAs moderately changed it. Seems obvious that mammal bodyfat has a fat ratio/range that depends on diet.

So humans can saturated and unsaturate fat. And we even synthesize palmitic acid from the liver if low fat/high carb enough. But it's still unclear to me how consuming that fat differs. I can think of a couple potential differences in consuming exogenous fat; they seem more susceptible to dioxins and ALEs.

*Note: I know rabbits aren't made to eat fat or cholesterol but the study is quite relevant still.

[jughead]

And pufas are more oxidatively reactive. So saturated fats in store would be better than pufuas up to certain amount. What about those older studies that found highest saturated fat in the cell membrane led to LONGEST life?

[donjoe]

Indeed it seems the relationship between saturated fats and cardiovascular disease is more complicated than previously thought (SFAs are not always bad, not in every quantity, not for everyone, not in every dietary context).

Study: http://www.springer....s/journal/11745
Presentation: http://www.physorg.c...s205146842.html

[hypnotoad]

Meat is like 50% mono and 40% SFAs. I think the balance in nature between SFAs and mono is already really well done. If calorie are tracked and the diet is balanced well i'll repeat myself one more time but i've seen no evidence that SFAs per se can be bad.

I would tend to agree. Seems obvious that consuming protein wrapped in saturated fat (animals) is as old and natural as humanity itself.

The explosion of PUFA seed oils is NOT natural and only about 75 years old. 25,000 years ago man was eating the sat/mono fats of Aurochs, not the PUFAS in Hexane solvent extracted rapeseed and corn fats.

Add to that the fact that saturated fats resist oxidation and are the form of energy we store in our own bodies for fuel and its a clear win for saturated fat.

I think all animal fats we do eat need to be from sources where the animals ate a natural grass-fed diet (or in the case of birds, grains + insects). Eating the meat of inflamed unhealthy animals with screwed up 3-6 PUFA ratios is unlikely to be ideal for us over a lifetime.

I think Kurt Harris explains it quite well here: http://www.paleonu.c...o-you-fear.html

Edited by hypnotoad, 04 October 2010 - 10:39 PM.