New study on dietary fat and satiety

[NTB]

A study of dietary fat and satiety, just published in Nutrition Journal, was summarized as follows in today's Food Navigator:
http://www.foodnavigator-usa.com/Science-Nutrition/Fat-all-the-same-for-stopping-hunger-pangs-Study/?c=yk34w4mL6gpMNh2cKqmYOw%3D%3D&utm_source=newsletter_daily&utm_medium=email&utm_campaign=Newsletter%2BDaily

It does not matter what form fat is consumed in – saturated, mono- or poly-unsaturated – they all perform poorly when it comes to producing a feeling of fullness, says a new study.  Previous studies have suggested that polyunsaturated fats may be more effective at suppressing appetite that mono-unsaturated fats, but a new study published in Nutrition & Metabolism finds no difference. “In this study we were unable to show differential changes in postprandial feelings of hunger or fullness, or changes in energy intake at a lunch meal when alterations were made to the fatty acid saturation of a high-fat breakfast,” wrote the researchers from the University of Auckland in New Zealand.

I'm very skeptical of these conclusions, particularly the claim that all fats "perform poorly when it comes to producing a feeling of fullness".   Of course, important details are not revealed here, such as what the actual foods were.  Were they palatable?  Were the fats combined with significant amounts of carbohydrates?  Inquiring minds want to know.

I don't even need to read the study to know that it is wrong, because it goes 180 degrees against what my own experience tells me.  High fat meals are very filling for me, and I'll bet for most people.  And doses of pure fat -- whether they be flavorless SLD doses, or even flavored "platinum calorie" doses, suppress appetite.  Now perhaps there are situations in which fat is not always so filling, or for some people.  But it is true often enough that "fat is filling", that we can be certain that this study is flawed in concluding that all fats perform poorly in suppressing appetite.

So I went from the trade journal report to the actual study and learned the following:
http://www.nutritionj.com/content/pdf/1475-2891-9-24.pdf

The breakfasts were high in saturated (SFA, 65% of total fat), polyunsaturated (PUFA, 76%) or monounsaturated (MUFA, 76%) fatty acids, and comprised 2 savoury muffins.

So the "high fat breakfast" is 2 savory muffins!!!!  No mention of the carbs and the savory flavor here at all in the original public puff piece!  None of this was mentioned in the puff piece.

My bigger beef is that this is the type of misleading study that we are seeing more and more. The study design and details are obscured, but the conclusions are trotted out for the public.  And for some reason, people tend to believe this stuff, and doubt their own experience.  Somebody had an anti-fat agenda here, and that led them to design a shoddy study with poor controls, just to make a news splash. 

Long live self-experimentation!

[anacara]

Wow! Unbelievable isn't it?!!?! You'd have thought that a high fat breakfast designed to test whether fat contributed to satiety, could take the form of, say, bacon and eggs, wouldn't you? I guess that was too simple! Perhaps they thought they had better include carbs so that the breakfast would still be "healthy".

[goblyn]

I just don't understand what the motivation for flubbing a study just to prove something that you obviously know to be untrue.  Well okay, I understand the motivation ($$$) but I just don't understand why you'd want to continually perpetuate lies! 

I'd love to know what these "savoury muffins" even are in the first place.  How something composed of more than, say, two or three ingredients could EVER bee used in dietary testing.  There are so many variables going on there. 

In fact, don't say that fat conclusively does anything unless you're simply isolating fat (in the form, of say, oil) and having the subjects intake just that.  Why this study isn't being just laughed right out of the door is beyond me, but then I've found many times that purportedly "scientific minded people" have little common sense and logic.  If its written in a paper, then it MUST be true! After all someone wrote it in a paper!  A PAPER!  Wow!  Aren't you impressed?

Well neither am I, and yet, everything is just automatically accepted as fact, regardless of how ridiculous the experiment was run.

[karky]

just as bad as the study I saw on the news the other day where they claimed high fat made asthma symptoms worse because their test subjects had more symptoms after eating a 1000 calories of hamburger and french fries compared to 200 calories of low fat yogurt

ridiculous

How do they know it wasn't the bun, or the potatoes, or the meat, or even the quantity of food causing the symptoms.

My asthma symptoms improved considerably after I started tossing back oil shots.

[An Alchemist]

Has anybody actually read this study, or just condemning it for going against our preferred ideas?

I don't pretend to know the answers, but it's difficult to see how we can be discerning if we refuse to even look at it. Who knows, maybe there's something there, and we can learn something. It just seems to me if we're not willing to look, then we're basing our actions on faith. I dunno... 

[NTB]

Has anybody actually read this study, or just condemning it for going against our preferred ideas?

I don't pretend to know the answers, but it's difficult to see how we can be discerning if we refuse to even look at it. Who knows, maybe there's something there, and we can learn something. It just seems to me if we're not willing to look, then we're basing our actions on faith. I dunno... 

Alchemist, I agree with you that we should actively seek information that discomfirms our favored theories, because that protects us from falsehood.  Which is why I was interested in reading this study in the first place and why I linked to the entire original publication (see the second link in my original post, which goes right to the journal article).  And it was only when I read the full article, not the "digested" version presented to the public, that I found the little "detail" about the fat being present in the form of muffins. Here for convenience is a link to the full article again: http://www.nutritionj.com/content/pdf/1475-2891-9-24.pdf

I would be very interested in any research showing that pure fat, or fat not combined with carbohydrates, produced an in increase in appetite. If the study were well designed, I would pay attention and learn something from it.  I might even change my beliefs if the evidence were compelling, and I could confirm it on my own. But this particular study was very poorly designed, because it did not test fat alone.  I went back  to check the article and learned that the muffins were made from the following ingredients: flour, skimmed milk powder, eggs, tomato, ham, test lipid.  Figure 3 in the study indicates that more than half of the energy of the content was carbohydrate (CHO); fat represented only about 25-30% of the total energy.  So there was more carbohydrate than fat in the muffins! Would you describe these muffins as "high fat" or "high carb" -- or both?

My point here is not that I disagree with the findings, but rather with the interpretation of the findings. I disagree because the methodology of the study was flawed, and that the public version of the article was very misleading by failing to disclose key "details" that tend to undermine the credibility of the conclusions.

Imagine if the title of the public piece had been: "High carbohydrate muffins fail to suppress appetite".  That title could have equally well been justified by the data, perhaps more than the original title, and I think it would have created an entirely different message to the public.

On a micro scale, this article embodies exactly the kind of scientific sloppiness that Gary Taubes exposed in Good Calories, Bad Calories, where he unravels the faulty experimentation and analysis that led to Ancel Keys' lipid hypothesis regarding the role of fat and carbohydrate in cariovascular health and obesity.  This is not a minor error; it is a monstrosity that was perpetuated on all of us over 50 years, and that led at least in part to the current obesity epidemic, with associated health issues.

[nougat]

todd
so when a knowledgabel person like yourself reads these kinds of studies is there nothing you can do about it?
to me they sound like blatant lies.  and they will be accepted as the truth....more bs to confuse poor fools like me.
why are such things allowed to stand as gospel?  what's to be done??

[NTB]

todd
so when a knowledgabel person like yourself reads these kinds of studies is there nothing you can do about it?
to me they sound like blatant lies.  and they will be accepted as the truth....more bs to confuse poor fools like me.
why are such things allowed to stand as gospel?  what's to be done??

I used to shrug these things off, but now I feel a sense of responsibility about this because of the impact that poor science has on public education and even public policy.  I sent a note to the journal editor earlier today, pointing out the problems with the article and urging him to issue a corrective comment.  I let him know that if his journal is not more careful in the review process, it would lose credibility and readership.  I know two other people who sent in similar letters.

[nougat]

well done!!
i'm so glad there are people like you - knowledge and conscience!!  a rare combination it seems!

[An Alchemist]

It's prolly all relative. How does the fat compare to 'regular' muffins. Are they 'high-fat' even if they aren't 'all-fat'?
Most people don't eat all fat, or all carb anyhow, so this is prob more relavent to us than if they had people eating hunks of lard.

I guess your word choice threw me off, cause you said you didn't need to read it to know what to think, so it sounded like you were making an opinion without reading it. sorry.    But back to my point: even if you don't fully agree, there's probably something to learn from it if we comb thru it. I think a lot of valuable ideas get lost in the shuffle when they're next to things we don't agree with.

[goblyn]

just as bad as the study I saw on the news the other day where they claimed high fat made asthma symptoms worse because their test subjects had more symptoms after eating a 1000 calories of hamburger and french fries compared to 200 calories of low fat yogurt

ridiculous

How do they know it wasn't the bun, or the potatoes, or the meat, or even the quantity of food causing the symptoms.

My asthma symptoms improved considerably after I started tossing back oil shots.

Or, lets say the burger was fast food, rather than a homemade burger and fries.  I'm willing to bet that it was loaded up with preservatives, trans fats, additives, flavor modifiers, and all other lovely bits of variables!  Who could possibly say for sure that any one thing caused this to happen!

Its just funny, because one of the things I've always retained from my science courses in high school and college was that when you're performing an experiment, you have to be aware of all the potential variables and try to reduce them as much as possible.  How can a hamburger and fries (or a muffin) be anything BUT variables???  If this is what they're teaching us in the basic science courses, then why the heck don't professional scientists follow it?

[Pinkmug]

I read that article on burgers and asthma on FB and left the same exact comment as Karky... asthma being caused by allergies, why not assume there must be an allergic additive, and assume it's the fat up front??

Post hoc, ergo propter hoc, but no one even knows what exact hoc it was!