Big Breakfast Alters Appetite, Gut Health | Hacker News Reader

Big Breakfast Alters Appetite, Gut Health

cambridge.org

51 pointswjb346 comments

The abstract begins, "Growing evidence supports early eating to control appetite and energy balance". What does that mean? My unskilled reading of it is that there is recent evidence that eating breakfast helps with weight loss. But I'm confused because there was a 2019 meta-analysis that found that eating breakfast does NOT help with weight loss. https://www.bmj.com/content/364/bmj.l42

The problem there might be what people are eating for breakfast.

Right.

How many of these studies used buttered eggs and potato as the sole breakfast?

It means the replication crisis is alive and well.

You might want to read the rest of the studies - or at least try to no misrepresent before commenting. There are elementary differences in the studies.

Study 1: "What to Eat", Specific Demographics, Primary Clinical Trial, Mechanistic/Physiological Outcome, Conclusion: High-Protein breakfast is superior for suppressing appetite and maintaining satiety, while a High-Fiber breakfast promotes better weight loss and a healthier gut microbiome,

Study 2: Whether to Eat, Broad Demographics, Systematic Review (meta analysis), Broad Clinical Outcomes, Conclusion: eating breakfast increases total daily energy intake compared to skipping it, and that skipping breakfast resulted in slightly greater weight loss.

I wasn't comparing the two studies. I was just asking what the first sentence of the abstract of study 1 meant when it appears to be a false statement given study 2's result. Usually this is because I don't understand something and someone around here explains what I'm missing.

Uncool. OP asks for help understanding, and you attack them for not understanding.

19 participants.

>> therefore 19 participants completed the study (2 females and 17 males) and their data are presented throughout

Who in their own mind decided that this is a "study" worth publishing?

Someone with quotas

You're reading the study wrong.

You read

  We saw this effect, so it's real.

In actuality it is

  We saw this effect in a small study, so it's worth doing a larger study.

It's worth publishing because it's evidence and motivation to do further studying. And if you're asking "Why not start large?" the answer is obvious: money.

Especially in dietary studies. You either spend a lot on high quality, controlled studies where you can nail down parameters (takes a LOT of labour), or you spend on facilitating much larger studies where you make up for precision and control with volume.

There are trade offs in either case and some types of research where one is more suitable than the other. But the best case is a combination of the two, and it's exceedingly rare.

Maybe there are other options but this seems to be the polar nature of these studies from what I've seen.

> We saw this effect in a small study, so it's worth doing a larger study.

That never happens.

That doesn't change the meaning.

Reading it wrong tends to make that happen too. Since people read it as fact they end up arguing "why fund a more expensive study to show the same thing?"

A lot of this stems from not understanding how science actually works. How there's never proof, only confidence bounds

The paper includes a section on power analysis which justifies the sample size (although the justification is for a sample of 20, they recruited 25 eligible participants and lost 6 in screening).

Some points though:

- A within-participants study has inherently more power than a between-subjects study. Trying two different diets with the same person removes a lot of variables that you'd need to control for in between-subjects studies (and yes, they randomized the order of intervention and found no difference based on order)

- It looks like this was conducted in a way that supported compliance with the protocol, and using analysis techniques that would be unwieldy for a much larger sample size.

Even with N=19, the reported significance is very compelling.

Average age was 57, which may be rather high. Also: why not test out combining both diets?

That was the point I stopped reading.

The number needed for a study to get significant results depends on the strength of the effect it is measuring.

For example if I have a bag full of thousands of coins, pull out 19 at random and flip them sequentially, and they all come out heads I'm going to conclude I have a bag that is overwhelmingly coins that are heavily biased toward coming up heads.

Are you going to say my sample size was too small to support that conclusion?

To see if their sample size was too small you need to at least read the part where they do the math.

True, or you can have a prior about how many people you need to get a significant result in a certain area.

I have one for "diet changes have large impact" and the number is different enough feom 19 that I'm happy to stop reading at that point.

go on, explain why you think there is a problem with the sample size. But no words, only clear statistical calculus. I'll wait.

Intermittent fasting + eat breakfast like a king, lunch like a prince and dinner like a pauper worked miracles for me.

study says we should do a real study

Yes, because you need evidence from small studies to justify running larger ones. You're not going to run an n=1000 experiment from a mere guess.

I think the frustration is: it's not "news"

Countries known for big breakfasts: USA, Turkey.

Countries known for light or skipped breakfasts: France, Japan, China.

I think I'll wait for a more thorough study.

Buddha recommended to his followers a diet which consisted of a breakfast and a second meal at noon if needed. That is, for their health, primary meal early in the day and fasting the remainder. It's interesting that this advice seems fairly supported by science.

OMAD people usually do the opposite: black coffee and then a big dinner.

This study wasn't big breakfast vs light/no breakfast.

It was high fiber big breakfast vs high protein big breakfast.

(And no, this comment was not written by an LLM).

The study doesn't try to say that big breakfasts are good or bad in general (it leans on previous works for that).

It's trying to determine the impact of the composition of said breakfast.

The full title of the paper is: "Big breakfast diet composition impacts on appetite control and gut health: a randomized weight loss trial in adults with overweight or obesity"

(I don't think "with overweight" is a great turn of phrase)

Interesting but they had no control.

The whole study design seems odd.

Why not add a third high-fiber + high-protein group for example?

They would have needed 20 participants, which is too many.

Soon we will have more participants in the HN comments for the study, than were studied in the study.

im thinking you would need a group to skip breakfast too ...

I feel like the regular weight loss group was? Since it isn't necessarily rocket science for having mostly men stay in an easily determinable caloric deficit to lose weight. (Women have usually would be harder due to more conditions and hormone interactions that make finding a TDEE not as simple.)

They didn't eat that much.

They used a crossover design, so each subject served as their own control. Not a bad choice for trials like this as you gain a lot of statistical power with fewer participants than a parallel-arm, non-crossover design.

I don't think they used crossover design. There is no evidence in the abstract that they used crossover design.

If they used crossover design they should have all participants go through a second trial period where they consume the same diet but with light breakfast and more caloric lunch and dinner. Then they could actually have more insight on the main thesis of their study, i.e. whether bug breakfast alters appetite.

They did. Check out Figure 2 in the paper.

They did a crossover study on the two diets. Ie the high protein diet and the high fiber diet. They did absolutely no crossover or no control on the headline thesis of their paper. The headline being that big breakfast alters appetite or is somehow good for weight-loss.

This study shows or proves absolutely nothing about advantages or disadvantages of big breakfast or that a big breakfast makes any difference whatsoever.

It only shows that if you are going to have a big breakfast as part of calorie limited diet if you choose a diet with high protein you will lose weight slightly faster but will have slightly worse gut health than if you chose a diet with high fructose.

TLDR: A weight loss diet centered around a big breakfast yields weight loss results. That breakfast loaded with protein made you feel fuller and suppressed your appetite (which helps you follow a diet), where a fiber loaded diet produced more beneficial gut bacteria.

The study has a pretty small sample size, but it seems well designed and matches what you'd expect.

"big meal alters appetite" is a hell of a conclusion. Definitely going to need to study that one.

Appetite is intertwining endocrine functions that contain way more moving datapoints than just stomach empty vs stomach full.

It sounds like this study might have been funded by.... Big Breakfast.

I'll see myself out.

Dammit I came here to make this joke

The IHOP/Waffle House duopoly ramping up the science to validate their ideals.

Big, if true.

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