Tabagas_Ru

Here is something that some of you may find interesting on how protein affects certain hormones that help reduce appetite.

Here is the link to the full text PDF manuscript.

The manuscript is interesting and it has some info on how the hormones work. Also included are some interesting charts.

The following is the abstract.



Acyl and Total Ghrelin Are Suppressed Strongly by Ingested Proteins, Weakly by Lipids, and Biphasically by Carbohydrates
Karen E. Foster-Schubert*, Joost Overduin, Catherine E. Prudom, Jianhua Liu, Holly S. Callahan, Bruce D. Gaylinn, Michael O. Thorner, and David E. Cummings

University of Washington School of Medicine (K.E.FS., J.O., H.S.C., D.E.C.) Seattle, Washington 98195; Veterans Affairs Puget Sound Health Care System (K.E.FS., J.O., D.E.C) Seattle, Washington 98108; University of Virginia Schools of Medicine (J.L., B.D.G., M.O.T.) and Arts and Sciences (Chemistry) (C.E.P.) Charlottesville, Virginia 22903

* To whom correspondence should be addressed. E-mail: kfoster@u.washington.edu.

Context Ghrelin is an orexigenic hormone that can increase body weight. Its circulating levels rise before meals and are suppressed following food ingestion. Understanding the effects of specific types of ingested macronutrients on ghrelin regulation could facilitate design of weight-reducing diets.

Objective We sought to understand how ingestion of carbohydrates, proteins, or lipids affect acyl (bioactive) and total ghrelin levels among human subjects, hypothesizing that lipids might suppress ghrelin levels less effectively than do either carbohydrates or proteins.

Design Randomized, within-subjects cross-over study

Setting University Clinical Research Center

Participants 16 healthy human subjects

Interventions Administration of isocaloric, isovolemic beverages composed primarily of carbohydrates, proteins, or lipids

Main Outcome Measures Magnitude of postprandial suppression of total and acyl ghrelin levels (measured with a novel acyl-selective, two-site ELISA)

Results All beverages suppressed plasma acyl and total ghrelin levels. A significant effect of macronutrient class on decremental area-under-the-curve for both acyl and total ghrelin was observed; the rank order for magnitude of suppression was protein > carbohydrate > lipid. Total ghrelin nadir levels were significantly lower following both carbohydrate and protein, compared to lipid beverages. In the first 3 postprandial hours, the rank order for acyl and total ghrelin suppression was carbohydrate > protein > lipid. In the subsequent 3 h, there was a marked rebound above preprandial values of acyl and total ghrelin after carbohydrate ingestion alone.

Conclusions These findings suggest possible mechanisms contributing to the effects of high-protein/low-carbohydrate diets to promote weight loss, and high-fat diets to promote weight gain.


Key words: ghrelin • macronutrient • diet • carbohydrate • protein • lipid • obesity • weight loss

ModoVincere

Thanks for the information and the link.

Enthalpic

Look around, I read an article about a signalling peptide released by the gut in response to a high protein meal. The review I read was in scientific american about 2 years ago IIRC.

Basically it's this peptide that is altering the leptin, ghrelin, etc energy balance feedback mechanism.

Tabagas_Ru

Thank you for that info, I appreciate it.

I understand that you read the article a few years ago, but do you remember any more details that can hone me in on the of which you speak.

Thank you.

Enthalpic

I think it was P YY in that article.


Many gut peptides have been shown to influence energy intake. The most well studied in this regard are cholecystokinin (CCK), pancreatic polypeptide, peptide YY, glucagon-like peptide-1 (GLP-1), oxyntomodulin and ghrelin. With the exception of ghrelin, these hormones act to increase satiety and decrease food intake.
https://www.ncbi.nlm.nih.gov/pubmed/1...ractPlusDrugs1


Critical role for peptide YY in protein-mediated satiation and body-weight regulation.
https://www.ncbi.nlm.nih.gov/pubmed/1...ubmed_RVDocSum
Our findings suggest that modulating the release of endogenous satiety factors, such as PYY, through alteration of specific diet constituents could provide a rational therapy for obesity.

Tabagas_Ru

Thank you for the information.

Tabagas_Ru

I took a closer look at the study and it looks and sounds if there is a chance of a type 1 error. It was still very interesting to see the results.

The ghrelin levels fell faster and further with CHO ingestion than protein or lipid ingestion, while lipids fell the least and the slowest, followed by protein, which was in the middle of the 2.

The interesting part is that the CHO levels showed a large rebound effect whereas protein and lipids did not. It also took longer to reach the lowest ghrelin levels in protein. As well, levels with protein came up to baseline slower than either lipids or protein. This seems to have resulted in levels that were suppressed for a longer period of time overall.

The CHO was glucose so they say that there would be a different effect if they used fructose as the CHO. They claim that fructose is not metabolised into glucose; therefore ghrelin levels do not drop very much. In essence, the CHO’s that affect ghrelin levels need to be converted to glucose to show the effect that they achieved in the study.

So what?
What do you think the implications of these results hold if the study if their findings are the truth?

I know the study is not the real world, and that it was highly controlled compared to real life. Still, I think it would be interesting to see how this could be applied to different types of diets.

Now my interpretation is that simple carbs should normally be avoided if you want to be satiated for a longer period. I don’t believe that it says that all CHO’s should be avoided but that with the combination of the 3 nutrients you can manipulate satiety to suit your needs.

So what do you think of this as a simple plan:
Keep simple carbs to a minimum if you wish to eat less, avoid processed sugar as much as possible.
Try to keep simple carbs to a minimum during a meal, and make sure to eat protein and fat with you meal.
Try experimenting with the nutrient levels and the times that they are eaten. For example: will eating simple carbs before a meal to lower levels make you eat less during the meal, or if it followed with fat and protein with this lengthen the time that levels stay below baseline?
To kill hunger without a large rebound that makes you hungrier, have a protein shake of your liking with minimal carbs.

I know that there is more than one way to skin the cat, and I may have only ended up sticking the knife into my arm. I am also aware that this is an extremely simplistic view and life is more complicated than this study, but I think it would make for good conversation to explore others’ view of the results.

ModoVincere

Barry Sears has been saying this exact same thing since the mid 90's.

Carbonfiberboy 

Let me say this about that. In general, one tends to eat better, more wholesome and balanced foods during a meal. So I don't think it's a great idea to eat a carb snack before a meal. Remember your mother's caution about "spoiling your dinner" with candy. She was not a fool. Most of us and our parents have known of this effect for a long time. OTOH, I have found it to be beneficial to have a high protein snack before a low protein meal. Perhaps this study explains why that works so well.

"In the subsequent 3 h, there was a marked rebound above preprandial values of acyl and total ghrelin after carbohydrate ingestion alone."

The rebound effect from carbo only consumption is very noticeable. I commented further on this in your "High protein and weight loss" thread.

Tabagas_Ru

I guess you are right I can't really argue with mom.

Thanks for the protein tip I think I will have to try that.

babydee

I find that high-protein meals make me more satisfied, for longer, than high carb or high fat. Simple sugars are not my vice, salt is (alcohol has also been), so I don't eat much of them anyway.

I've been lifting weights again and picking up the bike riding, and I am really liking having a good amount of protein with each meal, 5 meals a day, maybe 160-200 grams a day.

(I'm 6'2", 194lbs.)