Digesting the complex metabolic effects of diet on the host and microbiome

(Bob M) #1

I’m only partway through this, but this is one of those studies where I think “Wow, the human body is so complex…”.

https://www.cell.com/cell/fulltext/S0092-8674(24)00706-2

Just look at part of what they say about “calories”:

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It’s interesting that intake of fiber could cause more excretion of energy.

I’ve also always thought that it was interesting that two 2,000 calorie keto diets, one high(er) protein, and one higher fat, the actual calories on the higher protein will be “lower” due to diet-induced thermogenesis.

This is another interesting figure. So much for meat causing obesity:

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Anyway, there’s a ton of stuff in here.

#2

Thanks for sharing this. I believe the gut biome will become The hot topic in the next few years. Still not in the mainstream. As much as we think we know about this and that, be prepared for lots of changes.

#3

It’s definitely complex but it’s human body for you. And there are individual factors too…

Wow, that idea is new to me. WHY? :smiley: The opposite would make much more sense to me. I know some weird beliefs but I can’t imagine the explanation for that. Anyway, the modest meat intake don’t even have much calories let alone extra ones while the copious amount of carbs do and they are less satiating and easier to put into everything, we don’t even need more complex things to consider…

By the way, I don’t even have the vaguest idea about the recommended amount of vegs and fruits, I never ever saw grams or sugar grams or anything and “portion” says absolutely nothing to me. One day I may get too curious and try to figure it out. But I am not sure they ever say it properly. Do they? But my aim is usually zero either way, I fail but I fail less if I go for zero (or the least amount humanly possible at the moment or something).

(Bob M) #4

@ffskier In my mind, the biome does … something. In the paper, they discuss where the biome affects whether animals (mainly) over- or under-eat. I know some people who believe the biome is THE cause of overeating. I’m not sure about that, but don’t know.

The problem is that it’s very difficult to test this. If you eat differently, your biome changes, and they don’t have good studies about this.

Just listened to a podcast, where they are going to put people on a keto diet for depression, and they are going to test what happens to the microbiome and whether that has any effect on depression. This is the youtube version (I listened to the podcast):

https://www.youtube.com/watch?v=Oye7lz0HYnI

There are multiple reasons they are looking at the biome, but one is because there are so few studies that have done this for the keto diet. And they are going to try to quantify what happens to the biome and attempt to relate it to mental benefits. We’ll have to see what happens.

@Shinita There’s the idea that somehow meat is harmful, such as leading to diabetes. My daughter is going to a dietician, and the dietician has suggested something like 3.5 ounces of meat per meal. Uh, what?

There is no evidence to support the suggested “servings” of fruits or vegetables. It’s not like they ran an randomized trial where some people ate 3 “servings” a day and some ate 5 “servings” a day (with maybe a trial where people ate whatever), and there was a difference. The number of servings is a guess. And it’s based on epidemiology – people who said they ate so many fruits/veggies per day were healthier than those who said they did not.

I tend to eat just meat, but right now, I’m eating a few more vegetables, as I like tomatoes from the garden. But in general, I eat much less than the number of “recommended” servings, though like you, I don’t keep track.

(KM) #5

Looking at this chart, what I find both glaringly obvious and elegantly simple is that the consumption of meat, eggs, dairy, nuts, legumes, fruits and vegetables has barely moved in 50 years. Logically speaking, none of these foods are the villain in today’s health crisis. Why on earth is so much research focused on those elements of diet!

That’s a rhetorical question; oil, grain and sugar are the unholy trinity protected from scrutiny by Big Food and Big Ag, not to mention the junk-addicted masses, pun intended. Still, it’s more reinforcement to avoid those elements.

And thanks, yes, a ton of well organized data to digest here!

#6

You bring up some good points, and I will follow the study. About five years ago, I started to do a dive into the gut biome and the brain/gut barrier. I was concerned with my lack of hunger, regardless of my level of activity. This would suggest that my ghrelin had become disregulated. Ghrelin’s job, as far as I can tell, is to signal to the brain that we are hungry. It may play other secondary roles as well. The other main hunger hormone is leptin. This is created in the white adipose tissue and small intestines. Basically, it signals to the brain that you are full and to stop eating. It has been shown that many overweight and obese people are leptin resistant. I have read studies where re-colonizing the gut can better regulate these hormones. I will post once back at my base.

There are some biohackers that are doing some amazing things in this space and, most importantly, are doing it simple with real food.

I

#7

Of course it’s unbased but I have no problem with the number of servings but with the servings. I don’t have any idea what is “one serving is”, 40g fruit/veg, 100, 400? :smiley: All are perfectly valid portions if you ask me (just like 10g and 1000g too) and I don’t know about some specific fruit portions, it varies wildly.

Of course I have heard about weird things about meat (so weird I never ever entertained the idea to wonder about its validity) but obesity is especially odd and unusual to me. As I never ever could get obese on a diet high in meat, it’s a nice, satiating item (and perfectly normal for an omnivore anyway).

Interesting… So it may be not just the changed woe but the changed biome due to changed woe too… I did notice difference in my satiation after carnivore even when I went off for a longer time but IDK how quickly the gut biome can change. I know close to nothing about this topic. (And there is the changed mental part too so good luck to figure out myself what is the reason…)

(Edith) #8

I wonder how they would separate out the microbiome having an effect on the depression from the ketones having an effect on the depression. Like you said, the body is sooooo complex!

(Bob M) #9

Maybe I should open a separate thread about the biome? Here’s a study that was a randomized controlled study of twins where they gave one of the twins some prebiotics. The twins that got the prebiotics did better on a test of cognition, but not better on standing up from a chair.

https://www.nature.com/articles/s41467-024-46116-y

The couldn’t quantify the benefit, but they have an interesting discussion:

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The hard part about a lot of these is that they have a hard time determining which bacteria is causal. This study found a positive association between “actinobacteria” and their outcome, but they say other studies haven’t.

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