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Fermented Foods: Definitions and Characteristics, Impact on Gut Microbiota etc.

ncbi.nlm.nih.gov

21–23 of 23 posts

Re: Fermented Foods: Definitions and Characteristics, Impact on Gut Microbiota etc.

#21
post #8

The paper shows the fundamental flaw and short-sightedness that characterizes life sciences in general. Every single fermented food is treated as if it were a high potency drug. For example, in one study, for each day of a week people in the groups would eat either 110g of sourdough bread or 110g of white bread. Really, is that your experiment? You are trying to detect differences between eating 110g of two breads, o…

That's really not outside the realm of possibility for something to change the microbiome. That's a quarter pound of bread, two servings and about 280 kcal on the loaf I have in front of me. That's a reasonable amount for someone to consume as part of a normal diet. We know small changes in diet can have a large effect on the microbiome. For example, adding seaweed to a mouse diet can select for microbes with the abi…

Your estimate is off by almost an order of magnitude. 100g is not 10% of a person's weight. Maybe you meant 10% of calories.

Also, look at the comparison. It is seaweed! Wouldn't you expect that eating 10% of your weight in seaweed changes a microbiome? It is a massively different food than what we (or mice) typically eat - thus the microbiome has to adapt. I am not saying the discovery is not important - it is the right question, set up correctly.

Compare that to a human eating two slices of different breads for a week. The differences between bread are too subtle. The amount ingested is too little, the time is too short. Your microbiome is already set up for digesting bread. That's all I am saying -

I will stick to my story that there is very little chance that this would ever be sufficient to detect any change.

Re: Fermented Foods: Definitions and Characteristics, Impact on Gut Microbiota etc.

#22
post #3

>common fermented foods (kefir, kombucha, sauerkraut, tempeh, natto, miso, kimchi, sourdough bread) I can get everything on that list easily at a non-specialty store except for natto. I haven't seen it, but I admit my ability to read labels at the Japanese food store is rudimentary. Is it more widely available on the west coast?

You can make natto, it is easy and starter cultures are realy cheap.

Re: Fermented Foods: Definitions and Characteristics, Impact on Gut Microbiota etc.

#23

I'm a little surprised that a paper basically concluding that there are no good papers about fermented foods is able to published and presented as research by these authors. Or maybe that field is just so lacking in knowledge that this passes for research. You would think that they'd take the next step and do some trials to advance the field.

I don't understand the conclusion you draw from reading the paper (the full text is accessible for free from the link to the right). that there are "no" good papers studying fermented foods.

What I read is that the _majority_ of the studies are not good quality. There are very few high-quality studies e.g. double-blind randomised controlled trials and crossover studies, etc and most studies have a very small number of subjects. However, it's hard to fault a double-blind RCT for low quality because it has few subjects. Low statistical power, OK, but if the methodology is sound then the paper has merit.

Given that these studies go back a number of years and there is still no conclusive evidence for any health benefits from the consumption of fermented foods it is useful to have a summary of the current state of research.

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