
Fermented Foods: Definitions and Characteristics, Impact on Gut Microbiota etc. - YeGoblynQueenne
https://www.ncbi.nlm.nih.gov/pubmed/31387262
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Matticus_Rex
Anecdotally, I've been sick for a total of one day since I got deeply into
fermentation as a hobby about a year ago (largely thanks to the Noma Guide to
Fermentation). On an average day, I eat at least one live lacto-fermented item
and drink kombucha, and at least every few days I have something that includes
an uncooked live vinegar. I normally get sick at least a couple of times a
year. My mood has also been consistently pretty good all year.

It's definitely anecdotal, but it's a significant enough shift for me to think
it might have something to do with the fermentation. Bonus: it's delicious,
and after much experimentation my kombuchas are now better than commercial
kombucha.

~~~
harshreality
2 days to 1 day for N=1 patients over 1 time period is not significant.

"Feeling better" could be real or it could just be cognitive bias. Did you use
an app to record your mood multiple times a day? Were you taking less time
(better contration) on cognitive tasks? Measurably fewer aches and pains?
Better performance during workouts? Or did you have blood panels done and some
values were better? Or none of those things?

That you say it's delicious is a confounding factor, as well, because eating
food that tastes better improves your mood which can make you feel better
without any nutritional or microbiome-related health effects.

To be clear, I'm not criticizing fermentation at all, just whether this
anecdote provides any meaningful evidence for anything.

Also, even if there is some statistical significance since "a couple"
apparently means far more than 2, since fermented foods displaced other
things, what did they displace? Could those have been making you unhealthy
rather than fermented foods making you healthier? You'd have to trial non-
fermented dairy and tea and veggies as a control, and that control doesn't
work very well with dairy because non-fermented dairy is high in simple sugar
which can be bad all by itself.

~~~
Matticus_Rex
"A couple of times a year" is not two days -- it's usually 6-10.

It was, as I said, quite anecdotal, and I'm very aware of the possibility of
various cognitive biases. I also have enough stats knowledge to understand
that I have not achieved a significant result. Even with that integrated, it
has seemed noticeable enough for me to think it may be related.

I have no shortage of delicious food available, nutritional/live or not. I
just pointed out that it's a reason to enjoy it anyway. I'm not doing it for a
health experiment.

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supernova87a
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.

~~~
bane
My guess would be that, due to the very regional nature of many fermented
foods, research into those foods is probably locked in the languages and
localities of those foods. Heck, there's an entire Kimchi research institute
in South Korea.

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glofish
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, once a day for one week?

Why would anybody in their right mind expect any change in the microbial
composition of the gut? Or anything really...

Thus the reality is that not only there is almost no research in the field -
that little that is performed is absurdly badly done.

~~~
boldlybold
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
ability to digest particular polysaccharides within seaweed
([https://www.nature.com/articles/s41586-018-0092-4](https://www.nature.com/articles/s41586-018-0092-4)).
A company spun out of the Sonnenburg lab at Stanford is using this tech for
microbiome therapeutics in humans (Novome). Those mice were given 10% seaweed
by weight, so that serving of sourdough is right in the same range.

My point is, the researchers designing these experiments know what they're
doing, and they're well thought out. You can't criticize something if you
don't know the details of the field.

~~~
glofish
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.

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Slothrop479
To anyone interested, these three lectures from the Royal Institution cover
the topic of the microbiome:

\- Why Dirt and Microbes Could Be Good for Us:
[https://www.youtube.com/watch?v=xlEFI5A3QFM](https://www.youtube.com/watch?v=xlEFI5A3QFM)

\- The Microbes Within Us (I Contain Multitudes):
[https://www.youtube.com/watch?v=UOymDhGxS9Q](https://www.youtube.com/watch?v=UOymDhGxS9Q)

\- What Role Does our Microbiome Play in a Healthy Diet?:
[https://www.youtube.com/watch?v=-LUuqxQSaFQ](https://www.youtube.com/watch?v=-LUuqxQSaFQ)

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Isamu
>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?

~~~
chabes
On the west coast:

You can get it at Mitsuwa in the Bay Area. 99 Ranch might carry it as well.

Not sure about elsewhere.

~~~
Isamu
Hey, looks like Mitsuwa is in NJ and Chicago; good to know!

