5 ms·

Some studies show bacteria from fermented foods colonizing the colon and others do not, although regular consumption does tend to marginally increase microbiome

Some studies show bacteria from fermented foods colonizing the colon and others do not, although regular consumption does tend to marginally increase microbiome diversity (a generic and in many ways crude measure of GI health). In theory, an optimally functioning GI tract would be killing a majority of the live bacteria long before they reach the colon via a combo of enzyme activity, stomach acid, bile, pancreatic enzymes, and immune activity on the way down. What has been more consistently shown is fermented foods causing decreases in GI inflammation and other positive impacts. Some researchers now believe that many if not most of the benefits come from all of the microbial action prior to consumption. Fermenters such as Lactobacteria do a lot of work for us ahead of time, such as breaking down so-called 'anti-nutrients' and converting low-bioavailability nutrients into high bioavailability nutrients, producing anti-inflammatory metabolites, outcompeting pathogenic bacteria and fungi, and so forth. Bacterial fermentation has even been shown to break down pesticides [0], aflatoxins [1], and other potential contaminants present in the raw food. I wouldn't be shocked if microplastics and/or PFAS gets added to that list, at least under certain conditions, in the coming years. [0] https://www.tandfonline.com/doi/abs/10.1080/10408398.2012.677872 https://www.tandfonline.com/doi/abs/10.1080/10408398.2012.67... [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3737493/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3737493/

elcritch 3y ago
> Some researchers now believe that many if not most of the benefits come from all of the microbial action prior to consumption. That seems counter to the whole idea behind modern research on the importance of the gut microbiome and a throwback to the thinking of the previous century. Certainly some of the work of bacteria is done before but that’s well known as many foods are fermented but the cultures are killed or pasteurized afterwards. Classic American yoghurt was like this, but there’s clear benefits to yoghurt with live cultures. Even if many bacteria don’t colonize the gut their presence in the food or taken separately appears important. In my opinion the evidence is overwhelming that actual probiotic bacteria themselves are important, not just their by products in the food. Our immune system detects healthy bacteria both living and dead and lowers inflammation in response, etc. There’s a lot of research on the topic and good summary research (1, 2). The presence of the bacteria also change the gene regulation in the intestines. Fecal transplants can directly treat diseases, or trigger diseases with maladaptive bacteria (3). 1: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8512487/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8512487/ 2: https://www.sciencedirect.com/science/article/pii/S2772502222001457 https://www.sciencedirect.com/science/article/pii/S277250222... 3: https://www.frontiersin.org/articles/10.3389/fimmu.2022.991788/full https://www.frontiersin.org/articles/10.3389/fimmu.2022.9917...
- slothtrop 3y ago
  Yeah but fecal transplant bacteria isn't comprised of the sort of transient bacteria generally found in probiotic sources. It leads to a kind of hard-reset for gut flora. There are few sources that offer bacteria that will persist in the gut, I think I read kefir is one of them, but to what extent I'm not certain.
  - elcritch 3y ago
    Even transient probiotics provide benefits too. Even when killed by stomach acid they trigger certain beneficial pathways. Many, perhaps most, traditional diets from around the world featured some live-culture fermented dish as a staple. Likely our bodies evolved to expect large daily exposure to certain healthy bacteria, and societies that ate live cultures with those bacteria would have better health.
mjan22640 3y ago
Fungi will start feeding on plastic in the environment relatively soon. Digesting plastic in an animal digestive tract is a tougher nut to crack, similar in principle to digesting celulose.
- syndicatedjelly 3y ago
  Citation?
djtango 3y ago
yeah I always found it a little counter intuitive how eating bacteria would be good for my gut insofar as most the GI tract is meant to be major gauntlet for bacteria. But I get dodgy IBS-like issues eating spicy food but consuming fermented foods in proximity really helps settle the stomach. ie Kimchi affects me less than other spicy dishes while eating natto after having a lot of spice can really help. Ditto for yoghurt but I'm lactose intolerent and so many lactose-free yoghurts are full of crap
- jalk 3y ago
  What crap is in lactose-free yoghurt? Afaik they add lactase which lactose tolerant ppl still “produce” after weaning. So the lactose is simply “pre-digested” into glucose and galactose.
  - djtango 3y ago
    most dairy free yoghurts (and lactose free yoghurts) are full of stabilisers and sugar
- ahoka 3y ago
  Could be any other reason. BTW, you can make your own yoghurt, it’s very easy.

elcritch 3y ago

> Some researchers now believe that many if not most of the benefits come from all of the microbial action prior to consumption. That seems counter to the whole idea behind modern research on the importance of the gut microbiome and a throwback to the thinking of the previous century. Certainly some of the work of bacteria is done before but that’s well known as many foods are fermented but the cultures are killed or pasteurized afterwards. Classic American yoghurt was like this, but there’s clear benefits to yoghurt with live cultures. Even if many bacteria don’t colonize the gut their presence in the food or taken separately appears important. In my opinion the evidence is overwhelming that actual probiotic bacteria themselves are important, not just their by products in the food. Our immune system detects healthy bacteria both living and dead and lowers inflammation in response, etc. There’s a lot of research on the topic and good summary research (1, 2). The presence of the bacteria also change the gene regulation in the intestines. Fecal transplants can directly treat diseases, or trigger diseases with maladaptive bacteria (3). 1: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8512487/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8512487/ 2: https://www.sciencedirect.com/science/article/pii/S2772502222001457 https://www.sciencedirect.com/science/article/pii/S277250222... 3: https://www.frontiersin.org/articles/10.3389/fimmu.2022.991788/full https://www.frontiersin.org/articles/10.3389/fimmu.2022.9917...

slothtrop 3y ago
Yeah but fecal transplant bacteria isn't comprised of the sort of transient bacteria generally found in probiotic sources. It leads to a kind of hard-reset for gut flora. There are few sources that offer bacteria that will persist in the gut, I think I read kefir is one of them, but to what extent I'm not certain.
- elcritch 3y ago
  Even transient probiotics provide benefits too. Even when killed by stomach acid they trigger certain beneficial pathways. Many, perhaps most, traditional diets from around the world featured some live-culture fermented dish as a staple. Likely our bodies evolved to expect large daily exposure to certain healthy bacteria, and societies that ate live cultures with those bacteria would have better health.

mjan22640 3y ago

Fungi will start feeding on plastic in the environment relatively soon. Digesting plastic in an animal digestive tract is a tougher nut to crack, similar in principle to digesting celulose.

syndicatedjelly 3y ago
Citation?

djtango 3y ago

yeah I always found it a little counter intuitive how eating bacteria would be good for my gut insofar as most the GI tract is meant to be major gauntlet for bacteria. But I get dodgy IBS-like issues eating spicy food but consuming fermented foods in proximity really helps settle the stomach. ie Kimchi affects me less than other spicy dishes while eating natto after having a lot of spice can really help. Ditto for yoghurt but I'm lactose intolerent and so many lactose-free yoghurts are full of crap

jalk 3y ago
What crap is in lactose-free yoghurt? Afaik they add lactase which lactose tolerant ppl still “produce” after weaning. So the lactose is simply “pre-digested” into glucose and galactose.
- djtango 3y ago
  most dairy free yoghurts (and lactose free yoghurts) are full of stabilisers and sugar
ahoka 3y ago
Could be any other reason. BTW, you can make your own yoghurt, it’s very easy.