Explain pro-biotics to me

January 3, 2023 2:23 PM

I had a stomach bug over the holidays and decided to follow some advice to get some GoodBelly shots (little drinks with good gut bacteria in them). Now looking these up online it seems like some people use these daily long-term. What's the point if that? Like can't I just give my gut a nice little seed colony and let them multiply in there from now on?

Also...this is just one kind.of bacteria...presumably there are lots of kinds and they might all like a boost. Can I get a bacteria variety pack?

Just to be clear I have no intention of drinking these things indefinitely. I'm just curious about the reasoning behind why one would (or if the reasoning is just marketing by the manufacturer).

posted by If only I had a penguin... to Health & Fitness (16 answers total)

Other things besides antibiotics can hurt your good bacteria or feed bad bacteria (causing them to out-compete the good bacteria). IIRC alcohol, sugar, stress, autoimmune conditions, etc. can all affect gut bacteria levels.

If you normally don't have issues then you probably do just need a one-time seed colony, but some people's bodies are in a constant state of internal warfare and thus they need to repopulate more frequently.

All the probiotic supplements that I'm familiar include at least a dozen different strains of bacteria. I didn't even know there were single-strain probiotics until I read this question and googled "GoodBelly" and saw that it only claims one.

That's just my layperson/consumer's understanding. Hopefully someone with a more scientific background can elaborate with greater detail and accuracy.
posted by Jacqueline at 2:43 PM on January 3, 2023

I suspect that it’s a big chunk of marketing combined with the incidentals of a person’s diet and lifestyle. We need a pretty wide variety of things in our diet to have a robust microbiome, and our bodies need to process those things well, and there’s a huge number of interactions we’ve only begun to understand about that.

Some people might have dietary restrictions, due to allergies and intolerances, location in a food desert, neurodivergence that means it’s much easier to stick to samefoods for calories and supplements for different nutrients, be physically different in how they break down and process foods (for example I am bad at oxalates which means I get kidney stones boo, no beets or spinach for me), have an illness that has impacted organ function (anything from cancer to an eating disorder to food poisoning), and so much more. Much like my mom takes fish oil pills I could see someone having a daily prebiotic shot simply for maintenance, basically.

This is not saying that I think they all actually do what they say they do, although because everyone is very different there’s probably a portion of folks for whom they are the best solution to a complex problem. Since our bodies are not perfect gardens there are tons of things that can go awry with your “little seed colony” and that could lead to someone wanting to “re-seed” daily. I think part of the idea of prebiotics though is that you kind of build up the basics that should lead to a variety of nutrients that are both directly ingested by you and as byproducts of the bacteria you’re trying to cultivate. At some point, new bacteria show up to consume those byproducts, and they make their own, etc. This should in theory lead to a robust microbiome that can handle whatever you throw at it, but again, everyone is different and it’s much more complicated than that.
posted by Mizu at 2:46 PM on January 3, 2023

Kimchi, sauerkraut, yogurt, kefir, and most greens do the same thing and offer taste and additional nutrition.
posted by theora55 at 2:47 PM on January 3, 2023

Probiotics have some intense PR in the last 10-15 years, like insane stuff, everything from it helps digestion to it cures serious mental health issues. So it’s marketing and also, people believe all kinds of trendy quackery (and there are of course legit reasons people mistrust traditional medicine/medical info.)

Yes, the number and variety of bacteria is a marketing point for probiotics.

People have always eaten yogurt and fermented foods like kimchi every day, so I don’t think there’s particular harm to taking these daily. I think people who take them daily feel it’s “maintenance” because they’re also eating and drinking things they feel throws off the balance.
posted by kapers at 2:53 PM on January 3, 2023

Good reasons and framing above (edit: on preview it's definitely not all quackery).

Ecologically, your gut is *wild*. We only know a tiny bit about it really. There's zillions of varieties of gut flora, and different ones can act similar and similar critters act different, both within and between individuals. Many of them interact with each other and you body in deep, complex networks of metabolic and communicative processes, and all that can be altered by other things the host is up to. (I'm an ecologist but not a gut ecologist.)

So yes, many people would see no benefit of a continued regimen. But many people may, and that's not just wishful thinking, although marketing and hype are also a huge in this area. While we know this stuff can be useful and important generally, it's really hard to talk about how specific things will work in a specific person with any certainty. The Mayo clinic says:

"When taking a probiotic, research the condition you wish to address and select the probiotic based on that condition. Also, keep in mind that while a probiotic may show promise in treating a condition, it's likely that the research is still in early stages.
While the supplement may have improved a condition for a few people in a very limited circumstance, it may not work as well in real-world settings."
posted by SaltySalticid at 2:59 PM on January 3, 2023

Probiotics are a lot like supplements:

There is some limited medical research suggesting health benefits in specific circumstances, but these have been exaggerated and over-generalized by an industry that wants to convince you they can treat any condition you have and that you should be taking them daily to remain healthy. The industry is barely regulated and can say basically whatever they want as long as they put the right asterisk next to it.

Probiotics have a lot of firm believers, due to the intense PR that kapers mentions, but it's all on very shaky scientific foundations. There isn't really a good answer to "what's the point" other than that it makes some people feel better and like they're doing something good for their health. Is it because the probiotics actually work, or is it because of the placebo effect or confirmation bias? IMO, for the average person the latter is more likely - otherwise we would have clearer research results supporting probiotics.

Here's an article:

Here's an article.

Here's another one.

Seriously, be skeptical of any and all marketing claims about probiotics. These products are marketed as though their benefits are settled science, but the marketing itself is what has created the impression that it is settled science in people's minds. The wellness industry in general should be approached with MASSIVE amounts of skepticism, and this is just one example.
posted by Kutsuwamushi at 3:14 PM on January 3, 2023

Changing your gut microbiome can take weeks or even months, depending on how it worked before the bug hit you.
The goodBelly shots can help it along, but they are not going to have any long term effect: you need to change the composition of your diet to include at least 25 grams of fiber every day and 30 different vegetable products a week*. If that was already your lifestyle, everything will be fine again within a week, and you can skip the shots. If this is completely new to you, you might have to wait for several months to get a result, and some of that time you may be farting a bit more than you want to. It's worth it, the farting stops. You will feel better, I promise. the GoodBelly shots help you get on, but they have very little effect compared to the overall lifestyle changes. Kefir, sauerkraut, kimchi and other fermented foods like live yogurt, aged cheese and vinegar will do more for you and be more tasty.

*the numbers here are what gut-doctors recommend, but in my experience, change happens with less fiber, if you keep up the variety of foods and the variety of probiotics, so not just one product but a good mix of fermented foods and fiber-rich foods
posted by mumimor at 3:36 PM on January 3, 2023

It's difficult to permanently change your microbiome with probiotic supplements. They don't generally reproduce in the gut. But they do good things during their short time there, including potentially encouraging the good bacteria you already have to reproduce.
posted by metasarah at 3:43 PM on January 3, 2023

I generally end up needing antibiotics a few times a year, and it's just easier to keep in the habit of taking the probiotics all the time instead of waiting for the antibiotics to do their thing. Plus, they might help some of the effects of my autoimmune conditions and won't hurt them, so why not.
posted by The Underpants Monster at 3:45 PM on January 3, 2023

You might find the book Gut, by Giulia Enders, interesting.
posted by penguin pie at 4:26 PM on January 3, 2023

The bacteria one usually finds in products marketed are probiotic are the ones that survive the digestion process of your stomach, and thus can be scientifically detected in your gut after consuming the product. They're not feeding you the best bacteria there is, only the ones that they know can make it past the stomach.

I have high hopes for probiotic therapies in the future; the weird but demonstrably beneficial fecal transplant (now in pill form) is a great start, and I'm also convinced pretty solidly of the gut-brain connection due to the plethora of research out there.

But as yet I've not been convinced that there's anything to this probiotic food/supplement business because none of them are doing an end-run around the stomach, and that's probably a good thing. Stick to your doctor's advice rather than buying a well-marketed bit of wishful thinking.
posted by Sunburnt at 6:34 PM on January 3, 2023

as yet I've not been convinced that there's anything to this probiotic food/supplement business because none of them are doing an end-run around the stomach

An unmodified human digestive tract has two ports to the outside world, and it's been my experience that yoghurt cultures migrate upstream rather faster than peristalsis sweeps them down again.

Doesn't take much. One 10ml syringe up the aft port settles everything down far more quickly and reliably than pints of the stuff fed in at the head end.
posted by flabdablet at 7:24 PM on January 3, 2023

Some probiotics come in pill form that help them pass through the stomach. Then you have to feed your biome, stuff it needs, foods high in fiber and slow digesting polysaccharides, cabbage, winter squash, steamed, (not baked down into simple sugars,) fruits with skin on, vegetables, beans, whole grains. Take them long enough to establish in your gut. If you have to take antibiotics, then take some more. If you drink heavily, high alcohol levels also effect your gut balance. It is not too difficult to keep some fiber in your diet.
posted by Oyéah at 7:35 PM on January 3, 2023

There is certainly a crying need for effective probiotics, not least to suppress deleterious elements of microbiomes:

Ethanol-Making Microbe Tied to Nonalcoholic Fatty Liver Disease

As its name suggests, nonalcoholic fatty liver disease describes a liver condition in which fat builds up in the livers of people who drink little or no alcohol. It can affect young, healthy people with no other comorbidities, leaving scientists and doctors stumped as to why some livers gradually fail.

A study published in Nature Medicine last week (October 10) provides clues as to a potential cause: the bacteria dwelling in our guts.

As they digest food, these microbes secrete byproducts, many of which are helpful. But some bacteria produce ethanol as they break down sugars, and a previous study in humansand mice linked ethanol-producing bacteria—namely Klebsiella pneumoniae—and fatty liver disease. In some patients, it appears, the commensal relationship between bacteria and host goes sour. The new study goes further, providing a potential mechanism for how ethanol-producing bacteria in the gut can evade diagnostic testing, stealthily dumping ethanol into the gut and wreaking havoc on the liver.

“This paper is a proof of concept. . . . It’s coming to complete the story that we didn’t have in the past,” says Juan Pablo Arab, a gastroenterologist at Western University in Ontario who was not involved in the study.
[…]

Lastly, the researchers sequenced the gut flora of the individuals from the first experiment and their healthy counterparts, searching for ethanol-producing bacteria. They found one likely candidate, Lactobacillaceae, a bacteria that produces lactic acid as well as ethanol, which was associated with NAFLD. Its presence correlated with high peripheral blood ethanol after a meal, indicating that it might be at least partly responsible for ethanol production. Meijnikman says, likely, Lactobacillacea isn’t the only bacterium associated with NAFLD—other bacteria may be the predominant ethanol producers in other individuals or populations. He explains that the previous study that associated Klebsiella with NAFLD was performed on a Chinese cohort, while the new study enrolled mostly white European participants, which may account for the disparate results.
[…]

But as other answers have suggested, no one seems to know how to reliably manipulate the microbiome to desired ends.
posted by jamjam at 7:38 PM on January 3, 2023

The thing about probiotics is that they are aerobic bacteria. The thing about gut microbes is that they are anaerobic bacteria. So probiotics is more about changing your diet, the way eating vegetables is a dietary change, as opposed to actually seeding new cultures of critters inside you.

The bacteria that causes fermentation is in the air and on surfaces all around us. Leave the milk out on the counter overnight and it will most likely grow a nice culture of the kind of bacteria you find in probiotics. You are eating tiny trace amounts of them all the time and even breathing them in. They are very easy to replace. Those bacteria are going to get inside you sooner or later, even if you don't eat a probiotic supplement. Taking on a lot of them or eating them regularly is a similar dietary change like eating cabbage. It might make your digestion work better, or if you are unlucky there is a tiny chance it might react badly with you and make you a little uncomfortable and bloated, but it won't do you any harm. Acidophilus is found in any food with a high starch content - You are already eating probiotic bacterial strains because they are in any food you eat that has not been recently pasteurized.

Replenishing anaerobic symbiotes inside you is much harder than getting the aerobic bacteria. In fact we still don't know how the anaerobic bacteria gets inside us, and how it survives to do so. It does seem to pass from the primary caretaker to the newborn over a period of days because the infant ends up with the same strains as the primary caretaker but it doesn't seem to be transmitted through the milk. Otherwise it may be that we get it from exposure to soil. Chances are your best bet then, would be to take up gardening if you want to replenish the bacteria that lives in your lower digestive tract.
posted by Jane the Brown at 1:01 AM on January 5, 2023

The thing about probiotics is that they are aerobic bacteria.

Yeah, nah.

Lactobacillus acidophilus (New Latin 'acid-loving milk-bacillus') is a rod-shaped, Gram-positive, homofermentative, anaerobic microbe first isolated from infant feces in the year 1900.[1] The species is most commonly found in humans, specifically the gastrointestinal tract, oral cavity, and vagina, as well as various fermented foods such as fermented milk or yogurt.

posted by flabdablet at 1:11 AM on January 5, 2023