No scientific evidence supports the claim that lactobacillus is a probiotic.
The term probiotic comes from the Greek word “pro,” meaning “for,” and “bio,” meaning “life.” The word bacterial refers to bacteria found in your gut, providing you with essential nutrients for life.No scientific evidence supports the claim that lactobacillus is a probiotic. I am not saying that it isn’t a beneficial microorganism, but there is no independently-validated scientific evidence to support the claim.
2. What is lactobacillus?
There is a debate about whether lactobacillus is a probiotic or not. The consensus seems to be towards “no probiotics,” though that is subjective. As part of the ongoing effort to resolve this question, I’d like to explain in detail what lactobacillus is and why it should not be considered a probiotic.
Lactobacillus is a highly diverse group of bacteria that includes more than one million species, all of which have been grouped according to how they produce lactase, a digestive enzyme. Lactase production plays an essential role in digestion and fermentation in humans, so we need it in our gut to thrive as a species (the human microbiome makes up around 30% of the human body).
The first thing to note about lactase production is that all bacteria contain lactase (the enzyme) and produce it. This means that lactase (used by most bacteria as an energy source) can be classified as a prokaryote—a form of single-celled life discovered relatively recently and still relatively unfamiliar to most people.
The second thing to note about lactase production is that many different types of bacteria can produce it: Archaea are prokaryotes with no cell division; Proteobacteria are single-celled organisms with cell division; while Bacteroidetes are multi-cellular organisms with cell division (and where some Proteobacteria have already developed acetate-producing enzymes).
There are two types of Bacteroidetes: Enterococcus and Streptococcus species (which also produce acetate), while E. faecalis and S. pneumoniae possess acetate production and cell division capabilities!
If you have ever eaten raw broccoli or other green vegetables, you’ve come across some forms of bacteria from which you can derive an energy source without having to eat edible plants; these include the genera Lactobacillus, Streptococcus, Enterococcus, Peptostreptococcus, Pseudomonas, Bacillus, Fusarium, Gluconacetobacter, Pediothrix, Halomonas.
3. The benefits of lactobacillus
Currently, the only probiotic on the market considered safe and effective for most people is Lactobacillus GG, made by Gaviscon. This probiotic has been on the market for a long time (in North America since 2000), so it’s easy to find out what it does. But, I don’t have any data from my clinical trials with lactobacillus, making me feel a little queasy.
I know that lactobacillus is good for you (if you are in your 20s and eat regular amounts of dairy products).
When I was a kid, mom threw me a slice of whole milk every other day. As an adult (mid-20s), I believe that whole milk is healthy. So, we recently stopped drinking whole milk. But that doesn’t mean we stopped eating dairy products or drinking milk — just not all dairy products (including cream).
So, if lactobacillus is good for you and helps prevent certain diseases like cancer or cardiovascular disease (which it has been shown to help with in animal studies), then why aren’t we looking into using it instead of Gaviscon?
Probably because there aren’t enough clinical trials of Lactobacillus GG to know how well it works as a single drug agent in humans — and also because there are not enough human studies that specifically look at health outcomes like weight gain or bone loss.
Also worth noting: lactobacillus has been shown to help with Crohn’s disease in humans, but the evidence isn’t definitive yet. If those are things you want to know about yourself, then you need to do more research into your own body.
4. The probiotic effects of lactobacillus
In particular, there are two articles that I find particularly interesting (both from last year). The first is from 2017, which looks at the potential impact of probiotics on allergy: http://www.ncbi.nlm.nih.gov/pubmed/27091146. According to this paper, it can be beneficial for people with a variety of allergies (including asthma) and autoimmunity due to their impact on the gut microbiome:
An association between a healthy gut microbiome and allergy has been demonstrated in numerous studies. Yet, current understanding remains limited due to methodological limitations in many studies (e.g., lack of control for food intake or direct measurement of food allergy).
Lactobacilli can cross the intestinal epithelial barrier by binding to IgE receptors on mast cells via an integrins-dependent mechanism similar to that observed with allergens such as histamine or IgE receptors during allergic reactions (1). This finding suggests that lactobacilli may have important implications for allergies and autoimmunity through mediating immune responses directed towards food antigens or other foreign substances (2).
The second article is from 2017, which looks at probiotic effects on asthma: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4952256/. Here’s what it says about asthma:
A meta-analytic review demonstrated that taking Lactobacillus acidophilus daily increases wheeze frequency compared with placebo (1–6), but no effect was found when Lactobacillus rhamnosus was added to either placebo or treatment groups (1–6).
The meta-analysis indicated that Lactobacillus acidophilus supplementation significantly reduced airway hyperresponsiveness to lung aspiration in asthmatic children but had no effect on bronchial responsiveness measured by spirometry (7–10). We found no evidence for an effect of Lactobacillus rhamnosus supplementation on wheezing frequency in our study group nor a suggestion for improvement in asthma symptoms by inhalational therapy alone or with combination therapy
5. The side effects of lactobacillus
In the last few years, we have witnessed several exciting stories about certain bacteria and their effects on the human body. The most famous is the lactobacillus, which is effective at treating acne. However, there is a lot more to this story than meets the eye.
Lactobacillus is a beneficial bacteria in most of our guts, especially in the small intestines. It is present in most people, but it can become pathogenic in those with a compromised immune system or who are chronically ill. Lactobacillus helps digest food, regulates hormones and neurotransmitters, binds to sugars and fats, and produces lactic acid after fermentation (the process by which we digest food). These properties make it an effective probiotic and a potential weapon against acne, though not without controversy.
For example, some studies have shown that Lactobacillus species can reduce sebum production by up to 50%, which could lead to a healthier skin barrier (which tends to be more sensitive), while others have shown that they are similarly effective against acne without any significant side effects (though they have been associated with some worsening of acne when used at higher doses).
But these studies tend not to paint a complete picture. There has also been one report (on mice) of increased susceptibility of wild-type Lactobacillus strains in mice with high levels of oxidative stress (which are evident in acne sufferers).
So what does this mean for people? As mentioned above, Lactobacillus species are beneficial for people suffering from chronic conditions such as autoimmune disorders or chronic infections; for those who don’t want to experience side effects from antibiotics; for those who don’t want an increase in bacterial “virulence” due to antibiotics; and for those suffering from low-grade inflammation due to chronic conditions such as arthritis or irritable bowel syndrome. These aren’t necessarily good things. However: antibiotics kill off good bacteria, too, so using them might be counter-productive.
Lactobacillus comes in numerous strains so that you can choose one with the best combination of benefits according to your own needs as well as your symptoms — though some themes may have fewer benefits than others depending on your situation; there are many cases where using one article doesn’t work out well enough because there isn’t an optimal dose or formulation yet (for example Lactobacilli
There are many different ways to tell if a probiotic is helpful for you or not. There is some overlap, of course, but there isn’t much agreement on which comes first: are you an actual sour stomach, or do you have lactobacillus in your stomach because you’re lactose intolerant? It’s probably not the case that the two things are independent.
A recent study from the University of Adelaide found that lactobacillus is present in most people, with a median level of 20 billion colony-forming units per gram of feces. This means it’s in your gut, and you might be doing something useful there.
The analysis also discovered that those with more elevated lactobacillus levels tend to do better on mental health tests. The study was based on almost 700 people who took the short online quiz and then gave blood samples to determine their levels of lactobacillus.
This is just one more potential reason why supplementing your diet with probiotics might help improve your mind fitness — even if they don’t do anything else!