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It’s time for L. acidophilus and the rest of the health-affirming probiotics gang to come out from behind the umbrella term so we can differentiate the benefits of each.
One of several casualties of the single-minded assault on germs sponsored jointly by cleaning product commercials and modern healthcare providers is the collective misunderstanding of probiotics, which we blame in part on this collective refusal to list them individually.
From the time you were old enough to reach curiously over the lip of the kitchen wastebasket, you were likely lectured on a regular basis about germs.
Bacteria are germs, and germs cause diseases, says the modern medical establishment.
Why on earth, then, would anyone intentionally seek out bacteria-rich foods (aka, probiotics) for health benefits?
The truth is that many bacteria can be helpful, and in fact, there are roughly 100 trillion bacteria living in the average person’s intestinal tract.
This bacterial environment is referred to as the gut microbiome or the “intestinal microbiome,” and it houses many benevolent bacteria that help our bodies digest food, fight off sickness, and more.
Here’s how it all works.
In addition to probiotic supplements, fermented foods like yogurt, kombucha, sauerkraut, and others naturally contain high amounts of bacteria found in the human gut microbiome.
When we consume these foods or supplements, we add to our existing population of benevolent bacteria, shifting the microbiome towards a healthier and more capable state.
Prebiotics, on the other hand, feed the bacteria instead of supplementing or replacing them.
For example, many bacteria within this microbiome prefer to dine on starch and fiber, a useful attribute that helps us get more from these foods.
Finally, synbiotics are foods or supplements that contain both prebiotics and probiotics.
In many cases, synbiotic foods (commonly, yogurt) are fortified with one or more bacterial cultures to meet this definition.
Following is a basic overview of the most common bacterial cultures within the gut microbiome and their benefits.
The most common probiotics contain one or a combination of six species of bacteria divided evenly between two groups, Lactobacillus (L) and Bifidobacterium (B).
These bacteria include:
According to this fact sheet from the National Center for Complementary and Integrative Health, foods containing these bacteria can enhance the body’s immune response, prevent antibiotic-associated diarrhea, treat infant colic, and over 20 other evidence-supported applications.
Let’s break it down by each of the six bacteria, starting with L. acidophilus.
This study by Massachusetts General Hospital for Children proved that L. acidophilus can modify the immune system in a way that reduces inflammation in premature infants suffering from a condition called necrotizing enterocolitis (NEC).
Like many inflammatory conditions, NEC is associated with an “overreaction” from the immune system, only this time, the overreaction is associated with immature immune systems.
The researchers in this study used L. acidophilus on human intestinal xenografts (cells from humans implanted in other animals) to test the probiotic’s effects on NEC, determining that the probiotic exerted a protective effect by promoting maturation of immune system cells.
Diverging from the usual focus on inflammation and digestion, this trial from the University of Toronto in Ontario, Canada showed that L. casei can actually address behavioral and mood-related symptoms of chronic fatigue syndrome (CFS) in humans.
Experimental group participants showed fewer symptoms of depression and anxiety than the placebo group after a 60-day regimen of daily L. casei supplementation.
Serotonin is also produced in the gut, adding to the implication brought forward by this finding: the human gut and brain are closer together than they look.
As mentioned, several probiotics have been investigated as potential anti-inflammatory agents, including L. plantarum, which was proven by this study from the National Dairy Research Institute in Haryana, India to be particularly effective in this regard.
According to the study, L. plantarum administered to mice increased their uptake of anti-inflammatory compounds (like interleukin-4) while decreasing uptake of pro-inflammatory compounds (like tumor necrosis factor alpha and cyclooxygenase 2).
Like L. casei, the probiotic B. longum has also been shown to help with psychological and/or behavioral issues.
This study from Universiti Tunku Abdul Rahman in Perak, Malaysia explains how B. longum, along with another probiotic called L. helveticus, “significantly decreased anxiety-like behaviour in rats and showed a reduced psychological distress in human subjects.”
This observation may seem redundant, following that of L. casei, but it’s important to note that these benefits were upheld in a much broader context this time (not limited to chronic-fatigue-related symptoms).
And it’s back to the anti-inflammatory category once more for B. bifidum, a probiotic found by this Nestle Research Center (Switzerland) study to partially protect mice from inflammation related to chemically induced colitis.
According to the authors, B. bifidum significantly reduced “levels of pro-inflammatory cytokines” in the tissues of tested mice.
Kefir, yogurt, berries, and apples are among just a few foods rich in B. bifidum prebiotics and probiotics, an attractive option for colitis sufferers (remember, mind your fiber during flare-ups!).
Finally, B. lactis was shown by this study from the University of North Parana-unopar in Brazil to have beneficial effects on the lipid profile of patients with metabolic syndrome.
To clarify, “lipid profile” refers to the levels of different types of cholesterol in a person’s bloodstream (triglycerides, high-density lipoproteins, etc.), and “metabolic syndrome” is a group of conditions characterized by high blood glucose, obesity, and other risk factors for cardiovascular disease and diabetes.
Specifically, the study proved that B. lactis decreased total cholesterol, body mass index (BMI), and inflammatory compounds in subjects who consumed 80mL of fermented milk daily (over 45 days).
In the vast majority of cases, probiotics, prebiotics, and synbiotics need time to work.
The intestinal microbiome is not an on-off switch; it’s a huge “community” of bacteria that can be shifted into a more favorable state with consistent consumption of probiotic- and prebiotic-rich foods.
As always, exercise will help probiotics do their jobs better, especially those that boost metabolism.
For anyone who approaches a probiotic-rich diet as a lifestyle shift (and not a 2-week crash diet), incorporating exercise and healthy nutrition in other areas, probiotics can make a major difference in overall wellness.
Energy drinks and sugary snacks may be louder, sweeter, and faster-acting than natural sources of sugar, but rarely are those benefits conferred without some form of reckoning down the road.
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