Most people aren’t aware of the importance of gut health. The gut is literally the center of your body, and its influence expands far beyond that of digestion.
There are trillions of bacteria in your gut that play an important role in everything from digestive health and cognitive function to immune health and, yes, even weight management.
But not all gut bacteria are created equal. The combination of bacteria, fungi, parasites, and other microbes that reside in your gut can elicit both favorable and unfavorable effects, depending on their ratios.
When the good guys outnumber the bad guys, expect good things. But when poor lifestyle choices allow the bad guys to proliferate, watch out for what’s coming.
Interestingly, though, research has discovered specific strains of bacteria that may link the microbiome and bodyweight. Studies show that people who are overweight or obese have a drastically different gut composition than people of normal weight.
So, we’re diving into everything you need to know about probiotics and the link between how your gut composition can affect your weight.
What Are Probiotics?
Probiotics are one of the most widely consumed gut supplements on the market. Touted as the cure-all for restoring gut health and mitigating digestive symptoms like gas and bloating, you’ll find them in everything from energy bars to drinks.
But what are probiotics? They are a complex of live microorganisms that, when given in large doses (we’re talking in the billions), can offer a slew of positive health benefits to the host 1.
But the benefits aren’t equal across the board. Certain strains of bacteria confer different benefits. For example, the Lactobacillus strains naturally inhabit the small intestine and are most effective for supporting gut barrier integrity, bowel function, and immunity.
The Bifidobacterium strains populate the large intestine (colon) and support digestion, mood, and stress response. Because bacteria populate the entirety of the gastrointestinal tract, the gut bacteria residing in each location will offer different health benefits.
Probiotics come in several strains, including Saccharomyces, Streptococcus, Enterococcus, Escherichia, and Bacillus. Most probiotic supplements on the market are a mix of several strains, but if you’re looking for a specific effect, going after a single strain can be more beneficial.
Regardless of what you choose, probiotic supplements are shown to be effective for repopulating and rebalancing the gut, thereby boosting overall health.
Here are some of the benefits probiotics can offer:
- Balance bacteria in the digestive tract
- Prevent and treat diarrhea
- Regulate mood and benefit mental health
- Improve heart health by regulating cholesterol levels
- Improve conditions linked to autoimmunity
- Decrease inflammation
- Reduce symptoms of digestive disorders
- Boost immune health
While probiotics are generally well-tolerated by most people, they don’t come without their risks. Regulations on probiotic supplements are pretty lax, so if you’re ordering online, you want to make sure you’re buying a reputable product.
On top of that, any probiotic that is “shelf-stable” and not refrigerated likely isn’t going to be super effective. Different strains of bacteria have different sensitivity levels, and not all strains can be freeze-dried to become shelf-stable.
If they’re not processed and stored properly, chances are they’re dead before you’re even consuming them.
Probiotics And Prebiotics: What’s The Difference?
Two words you’ll often hear about when gut health comes up are probiotics and prebiotics. Although similar in name, these two compounds are not the same.
Probiotics are the live bacteria that populate the gastrointestinal tract, while prebiotics are the food these organisms use for fuel. Humans don’t possess the enzymes needed to digest prebiotic fiber, but bacteria do.
Just as we need food to survive, so do the bacteria in your gut, and if you’re not feeding them what they need, they can’t perform optimally (or at all).
These prebiotics are selectively used by host microorganisms (gut bacteria) and can manipulate the composition of host-microbiota 2. Rather than contributing additional strains that have dodgy efficacy in your gut, prebiotics function is to nourish the already present strains.
Generally speaking, prebiotics are complex carbohydrates that are metabolized by gut microbes to produce short-chain fatty acids (SCFAs) like acetate, propionate, and butyrate 3. These SCFAs all offer their own health benefits, too.
Simply put, probiotics are the live micro-organisms themselves, while prebiotics are the fuel that helps probiotic bacteria thrive.
How Probiotics Affect Body Weight
Although there’s a host of different functions that gut bacteria benefit from, one of the major interests is with probiotics and weight. The mechanisms aren’t well understood, but research shows that probiotic bacteria may influence appetite regulation and energy usage via the production of short-chain fatty acids like acetate, propionate, and butyrate 4, 5.
Other research suggests that it may inhibit the absorption of dietary fat, thereby increasing the amount of fat excreted in feces and reducing how much is absorbed.
In simple terms, they can help to reduce the number of calories absorbed from foods. This has been proven true for certain strains, especially in the Lactobacillus family 6.
Probiotics may also offer some great benefits to fight against the obesity pandemic 7-10:
- Release appetite-regulating hormones like glucagon-like peptide-1 (GLP-1) and peptide YY (PYY), which help to enhance energy expenditure and fat burn
- Elevate levels of the fat-regulating protein angiopoietin-like 4 (ANGPTL4), which may help to decrease fat storage
What’s more, the powerful effects of probiotic bacteria on the gut and the integrity of the gut lining may help to maintain health of the GI tract and reduce systemic inflammation that can lead to obesity and other diseases 11.
Here are some of the ways probiotics may boost weight loss 12:
- Influence intestinal gene expression involved in regulating energy balance
- Regulate intestinal barrier function
- Regulate satiety hormone release
- Regulate digestion and absorption of nutrients
- Generate short-chain fatty acids (SCFAs)
On top of that, research consistently shows that people who are overweight or obese exhibit drastically different gut microbiome profiles compared to healthy people 13.
One possible mechanism is that microbiomes may influence weight gain via the gut-brain axis—the bidirectional signaling pathway that connects your gut to the brain 14.
This axis is one of the primary reasons why when we’re stressed, we feel more hungry. It’s also possible that alterations in the compassion of gut microbes can induce inflammation, which has been linked to weight gain and obesity.
Can Probiotics Help Weight Loss?
With all of that said, there is a role for probiotics in weight loss. A 2017 systemic review and meta-analysis of studies looking at the role of probiotics and weight loss in overweight or obese people found that supplementation can support weight loss and reduce body fat percentage 15.
Specifically, certain strains of Lactobacillus seem to be particularly effective for supporting weight loss and reducing belly fat.
One study even found that people who ate yogurt with Lactobacillus fermentum or Lactobacillus amylovorus lost, on average, 3–4% body fat over six weeks 16. Several other studies also show that Lactobacillus gasseri offers powerful anti-obesity properties.
Several strains of probiotics within the Lactobacillus and Bifidobacterium family are shown to reduce weight and belly fat, with Lactobacillus gasseri exhibiting the most beneficial effects.
Final Thoughts
When it comes to gut health (and overall health), probiotics are necessary, but supplementation wise they’re nowhere near as effective as prebiotics.
You may think you’re getting billions of live bacteria, but thanks to manufacturing and shipping processes, you run the risk of having a dead-on-arrival probiotic. As a result, you’re increasing the risk of nasty side effects.
So how do you mitigate the risk and actually get what you’re looking for? A good prebiotic is definitely the way to go.
Performance Lab® Prebiotic is a 2-in-1 prebiotic + soluble fiber supplement designed to support healthy metabolic and microbiome performance.
Instead of adding new colonies, Prebiotic nourishes existing probiotic colonies with Orafti® Synergy1 (Inulin-FOS from chicory root) for robust growth and health. As a result, Prebiotic delivers more reliable, natural, and comfortable microbiome support.
Plus, the addition of fiber support supports digestion, immune function, fat loss, and more—all features you wouldn’t get from most probiotic supplements.
References
- C Hill, F Guarner, G Reid, et al. Expert consensus document. The International Scientific Association for Probiotics and Prebiotics consensus statement on the scope and appropriate use of the term probiotic.Nat Rev Gastroenterol Hepatol. 2014;11(8):506-514.
- GR Gibson, R Hutkins, ME Sanders, SL Prescott, RA Reimer, SJ Salminen, et al. Expert consensus document: The International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus statement on the definition and scope of prebiotics. Nat Rev Gastroenterol Hepatol 2017;14:491-502.
- HD Holscher. Dietary fiber and prebiotics and the gastrointestinal microbiota. Gut Microbes. 2017;8(2):172-184.
- L Abenavoli, E Scarpellini, C Colica, et al. Gut Microbiota and Obesity: A Role for Probiotics. 2019;11(11):2690.
- C Goswami, Y Iwasaki, T Yada. Short-chain fatty acids suppress food intake by activating vagal afferent neurons. J Nutr Biochem. 2018;57:130-135.
- A Ogawa, T Kobayashi, F Sakai, Y Kadooka, Y Kawasaki. Lactobacillus gasseri SBT2055 suppresses fatty acid release through enlargement of fat emulsion size in vitro and promotes fecal fat excretion in healthy Japanese subjects.Lipids Health Dis. 2015;14:20.
- H Yadav, JH Lee, J Lloyd, P Walter, SG Rane. Beneficial metabolic effects of a probiotic via butyrate-induced GLP-1 hormone secretion. J Biol Chem. 2013;288(35):25088-25097.
- M Wiciński, J Gębalski, J Gołębiewski, B Malinowski. Probiotics for the Treatment of Overweight and Obesity in Humans-A Review of Clinical Trials. 2020;8(8):1148.
- L Aronsson, Y Huang, P Parini, et al. Decreased fat storage by Lactobacillus paracasei is associated with increased levels of angiopoietin-like 4 protein (ANGPTL4).PLoS One. 2010;5(9):e13087.
- GW Tannock, C Taylor, B Lawley, et al. Altered transcription of murine genes induced in the small bowel by administration of probiotic strain Lactobacillus rhamnosus HN001.Appl Environ Microbiol. 2014;80(9):2851-2859.
- J Plaza-Diaz, FJ Ruiz-Ojeda, M Gil-Campos, A Mechanisms of Action of Probiotics (published correction appears in Adv Nutr. 2020 Jul 1;11(4):1054). Adv Nutr. 2019;10(suppl_1):S49-S66.
- A Rivera-Piza, SJ Effects of dietary fibers and prebiotics in adiposity regulation via modulation of gut microbiota. J. Appl. Biol. Jan 2020; 63(2).
- PJ Turnbaugh, M Hamady, T Yatsunenko, et al. A core gut microbiome in obese and lean twins. 2009;457(7228):480-484.
- ES Bliss, E Whiteside. The Gut-Brain Axis, the Human Gut Microbiota and Their Integration in the Development of Obesity.Front Physiol. 2018;9:900.
- H Borgeraas, LK Johnson, J Skattebu, JK Hertel, J Hjelmesaeth. Effects of probiotics on body weight, body mass index, fat mass and fat percentage in subjects with overweight or obesity: a systematic review and meta-analysis of randomized controlled trials.Obes Rev. 2018;19(2):219-232.
- JM Omar, YM Chan, ML Jones, S Prakash, et al. Lactobacillus fermentum and Lactobacillus amylovorus as probiotics alter body adiposity and gut microflora in healthy persons.J Funct Foods. 2013; 5(1): 116-123.
