Fact Checked by Dr T Moran, PHD
The human body is home to a vast array of bacteria, and while some may be harmful, others play a crucial role in maintaining our overall health. Probiotics, also known as friendly bacteria, can be found naturally in fermented foods like yogurt or taken in supplement form. Many people turn to probiotics to replenish their gut with good bacteria, particularly after a course of antibiotics. [1] Apart from aiding digestion and supporting the immune system, probiotics have also been associated with weight loss. In this article, we will explore the connection between gut bacteria and weight loss, the potential impact of probiotics on metabolism, [2] and whether probiotic supplementation can effectively contribute to shedding those extra pounds.
The likelihood is that for most people there are more effective weight loss aids out there, as ultimately everything does come down to how many calories you consume, [3] however, your gut microbiome can effect everything from which food you burn as energy and even which foods your body craves. Effective appetite supressants, stimulants and even thermogenics are probably going to do more for weight loss than probiotics in 90% of cases. [4]
The Role of Gut Bacteria in Weight Loss
The gut is home to trillions of microorganisms, collectively known as the microbiome. [5] These bacteria work symbiotically to perform various functions, including breaking down nutrients, metabolizing medications, protecting against harmful pathogens, maintaining gut integrity, and influencing the immune system.[6] When the balance of bacteria in the gut is disrupted, a condition called dysbiosis occurs. Dysbiosis has been linked to digestive disorders, allergies, and even neurological conditions. [7]
While the precise relationship between gut bacteria and weight is still not fully understood, research has shed some light on the topic. A study conducted on twins revealed that obese individuals had less diversity in their gut bacteria compared to their lean counterparts. [8] Other studies have indicated that certain strains of bacteria may slow down weight gain, reduce waist size, and potentially aid in weight loss. However, it is important to note that not all researchers have been able to establish a direct correlation between gut bacteria and weight and there are an awful lot of negative results in this field as well as the positive ones. [9,10]
The Impact of Gut Bacteria on Metabolism
Scientists generally agree that gut bacteria have some influence on metabolism. They contribute to the production of essential vitamins such as vitamin K, folate, biotin, and vitamin B12. [11] Additionally, they play a role in the absorption of minerals like magnesium, calcium, and iron. Gut bacteria also assist in the breakdown of carbohydrates and the fermentation of dietary fibers, resulting in the production of short-chain fatty acids (SCFAs). [12]
Studies conducted on animals have suggested that SCFAs can enhance the body's ability to tolerate sugar, improve energy utilization, promote satiety, and suppress appetite. However, further research is needed to determine if these findings translate to humans. Nonetheless, the evidence so far indicates that gut bacteria play a significant role in metabolism and energy balance. [13]
For context your microbiome can in fact effect the thermic effect of food or diet induced thermogenesis (that's how many calories it takes you to break down your food). Thus effecting your metabolism. [14]
And because your gut microbiome can how much energy you have, the latter is important in ways that you may not realize. For example your none excersise activity thermogenesis or NEAT often drops rapidly whilst dieting. This is simply how much you move around and how many calories you burn without deliberately working out. [15]
So, if you're body knows you're in a calorie deficit, [3] AKA less calories than you need to maintain your current weight, you will subconciously move less. This is one of the reason stimulants like coffee often aid weight loss. [16]
So aside from just altering how you break down calories, probiotics can help you lose weight by impacting other factors. Although as we stated, stimulants can be more effective at combatting a drop in NEAT and lipase inhibitors [17] (fat binders) or appetite suppressants can have a slighlty more pronounced impact on these specific mechanisms than a probiotic supplement. [18]
Probiotics and Weight Loss: Separating Fact from Fiction
Given the potential impact of gut bacteria on weight regulation, researchers and individuals alike have turned to probiotics as a potential solution for weight loss. Probiotics offer a convenient way to introduce beneficial bacteria into the gut, with the hope of influencing weight management. However, it is important to note that while probiotics have been shown to provide numerous health benefits, [19] clear evidence supporting their efficacy in weight loss is still lacking.
Several studies have been conducted to investigate the effects of probiotics on weight loss, and the results have been mixed. Some studies have demonstrated positive effects, while others have shown no significant impact on body weight. It is crucial to consider the specific strains of bacteria used, the dosage, the duration of supplementation, and individual variations when interpreting these findings. [2,8,9,13]
The Potential of Probiotics for Weight Loss
Although the evidence is not yet conclusive, certain strains of probiotics have shown promise in aiding weight loss. Lactobacillus and Bifidobacterium, in particular, have been widely studied and have demonstrated positive effects in reducing body weight and promoting fat loss. [20,21] These strains are commonly found in various probiotic supplements and fermented foods.
A systematic review of randomized clinical trials examining the effects of probiotics and synbiotics on weight loss in overweight and obese individuals found that out of the 27 studies analyzed, 23 reported positive effects on weight reduction. [22] The intake of probiotics or synbiotics, either in isolation or combined with lifestyle modifications, such as energy restriction and increased physical activity, resulted in significant weight reductions over an average period of 12 weeks. [23] It is worth noting that the specific strains used in these studies were primarily from the Lactobacillus and Bifidobacterium genera, further supporting their potential in weight management.
Which Probiotics are Best for Weight Loss?
The mechanisms through which probiotics may contribute to weight loss are still being explored. One proposed mechanism is the alteration of gut microbiota composition, specifically the balance between Bacteroidetes and Firmicutes. [24] Individuals with obesity tend to have a higher proportion of Firmicutes and a lower proportion of Bacteroidetes compared to those with normal weight. It is believed that this imbalance may affect energy extraction from food and promote energy storage as fat.
Probiotics may also influence the production of certain hormones involved in appetite regulation. Research suggests that an altered gut microbiota can lead to suppressed production of fasting-induced adipose factor (Fiaf), [25] resulting in increased triglyceride storage and reduced release of satiety hormones such as glucagon-like peptide 1 (GLP-1) and peptide YY (PYY). [26] By restoring gut microbiota balance, probiotics may help modulate these hormonal signals and promote feelings of fullness and satiety.
Other Considerations With Probiotics And Weight Loss
Lastly there are a couple of other things to consider when it comes to probiotics and weight loss:
1. Probiotics can reduce bloating, making you look slimmer without actually contributing to fat loss [27]
2. High fiber and high protein diets have been shown to be effective for weight loss, but can often cause gastric issues, probiotics can help reduce the unpleasant side effects allowing people to stick to these diets more effectively, creating corralations that are not specifically the probiotics causing weight loss. [28] Keep in mind that different strains are good for better marconutrient breakdowns. One probiotic strain could aid fat breakdown vs a probiotic good for protein digestion.
3. Probiotics can sometimes cause gastric issues, increasing regularity and giving the illusion of short term weight loss. [29]
4. Probiotics are generally good for the overall health of individuals with poor diets, this isn't directly related to weight loss, but is of course a secondary benefit.
5. Probiotics can counter the negative effects of common appetite suppressants like glucomannan, which can cause discomfort. Glucomannan works by swelling 50X larger when in the stomach, simulating fullness and works well when taken 30 mins to an hour before eating for individuals that struggle with portion control. [30] Some people have an issue with the swelling causing discomfort for a few hours and probiotics can counter this issue as glucomannan is a good food source for many probiotic enzymes. [31]
Incorporating Probiotics into a Weight Loss Plan
While probiotics alone may not be a magic solution for weight loss, they can be a valuable addition to a comprehensive weight management plan. Here are some practical tips for incorporating probiotics into your routine:
Choose a reputable probiotic supplement: Look for products that contain specific strains of Lactobacillus and Bifidobacterium, as these have shown potential in weight management. Check for third-party testing and quality certifications to ensure the product's efficacy and safety.
Consume probiotic-rich foods: Incorporate fermented foods like yogurt, kefir, sauerkraut, and kimchi into your diet. These foods naturally contain probiotic bacteria and can contribute to a healthy gut microbiota.
Maintain a balanced diet: Probiotics work in synergy with a healthy diet. Ensure that you consume a variety of nutrient-dense foods, including fruits, vegetables, whole grains, lean proteins, and healthy fats.
Stay physically active: Regular exercise not only supports weight loss but also promotes overall gut health. Engage in activities you enjoy and aim for a combination of cardiovascular exercise and strength training.
Consult a healthcare professional: If you are considering probiotic supplementation as part of your weight loss journey, it is advisable to consult a healthcare professional or registered dietitian. They can provide personalized recommendations based on your specific needs and goals.
Can Probiotics Help You Lose Weight? Conclusion
While the research on the connection between probiotics and weight loss is still evolving, there is growing evidence to suggest that certain strains of probiotics, particularly Lactobacillus and Bifidobacterium, may have a positive impact on weight management. The potential impact of these isn't as high as some other weight loss aids, however they are definitely able to contribute in some meaningful way. Especially for individuals with compromised microbiomes, such as those post anti biotics or in certain life phases. For example there are certain strains that would have increased probiotic benefits for menopausal women. [32]
These beneficial bacteria contribute to a balanced gut microbiota, support metabolism, and influence hormonal signals related to appetite regulation. However, it is important to approach probiotics as part of a holistic weight management plan that includes a balanced diet, regular exercise, and consultation with healthcare professionals. By combining these strategies, individuals may enhance their chances of achieving sustainable weight loss and overall gut health.
About Fact Checker
Dr Moran PhD. joined Center TRT from the Global Obestiy Prevention Center. He has studied obesity and the biologicial and neurochemical mechanisms behind fat storage and weight loss. With over 30 years of experience in the field he has a wealth of knowledge in the field. View Profile
References
1 - https://www.ncbi.nlm.nih.gov/search/research-news/4460/
2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8470858/
3 - https://www.niddk.nih.gov/bwp
4 - https://ods.od.nih.gov/factsheets/WeightLoss-HealthProfessional/
5 - http://www.niehs.nih.gov/health/topics/science/microbiome/index.cfm
6 - https://ods.od.nih.gov/factsheets/Probiotics-HealthProfessional/
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17 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4464291/
18 - https://www.niddk.nih.gov/health-information/weight-management/prescription-medications-treat-overweight-obesity
19 - https://www.nccih.nih.gov/health/probiotics-what-you-need-to-know
20 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8540110/
21 - https://pubmed.ncbi.nlm.nih.gov/28643627/
22 - https://pubmed.ncbi.nlm.nih.gov/26032481/
23 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7465252/
24 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7285218/
25 - https://pubmed.ncbi.nlm.nih.gov/16272564/
26 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7146451/
27 - https://pubmed.ncbi.nlm.nih.gov/15220670/
28 - https://pubmed.ncbi.nlm.nih.gov/29769003/
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30 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4401854/
31 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6392846/
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