Do Probiotics Help You Lose Weight? A Review of the Research

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    Do probiotics help you lose weight? We review the research on the role of probiotic supplements and the gut microbiome in weight loss.

    When it comes to probiotics, one big question that has come up lately is: “Do probiotics help you lose weight?”

    Probiotics seem to be everywhere these days. While they used to only be promoted as the main ingredient in gut-supporting yogurts, their use has since exploded. You can find probiotics in everything from cereals and smoothies to shampoos and skincare.

    Along with the expansion of their use in products, the research on the benefits of probiotics has grown as well. Probiotics are no longer “just” for the gut. They are now being studied for a variety of potential benefits including the support of immune, skin, and metabolic health. Probiotics may also have an influence on body weight.

    If body weight caught your attention, you came to the right place! Let’s dig into the current research in order to provide insights into the question: “Do probiotics help you lose weight?”

    Gut bacteria and body weight regulation

    Your colon, also called the large intestine, is home to trillions of microbes. These include bacteria, yeasts, and other critters that make up your gut microbiome. But there’s no need to fear! These gut bugs are not harmful when in balance, and they actually play really important roles in many areas of health.

    One aspect of health that gut bacteria can have an impact on is body weight regulation. The microbes in the gut help break down the food we eat and produce energy as a result. Certain microbes have been found to be more efficient at this process. Some research has even correlated a microbiome that is rich in certain microbes with a healthy body weight.

    The gut microbiome also plays a role in triggering hormones that control hunger and fullness, which can impact body weight. Energy metabolism may also be influenced by the microbes in the gut.

    When bacteria in the gut break down certain fibers, they make short-chain fatty acids (SCFA) such as butyrate. These special fatty acids may actually help support a healthy oxidative status, which could result in a healthy body weight.

    Therefore, it does appear that a healthy gut microbiome may play a role in body weight regulation. However, additional randomized controlled trials need to be done in order to draw conclusions and examine the effect of probiotics on weight overall. For now, the science shows that probiotics mainly support gut health, immune function, and regular bowel movements. The next question is: Do probiotics help you lose weight?

    How probiotics influence body weight regulation

    You may have seen images of a larger-bodied mouse next to a smaller-bodied mouse circulating in the news back in 2013. This was in response to a novel research study to help understand weight and the microbiome.

    This study suggests that the gut microbiome can potentially be altered to influence body weight. While it may not be necessary to do a “fecal transplant” to influence body weight, perhaps probiotics contribute?

    A variety of animal studies have found that probiotics can prevent weight gain in response to a high-fat diet. The main types of probiotics used in these studies were Lactobacillus and Bifidobacterium strains.

    A study in humans found that taking a probiotic blend helped reduce body fat gain from a high-fat and high-calorie diet.

    While the evidence seems to indicate that probiotics may have a benefit in maintaining healthy body weight, more rigorously designed studies need to be done before any conclusions are drawn. What about probiotics supporting weight loss?

    Can probiotics help you lose weight?

    As weight and health continues to be a hot topic in research, much of the research on probiotics and body weight has focused on this area. One study found that a probiotic strain of Lactobacillus rhamnosus led to weight loss when combined with 12 weeks of moderate caloric restriction. In another study, a probiotic strain derived from kimchi called Lactobacillus sakei was found to be beneficial for weight loss.

    Kimchi isn’t the only fermented food of note. Researchers gave fermented milk that contained a probiotic strain called Lactobacillus gasseri to adults and saw a reduction in “abdominal adiposity” (fat around the midsection).

    Interestingly, the benefits found in these trials were not strain-specific, so it’s possible that different strains of Lactobacillus may be useful. More research would be needed to see if a variety of probiotic strains could lead to similar results.

    It’s always important to review all available evidence when looking at research findings. There was a systematic review published in 2017 that analyzed 15 studies that looked at the effects of probiotics on body weight, BMI, and other factors in people who were overweight.

    The review found that there was a significantly larger reduction in body weight, BMI, and fat percentage. But not a significant reduction in fat mass. Fat mass is the weight of fat on the body, so it is interesting that the other markers were significantly reduced. Either way, a review of the evidence found that probiotics significantly reduced body weight.

    Besides taking probiotics, there may also be a role for prebiotics and body weight. Prebiotics are a type of fiber that resist digestion. Instead of being broken down by acids or enzymes in our digestive tracts, prebiotics pass through intact and are fermented by gut microbes. Research suggests that since prebiotics can influence the microbiome, they may play a role in body weight regulation.

    There is so much exciting potential for additional research to illuminate the connection and fully understand the relationships between weight and probiotics in order to support weight management. In the meantime, healthy lifestyle changes are the best options to consider for weight management. Some of these changes can include eating nutrient-dense foods, getting enough sleep, adequate hydration, and regular exercise.

    Can probiotics help flatten your stomach?

    If probiotics lead to weight loss, then they could potentially flatten your stomach or midsection (remember the abdominal adiposity study?). But the location of body fat is mostly due to genetics and hormones, so it’s hard to know where weight loss would occur with probiotic intake from fermented milk.

    Additionally, probiotics may reduce bloating, which could lead to less visible signs of bloating and a flatter stomach. Also adding in digestive enzymes into your supplement regimen can help relieve gas or indigestion after meals by supporting proper breakdown of the foods being consumed. Prebiotics can support healthy digestion in general, as well.

    The best way to support weight loss and a healthy abdomen is through lifestyle changes that include proper diet, exercise, adequate sleep, and hydration.

    Potential side effects and risks of probiotics for weight loss

    Probiotics are generally considered to be safe when used by healthy people. It is possible that some people may experience a brief or temporary increase in gas or bloating, especially when first taking probiotics, while the microbiome adjusts.

    Probiotics support the gut microbiome however the best way to support weight loss is through a plan that includes a nutrient dense diet, regular exercise, hydration, and adequate sleep. Talk to your doctor to come up with the best plan for you.

    How to take probiotics

    When taking probiotics, it’s best to take them as stated on the label or as directed by your healthcare provider.

    As you can see, there were many different probiotic strains used in the studies we discussed, so choosing a blend of multiple strains of probiotics may be best.

    As for how long to take probiotics, many of the studies mentioned above lasted for at least 12 weeks.

    With regard to weight loss, there is not enough evidence to draw conclusions or make recommendations for probiotics and weight loss at this point. Additional research is needed overall. The best way to support healthy sustainable weight loss is through a balanced plan that consists of a nutrient dense diet, adequate hydration, regular exercise, and adequate sleep.

    When is it best to take probiotics

    You should follow the label instructions to help you determine when to take probiotics in general. Some may recommend taking the probiotic supplement with or without food. Here are more details about the best time to take probiotics.

    Final takeaways

    A healthy microbiome can have a lot of benefits to your health. One of those benefits is the potential to support a healthy gut microbiome. The gut microbiome likely plays a role in regulating metabolism and fullness in the body. Preliminary studies show that supporting the microbiome by taking probiotics could support body weight and may even help with weight loss. However, more research and rigorously designed human trials are needed before any conclusions can be drawn.

    The studies mentioned above did not include other lifestyle factors because they wanted to only study the effects of taking probiotics on body weight. However, it’s important to note that a plan to support a healthy body weight should include nutrition, exercise, and other lifestyle changes.

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    Dr. Carla Montrond Correia ND, CNS
    Medical Content Manager
    Dr. Montrond-Correia is a licensed naturopathic physician and a certified nutrition specialist (CNS). She holds degrees from University of Bridgeport, Georgetown University, and University of Saint Joseph, and supplemented her education with internships in the health and wellness space. She's focused on research, herbal medicine, nutrigenomics, and integrative and functional medicine. She makes time for exercise, artistic activities, and enjoying delicious food.
    Our Editorial Staff
    Freelance Contributor
    The Care/of Editorial Team is made up of writers, experts, and health enthusiasts, all dedicated to giving you the information you need today. Our team is here to answer your biggest wellness questions, read the studies for you, and introduce you to your new favorite product, staying up to date on the latest research, trends, and science. Each article is written by one of our experts, reviewed both for editorial standards by an editor and medical standards by one of our naturopathic doctors, and updated regularly as new information becomes available.