I have a bit of a running joke with a friend of mine, who has a great personal interest in healthy living. She is always reading, researching, and listening to podcasts. A few years ago, she started to comment on the fact that probiotics suddenly seemed to be everywhere!

The gut-brain connection was making more headlines than ever, and everywhere you turned, there seemed to be a new potential use for probiotics. My friend, noticing this, started to tease that probiotics were the solution for just about everything we talked about. Bad mood? Try probiotics. Bad skin? Try probiotics. Annoying drivers on the interstate? Try probiotics.

Of course, this is all lighthearted, but it’s true that the potential benefits of probiotics and the importance of gut health are really extraordinary! (By the way, the friend I mentioned does take them herself). And, as it happens, they may also play a role in healthy weight loss.

So, before we get to that, what exactly are probiotics? Essentially, they are the live, friendly bacteria that we need for gut health and overall wellbeing. Probiotics exist naturally in the gut, but we all have a different makeup of bacteria in our gut microbiomes, and many factors can cause an imbalance between bacterial species, a proliferation of potentially harmful species, or a problematic lack of diversity.

Probiotic supplements are readily available, and they’re often taken to restore, enhance, or maintain balance in the gut microbiome, which comes with innumerable potential health benefits. Probiotics are also found in fermented foods like yogurt, kombucha, and sauerkraut.

These friendly bacteria have essential roles to play in breaking down and digesting foods, producing nutrients, regulating the immune system, supporting a healthy metabolism, keeping hormones in balance, and regulating mood.

Probiotics have been studied and celebrated over the years for their potential benefits on everything from digestive health and heart health to mood and immune system function. Similarly, an imbalanced gut microbiome has been linked to a number of chronic diseases.

Poor gut health and dysbiosis (an imbalance in the gut microbiome) have also been implicated in obesity, diabetes, and metabolic syndrome, which has led many researchers and practitioners alike to wonder whether probiotic supplements could be helpful in supporting healthy weight loss.

It turns out that the makeup of your gut microbiome can influence metabolism, fat storage, insulin resistance, and weight loss resistance. Recent research has pointed to the potential effects of probiotics on weight loss, from losing belly fat to balancing hunger hormones.

When I work with women who have weight loss resistance– that is, women who are working hard to lose weight but do not seem to be able to– I almost always find some kind of underlying imbalance that is essentially blocking their efforts. It’s frustrating before you figure it out, but the good news is that once we discover an imbalance, we can take the next steps towards reversing it!

Some of the most common imbalances I see underlying weight loss resistance are hormonal imbalances, adrenal dysfunction, and imbalances in the gut microbiome. Often, it’s a combination of these imbalances, which makes perfect sense because really, all of these areas are connected!

But for now, let’s focus on the connection between gut bacteria and weight. If you’ve been struggling to shed excess weight or belly fat, or to maintain a healthy weight, this just might be the missing link.

Gut health and weight

There’s been some really interesting research showing differences in the gut microbiomes of obese individuals compared with the gut microbiomes of healthy individuals.

This doesn’t necessarily mean that an imbalanced gut microbiome is entirely responsible for obesity! It’s much more likely that there’s a complex interplay of factors here, and the link between gut health and a person’s weight actually goes both ways (for example, research has shown that when overweight individuals lose weight, the diversity of their gut bacteria improves).

One thing we always want to look at is why someone’s gut bacteria might be imbalanced. If this is a common underlying factor behind obesity or weight loss resistance, what’s causing the disruption in the first place?

The community within the gut– and the plethora of species that inhabit it– is influenced by everything from stress to diet to use of medications.

There are a bunch of factors that have been found to play a role in the development of our gut microbiomes when we’re born and in infancy and childhood, but the microbiome continues to change and be shaped throughout our lifespan. In fact, we make choices every day that can impact the critters in our guts!

What’s especially interesting is that it’s not just that lean and obese animals have different patterns in their gut microbiomes. There have been some fascinating animal studies showing that when the gut bacteria from an obese mouse is transplanted into the gut of a mouse with a previously healthy weight, the healthy mouse actually gets fat!

Gut microbiota transplants from healthy to obese rats have also been able to significantly reduce both obesity and insulin resistance.

In humans, we still need to see more research in this area, but we know that microbiota transplants can improve insulin resistance and the diversity of the gut microbiome.

A lack of diversity in the gut microbiome is linked to inflammation, which is a big problem when it comes to weight gain, obesity, and chronic disease (including metabolic syndrome and type 2 diabetes).

Probiotics have been shown to help reduce systemic inflammation, which may be one of the ways in which they might help support healthy weight loss.

Leaky gut is another digestive system concern that’s associated with both inflammation and weight gain. Research on mice with metabolic syndrome has shown that probiotics may significantly reduce both inflammation and leaky gut.

Probiotics and Weight Loss

There’s no question that a healthy gut has a role to play in healthy weight! So, can probiotics help with weight loss?

Studies have had mixed results, but there’s been some promising research showing us where and how probiotics may have a positive effect on weight loss, metabolism, and fat storage.

One thing I’ll make clear is that if you’re taking probiotics but you’re also eating a diet that’s disruptive to your gut, your hormones, and your metabolism, you might not see any results! In other words, probiotics are not magic pills.

But, in conjunction with a healthy and personalized diet and lifestyle plan, probiotics might be helpful to support healthy weight loss in some people.

Some probiotics, including those from the Lactobacillus family, have been found to reduce the absorption and storage of fat from food. In other words, probiotics might be able to help the body use more fat for fuel, and store less of it in the body.

Probiotics may also help to regulate appetite through their impact on hormones related to satiety.

Research has shown that some Lactobacillus family probiotics might be able to help with weight loss, including loss of the stubborn belly fat that drives so many of us crazy.

Probiotics may also have a role to play in the prevention of weight gain, and may contribute to a healthy metabolism.

Many people associate weight loss with metabolism, but what not everyone knows is how many different factors go into the health of your metabolism. It’s not all about age or genetics!

Poor gut health and an imbalance in the microbiome are associated with a damaged metabolism and metabolic syndrome, which may be in part because of the relationships between gut bacteria and insulin production, hormonal balance, and inflammation.

Should you take probiotics for weight loss?

Probiotic supplements may help to support a healthy gut, hormonal balance, and maybe even healthy weight loss. As with any supplements, it’s best to talk to your practitioner before starting to take anything new. With that in mind, here are my suggestions if you’re looking into taking probiotics for weight loss.

First of all, there are many, many different probiotic supplements available, and it can be overwhelming to know which kind to take! There are different species, different strains, different quantities… not to mention the number of different brands on the market today.

Most probiotic supplements contain strains of either Lactobacillus or Bifidobacterium, and sometimes both. There are resources out there that really break down the many different strains of available probiotics in detail, and this is where it can get really confusing. At this point, we don’t have enough available research to determine exactly which bacterial strains are most helpful for any condition or any individual.

So, when sourcing a probiotic supplement, I suggest focusing on the quality and the trustworthiness of the maker. You can always ask your functional medicine practitioner for their recommendations as well.

But, whether or not you decide to take probiotics, remember not to treat them like weight loss pills! If probiotic supplements are helpful along your weight loss journey, it’s because they’re helping to support your gut health, which has far-reaching benefits. So, help them (and yourself) along by supporting your gut health in other ways as well.

Fermented foods are rich in probiotics, and great for gut health! Try incorporating more fermented foods like yogurt, sauerkraut, kombucha, and kefir into your diet. 

There are a number of things that can contribute to an imbalance between healthy and unhealthy bacteria in the gut. Whether or not you choose to take probiotics, I would always recommend looking into any diet and lifestyle factors that might be hard on your gut health.

Some of the common factors that can contribute to dysbiosis are chronic stress, sugar and refined carbohydrates, processed foods and dietary toxins, and the use of certain medications including antibiotics and NSAIDs. Infections, including chronic, low-grade infections, can also disrupt the gut microbiome. So can a diet that is too low in healthy, fermentable fiber.

Some of the things we can all do to support a healthy gut for healthy weight loss include removing processed foods and refined sugar from the diet, making sure to get lots of fiber, treating any underlying infections, and taking steps to address and manage stress.

The effects of probiotics on weight loss might be modest, but the body of research that demonstrates the crucial role of gut health in weight management is significant!

So, I wouldn’t rely on a probiotic supplement to do all the work when it comes to weight loss. But, if you have been following a healthy diet, exercise, and lifestyle plan, and you are still struggling with weight loss resistance, an imbalance in gut bacteria may be an important piece of the puzzle. And if that’s the case, probiotics, as one part of a well-rounded approach, might be able to help get you back on track!