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In recent years, we’ve discovered increasingly more about the importance of keeping your gut in good shape. You know that a healthy gut can benefit your overall health and wellness from head to toe, helping with everything from inflammation to immunity. And you’ve likely turned to probiotics, prebiotics and other gut-friendly foods to encourage good bacteria to grow. But along the way, you may not have noticed any real changes in your weight.
While gut bacteria has been studied for decades, it’s only now that research is drawing a link between your weight and the bacteria hanging out in your gut. Scientists are discovering that gut bacteria might play an important role in weight loss. What you’re feeding your gut, and what kind of bacteria is thriving there, could either help or hinder your efforts to shed extra weight.
Here’s what you need to know about the connection between your gut bacteria and your ability to lose weight.
Certain bacteria in your gut determine how easy – or hard – it is to lose weight
Your gut bacteria plays an important role in your overall health. The exact types of bacteria that are present, and their genetic makeup, affect your body chemistry. As a result, that bacteria shapes everything from your immune system’s strength to whether or not you develop certain chronic health conditions.
And your gut bacteria directly affect how food gets broken down in your digestive system. Some bacteria are better equipped than others to break down food, digest it and take in its calories. Unfortunately, if you happen to have more of this kind of bacteria, your gut might be helping you gain weight rather than lose it.
A research study published in Cell proves that some gut bacteria really are better for weight loss than others. Individuals who had more of a particular strain – Christensenellaceae – were more likely to be slimmer and have lower BMIs. Those who didn’t have this bacteria were more likely to be overweight, implying that a lack of this bacteria could make shedding extra weight more challenging.
Your genes determine just how much Christensenellaceae bacteria appears in your gut. But, with the right foods, you may be able to increase it.
When researchers altered the levels of Christensenellaceae in overweight mice, increasing the amount of this bacteria in the gut, the mice gained less weight. Doing the same in humans may have a similar effect. 96 percent of the study’s human participants already had Christensenellaceae; a lower amount may be all that’s standing in the way of potential weight loss.
Another research study discovered that having two other types of gut bacteria – Prevotella and Bacteroidetes – can determine just how easily you’re able to lose weight when you diet. Individuals who had more Prevotella in their guts lost 5.1 more pounds of body fat during the 26-week study compared to those who had a prevalence of Bacteroidetes. Having a high Bacteroidetes count could make it more difficult to shed extra pounds.
There’s good news, though: when the study’s participants stuck with a high-fiber, whole-grain diet, they were able to increase Prevotella within the gut. So, if you’re hoping to tap into weight loss-friendly bacteria, you can do so by adjusting what you’re eating.
More diverse gut bacteria could also help weight loss
In addition to having just the right kinds of gut bacteria, you’ll want to aim for diversity. It turns out that there’s also a connection between bacteria diversity and how easily you lose weight.
Having a diverse mix of gut bacteria could help you both maintain a healthy weight and slim down. In one research study, 77 pairs of twins were studied: one twin in each pair was obese, while the other was not. Researchers found that the non-obese twins had different gut bacteria, and they had more diverse strains of bacteria. While the obese twins had very few bacteria species present in their guts, their non-obese siblings had a whole lot of variety.
Diversity in the gut microbiome could play an important role in weight loss because some bacteria are simply better than others at digesting fiber. The better your gut bacteria are at tackling fiber, the more they may be able to help encourage weight loss.
And some types of gut bacteria also affect how fat is absorbed and stored within the body. Some bacteria may be able to suppress fat storage, letting more pass through your digestive system without sticking around. Other strains of bacteria may be more prone to latching onto and storing fat within the intestines, which may make losing weight a bit more difficult.
With a diverse mix of bacteria – or balance in your microbiome – you may be better set up for weight loss success when you stick with a healthy diet.
Your gut bacteria plays a role in your hunger too
There’s one more way that your internal bacteria can shape your weight loss: your appetite.
There are a few different hormones your body produces that are tied to hunger, like leptin, ghrelin and peptide YY (PYY). These hormones tell you that you’re hungry and when you’re full, helping you judge when it’s time to eat. If you happen to produce more hunger hormones, you’ll likely have a bigger appetite, and vice versa.
And your gut bacteria can actually help curb your appetite – if you have the right kinds of bacteria, that is. One research study discovered that fermented foods can increase PYY and glucagon like peptide-1 (GLP-1), two gut hormones that help you feel full, curbing appetite. Another study showed that taking prebiotic supplements can also increase the hormones that tell you you’re full and reduce your appetite. Prebiotics can increase your PYY and GLP-1 hormones, leading to less hunger as the prebiotics get to work fermenting gut bacteria.
So, using fermented foods like probiotics and prebiotics can help both your gut and your hunger levels. With a balance of bacteria, you can lessen the impact of those hunger hormones while you’re trying to lose weight.
Give your gut the right balance of bacteria to make weight loss a little easier
Overall, there’s one big takeaway when it comes to weight loss and your gut: the right bacteria can make all the difference. While you can’t poke around inside your gut like a scientific researcher, you can put their learnings into practice by keeping your gut health in mind when you’re working to lose weight.
The more diverse your gut bacteria is, the more benefits you can experience. A diverse gut tends to be the healthiest gut – and diversity can also make it a bit easier to lose weight. Increasing the ratio of good to bad bacteria may also help you work towards weight loss.
To get just the right balance and diversity in your gut, give these ideas a try: