Probiotics for weight loss: does it work and what does the research say?

Nearly everyone would love to get rid of a few (or a dozen) unwanted kilos. Preferably without much effort, diets and so on... Oh, for example with the help of some magic capsule. And it could even be full of bacteria.

Probiotics for weight loss is a hot topic. But let me cool your enthusiasm right away. Contrary to all the latest findings of American scientists (which are mostly out of context and twisted) - the magic capsule for weight loss does not exist (sorry, me too). Nevertheless, probiotics do have something to say on the subject of weight loss.

See also:

• Best weight loss pills
.
• What is a probiotic
• What is a prebiotic
• What is a synbiotic
• What is a psychobiotic
• Where to find natural probiotics
• The best probiotic for the gut
• Best probiotic for gynecology
• Best probiotic for pregnant women
• Which probiotic is best

Probiotics and weight loss

The probiotic bacteria that naturally inhabit your gut are true miracle workers. They look after you as well as they canand:

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• help you digest and assimilate nutrients from food,
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• produce substances that destroy pathogens,
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• interact with pathogenic microbes to colonise the intestines and genitourinary tract,
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• strengthen the intestinal barrier by producing, among other things, sodium butyrate,
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• they can combat diarrhoea, constipation, flatulence and other digestive complaints,
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• influence the production of neurotransmitters, improving your mood,
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• stimulate your immune system, improving immunity,
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• some of them help fight inflammation,
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• may help regulate your metabolism,
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Well, that's right: metabolism. In recent decades, the beneficial effects of probiotics have been studied for virtually all ailments, including those of civilisation. And one of the biggest challenges of our time is obesity and metabolic syndromes, such as insulin resistanceand.

An increase in the ratio of Firmicutes to Bacteroidetes is associated with low-grade inflammation and an increased ability to obtain energy from food. Interestingly, a high-fat diet promotes this phenomenon, adds pharmacist.

Since microscopic bacteria regulate so many processes in your body, can they also help you lose weight?"

Probiotics for weight loss - what the internet says

It is certainly worthwhile for the diet of weight-loss sufferers to include natural probiotics, which are found in food. Sauerkraut or cucumbers are valuable sources not only of these bacteria, but also of fibre and vitamins that help with weight loss. Natural yoghurt or kefir are also sources of probiotics and great snacks for those on a diet.

However, the internet has gone crazy about probiotic supplements for weight loss. On the web, you can read, among other things, unscientific claims that probiotics reduce the absorption of kilocalories or prevent the absorption of fat and its accumulation in the flanks.

Ten times, the narrative is that probiotics are a great way to lose weight.

Often the narrative is as if probiotic bacteria can eat away any caloric surplus and, on top of that, inhibit the rise in cholesterol after every packet of chips you eat to an episode of your favourite TV show.

Of course, a world where munching on chocolate bars, biscuits, crisps and a burger from a well-known chain every day doesn't affect your health would probably be tempting. But perhaps let's come down to earth after all...

Probiotics for weight loss - what the research shows

Does gut microflora affect body weight at all? Yes. A study involving 333,353 children was conducted in 2019. Its findings suggest that those who received antibiotic treatment or gastric acid suppressants (i.e. drugs that deplete the microbiota) during the first two years of life were more likely to be obeseand.

Additionally, this risk increased with the frequency of taking these drugs and their combinationsand.

And what about adults? It is estimated that the prevalence of overweight and obesity in the population is now as high as 39%. This is almost three times more than in the 1970sand. Changes in the gut flora, caused by a highly processed diet, overconsumption of antibiotics (including those found in food) and a low-activity lifestyle .

A 2019 review of studies looked at the effects of probiotics on lipid metabolism and glycaemia. Twelve research studies were included in the review. The conclusions wereand:

• 10 studies reported weight loss among participants taking probiotics (compared to placebo groups),
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• 11 studies showed an effect of taking probiotics on reducing body mass index (BMI),
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• probiotics reduced waist circumference by an average of 1.2 cm among participants in 8 studies,
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• 9 studies also examined body fat percentage, and 6 of these studies confirmed a reduction in this indicator among participants taking probiotics,
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• 7 studies confirmed a reduction in total cholesterol under the influence of taking probiotics,
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• none of the studies showed an effect of probiotics on triglyceride concentrations in the body,
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• in 6 papers, a positive effect of probiotic intake on fasting glucose concentrations was confirmed,
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• Several scientific papers have also confirmed the effect of probiotics on insulin and the insulin resistance index (HOMA-IR).

Interestingly, based on this analysis, it was found that the best effects in the majority of cases were recorded with single-strain formulationsand.

This definitely sounds encouraging. But wait and look at the numbers carefully.

Another 2019 meta-analysis involving people with metabolic diseases (including overweight - but not obesity), confirms the effect of probiotics on weight loss, to the extent thatand:

• average weight loss - 0.94 kg,
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• average reduction in waist circumference - 1.31 cm,
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• average decrease in fat mass - 0.96 kg,
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In most cases, participants took probiotics for about two weeksand. You might think to yourself: a kilogram in a fortnight - not bad! But what's next? In 2020, Polish researchers conducted a review of clinical trials showing that longer probiotic supplementation was associated with greater weight lossand.

The period of supplementation in the studies considered lasted up to 12 weeks. The authors highlighted several interesting aspects of the effect of probiotics on the treatment of obesityand.

Firstly, they looked at the metabolic products of probiotics, namely short-chain fatty acids (SCFAs). Their role in obesity is very unclear: on the one hand, their concentrations have been shown to be higher in obese people; on the other hand, some studies suggest that they may contribute to weight loss.

However, the mechanism of action of SCFAs on metabolism is not well understood and is based on conjecture. In any case, so is the mechanism of action of the probiotic bacteria themselvesand.

Firstly, the probiotic bacteria themselves are not known.

Secondly, in contrast to the review of studies I wrote about above, this one suggests that for weight loss, probiotics multi-strain mixturesand work better, which seems to confirm how little well-established knowledge we currently have about probiotics.

Thirdly, the authors cite a study of 19 teenagers, the results of which suggest that probiotics may have caused... weight gainand. How is this possible? Well, the authors speculate that teenagers may have underestimated the seriousness of the situation and... snacked. This, however, shows that probiotics certainly won't 'eat' your calorie surplus.

Can probiotics... eat fat?

And what is it with this 'fat eating' by probiotic bacteria? In 2015, an interesting study was conducted on a group of 20 healthy men aged 18-30. They consumed a high-fat, high-energy diet for four weeks. However, in addition to this, one group also took probioticsand. After 28 days, the participants' metabolic parameters were checked. The conclusions were as follows:

• All men gained weight - in the group without probiotics by an average of 2.30 kg, and in the group with probiotics by an average of 1.42 kg.
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• All men increased body fat - in the control group by an average of 1.29 kg and in the group consuming probiotics by an average of 0.63 kg.
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• There were no differences in insulin sensitivity in either group.
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These results suggest that probiotics may slow down weight gain with a high-fat diet, but do not eliminate it completely. Consuming excess fats and kilocalories will still make you fat - there are no miracles, you can't cheat physics.

Finally, let's look at another aspect of weight loss, which is time. Two-, four- or even 12-week treatments are nice if you have a maximum of a few kilos to lose. However, if you want to get rid of more excess weight or obesity, a longer treatment would be appropriate.

Studies on the effects of long-term probiotic intake with humans are scarce, however. One reason may be that long-term probiotic supplementation can lead to bacterial overgrowth, known as SIBO syndrome .

A 2016 scientific article cites a study showing the effects of taking the strain L. rhamnosus CGMCC 1.3724 for 12 and 24 weeks. Participants were divided into two groups: those taking probiotics and those taking placebo.

In addition, they were all expected to follow a reduction diet - a very important aspect of this study. The effect on participants' body weight varied according to gender and was as follows:

As you can see, the rate of weight loss - as with standard diets - was highest in the first 12 weeks, then slowed down. This is a natural phenomenon when so-called  metabolic adaptations take place, and you need to redetermine your caloric requirements, because less weight=less demandand.

Probiotics for weight loss - research findings at a glance

Scientific research makes it clear: probiotics have an impact on your body weight, but they are not a magic pill for weight loss. You won't lose much weight from taking probiotics alone - unless your goal is to lose a kilo or two at mostand.

Probiotics can instead be a valuable support in weight loss, with the right diet and increased physical activity. They can then help regulate your metabolism, lower your lipid profile and improve your glycaemiaand.

However, if you follow a diet that is too high in calories and fat, probiotics alone will not protect you from weight gain .

See also:

• Probiotic before or after an antibiotic?
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• When to use probiotics?
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• When are probiotics harmful?
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What probiotics can affect weight loss?

Probiotics vary in their properties depending on the specific genus, species and strain. In the most general terms, Lactobacillus and Bifidobacterium can be said to be effective in the context of weight loss, but this is basically like saying nothing.

Reviewing the research on probiotics for weight loss, one comes across dozens of different strains, most of which... do not produce the effects they are claimed to. So which ones are really effective?

Positive results were given by mixtures of strains, among others:

• Lactobacillus acidophilus La5, Bifidobacterium BB12 and Lactobacillus casei DN001,
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• Lactobacillus curvatus HY7601 and Lactobacillus plantarum KY1032,
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• Lactobacillus acidophilus LA-14, Lactobacillus casei LC-11, Lactococcus lactis LL-23, Bifidobacterium bifidum BB-06, Bifidobacterium lactis BL-4 (Danisco),
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• Lactobacillus salivarius UBLS-22, Lactobacillus casei UBLC42, Lactobacillus plantarum UBLP-40, Lactobacillus acidophilus UBLA-34, Bifidobacterium breve UBBr-01, Bacillus coagulans Unique IS2.
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One of the most extensively researched probiotics that shows promise when it comes to weight loss is the species Akkermansia muciniphila. These bacteria have the ability to produce acetate, propionate and butyrate, or short-chain fatty acids (SCFAs). Researchers have been able to link obesity to lower numbers of these bacteria in the gutand.

Preliminary research suggests that these bacteria may be helpful in the prevention and treatment of obesity. However, I must mention that most of these have been conducted on animalsand.

"Examples of postbiotics are:

• SCFA (acetate, propionate and butyrate), 
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• enzymes, 
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• peptides, 
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• vitamins, 
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• tachoic acids, 
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Propionate and butyrate can reduce body weight and obesity by improving the expression of gluconeogenesis genes. Bacteroidetes produce mainly acetate and propionate, while Firmicutes produce butyrate," explains pharmacist.

Lactobacillus gasseri and weight loss

With Lactobacillus gasseri there is quite a bit of fun to be had on the subject of weight loss. According to research, strains SBT2055 and BNR17  can be helpful, but within this species there are also strains that can cause weight gain . This is another reason why it's a good idea to carefully read the formulations of the products you want to supplement...

Lactobacillus rhamnosus and weight loss

When it comes to weight loss Lactobacillus rhamnosus CGMCC1.3724 it shows a positive effect, but seems to only like ladies, on whom - according to the study - it seems to work much more effectively than on menand. Just the picky type.

Interestingly, another strain of the rhamnosus species - GG may be helpful in treating gestational diabetes, but taken alone, it was not associated with weight loss in most studies .

Probiotics in a weight loss diet - a nutritionist's opinion

Clinical nutritionist Julia Skrajda explains:

Probiotics can be useful for us when losing weight, especially if we have a problem with increased waist circumference. These bacteria help us to stimulate the microbiome in such a situation.

Probiotics can help us to lose weight.

The short-chain fatty acids they produce help us regulate incretin hormones (GLP-1), stimulate insulin secretion, delay gastric emptying, and reduce glucagon secretion. The main bacterial strains I recommend for reduction are: Lactobacillus Rhamnosus GG and Bifidobacterium Lactis (1010 CFU) - especially in combination.

What's more, high levels of protein fermentation by gut bacteria have been linked to increased genotoxicity, which may be associated with intestinal cancers, adds pharmacist.

How long to take probiotics for weight loss?

For the time being, probiotics have not been officially recognised as a treatment for obesity. So there are no specific guidelines as to how long you should supplement them for weight loss. The only thing that can be relied on is the duration of the scientific studies. Most of them involved a period of 8 to 12 weeksand.

See also:

• Butyric acid
• Sodium butyrate

Summary