Probiotics are types of live bacteria and yeast (similar to the ones already living in your gut) that you can digest. They’re found in certain foods like some yoghurts and other fermented foods like kimchi, kombucha, sauerkraut, and kefir. You can also get probiotic supplements — although it’s not clear yet which microbes and doses are the most helpful.
Probiotics are a type of bacteria that are thought to have a wide range of health benefits. They're found in certain types of food and, when digested, help restore balance in your gut microbiome.
There are dozens of different groups of probiotics, and very little is known about them. The most popular groups are Lactobacillus and Bifidobacterium — which are commonly advertised on yoghurt. Yet each group is made up of numerous species and each species is made up of even more strains. What’s more, each species within a group can have different effects on your body.
Prebiotics aren't the same as probiotics. They're a type of fibre found in food. Although you can’t digest prebiotics, they’re eaten by the healthy microbes in your gut, allowing them to grow.
Although research is still at an early stage, and there is not much evidence to support many of the claims made around probiotics, many experts agree that they are beneficial to your health.
However, there is now more and more solid evidence showing that probiotics do have a positive impact on two issues: Irritable bowel syndrome (IBS) and diarrhoea caused by antibiotics.
How probiotics help with IBS
Research has shown that there's a strong link between an upset microbiome and IBS. Taking certain probiotics helps restore balance in your gut, reducing certain symptoms of IBS, including bloating and constipation.
How probiotics help with diarrhoea caused by antibiotics
A side effect of taking antibiotics is that they can kill off some of the ‘good’ bacteria in your gut, as well as the harmful types. This can lead to diarrhoea. Probiotics help restore balance in your microbiome, reducing diarrhoea.
Several studies are being carried out to get a deeper understanding of the potential benefits of probiotics. Although areas that are being explored include skin, inflammation, blood pressure, and cholesterol, two of the most popular topics are mental health and weight loss.
Probiotics and mental health
Your gut-brain connection means your brain and gut can communicate directly with each other. And there’s some interesting research showing a link between lower levels of “good” bacteria in your gut and depression. So it makes sense that replenishing your gut with more “good bacteria” might help improve your mental health.
Specific strains of probiotics have been shown to help reduce the symptoms of anxiety and depression in people with clinical depression. Probiotics being used to improve mental health even have their own name — psychobiotics. As mentioned, it’s still early days in this area of research but it’s promising.
Probiotics and weight
There has been a lot of speculation about the link between your gut and weight. It’s been noted that people who are obese have different gut bacteria to people of normal weight. And some research has shown that specific probiotic strains can help people lose weight. But the evidence is mixed, with some animal studies showing weight gain from probiotics, not a loss.
To sum it up, it’s very early days for this area of research and you shouldn’t consider probiotics as a way to lose weight.
Probiotics have been a part of a healthy diet for hundreds of years, and are found in a variety of food including:
Because probiotics are classed as food, they're not as strictly regulated like medicines. This means that you should always double-check that:
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