Probiotics are often praised as a gut health hero. But what exactly are they, and should you be taking them for symptoms like bloating, discomfort, or an unsettled tummy?
Summary
1What are probiotics?
Live microorganisms that, when consumed in adequate amounts, may provide health benefits and help support your gut microbiome.
2Do probiotics help with bloating?
Certain probiotic strains may help reduce bloating and abdominal discomfort, although effects depend on the specific bacteria used.
3Are there any side effects of probiotics?
Some people experience temporary bloating, gas or bowel changes when starting probiotics, but these effects usually settle quickly.
Thinking about taking probiotics, or wondering if the ones you’re already using are actually doing anything for your gut health? You’re not alone. Probiotics are everywhere right now – from supplements to yoghurts and fermented drinks – all promising to support digestive health. But before adding them to your routine, it helps to understand what they actually do, how they work and whether they’re right for you.
What are probiotics?
Probiotics are live microorganisms that, when consumed in adequate amounts, can provide a health benefit.1 But not all probiotics are the same. Different products contain different strains, and the amount of research behind them can vary. When choosing a probiotic, it’s worth looking for one backed by scientific evidence that clearly lists the specific strains it contains. You’ll usually see this written as:
- Genus species ABC
The ‘ABC’ part tells you what strain the probiotic is. An example of a strain is:
- Lactobacillus acidophilus CUL-21
You’ll most often find probiotics in supplements or in certain functional foods with added live cultures. They also occur naturally in fermented foods such as yoghurt and kefir. However, not every fermented food contains live probiotic strains, so it’s always worth checking the label for named strains with proven benefits.
What are the benefits of probiotics for your gut?
Your digestive system is home to trillions of bacteria working together to keep things running smoothly. In fact, the gut microbiome weighs roughly the same as your brain, which highlights just how important these microbes are for digestive health.2,3
Depending on the strain, probiotics may help to support a range of gut health areas, including:4
- relieving bloating and gut discomfort
- easing constipation
- helping to manage diarrhoea, whether that’s from a tummy bug or from antibiotic use
Different strains are researched for different purposes, so the key is choosing the right probiotic for the issue you’re hoping to support.
Do probiotics help with bloating?
If you regularly feel bloated, you’re definitely not alone. Bloating is one of the most common digestive complaints and can leave you feeling uncomfortable or sluggish. Some gut bacteria can help to break down food and this process produces gas. When the balance of bacteria in your gut is disrupted, this process can change too, sometimes leading to excess gas and that familiar bloated feeling.5
Certain Bifidobacterium and Lactobacillus strains have shown promise for reducing bloating and abdominal discomfort in clinical trials, particularly for those experiencing symptoms linked to IBS. However, it’s important to remember that not all probiotics for gut health are for easing bloating, with some strains being studied for diarrhoea, and others being aimed at constipation or supporting other areas of gut comfort. If bloating is a long-term issue, it's worth speaking to your doctor first.
Do probiotics help with diarrhoea?
Upset stomachs can happen for lots of reasons. Antibiotics, infections, changes in digestion or water absorption in the gut can all play a role.6 If you’ve ever had a stomach bug or food poisoning, you’ll know how quickly diarrhoea can appear when the gut becomes disrupted. Some combinations of Bifidobacterium and Lactobacillus strains have been studied for their potential to support bowel regularity, and evidence suggests they may help shorten the duration of diarrhoea in certain situations.7
Antibiotics are another common trigger for diarrhoea. While they’re effective at targeting harmful bacteria, they can also affect the friendly bacteria in the gut. Probiotics containing certain Lactobacillus species may help reduce the risk of antibiotic-associated diarrhoea when taken alongside treatment.8 And remember, if you’re taking antibiotics, it’s always important to complete the full course as prescribed by your doctor.
Do probiotics help with constipation?
Constipation can happen when your digestion slows down, leaving stools harder, drier, and more difficult to pass. It’s more common than many people realise and can be triggered by things like not eating enough fibre, not drinking enough water, changes in routine, stress, travel or certain medications.9 Your gut bacteria also play a role in keeping things moving. Some probiotics, like Bifidobacterium species, have been studied for their potential in supporting regularity by maintaining a healthy balance in the gut.10
Probiotics aren’t an overnight fix, but when taken consistently alongside a balanced diet, plenty of fluids and an active lifestyle, certain strains may help support more comfortable and consistent digestion over time. If you’re experiencing digestive discomfort, it’s also important to make sure you’re meeting your daily fibre needs - adults should aim for 30g of fibre per day.11
Are there any side effects of probiotics?
When first starting a probiotic, some people may notice digestive changes as the gut adjusts, such as:
- bloating
- gas
- changes in bowel habits12
These effects are usually temporary and settle within a few days. If symptoms persist or worsen, it’s best to stop taking the product and seek advice from a healthcare professional. People with underlying health conditions or weakened immune systems should speak to a healthcare provider before taking probiotics. Speak to your GP if you’re thinking of trying them for yourself, especially if you’re sensitive to fermentable fibres or follow a low-FODMAP diet, have an underlying health condition, are pregnant or are taking medication. Certain biotics may not be suitable for everyone, and your doctor can provide advice that's tailored to you.
Probiotics FAQs
Different probiotic strains have different effects on health, they are not all the same, and not all act in the same way. They’re most commonly known for gut health, but early studies and emerging research suggest that different strains may be involved in areas like immunity, skin, vaginal health, weight management, and the gut-brain connection.13-17
If you're taking a probiotic to support your tummy, you might experience smoother digestion or fewer symptoms like wind or discomfort.18 Results aren’t instant, and how quickly you notice a difference varies from person to person as well as the species and strain of probiotic in the product. As a general guide, many probiotics are taken for at least 2–4 weeks before assessing their effect.19
Kefir is a drink made from fermenting kefir grains with milk or water, which naturally creates a diverse range of live microorganisms. However, to qualify as probiotic, it must contain live strains shown in clinical research to provide a health benefit. Make sure to check the label for specific strains, the amount provided, and whether these live cultures are guaranteed to survive through shelf life. When packed with friendly bacteria, the benefits of kefir can be broad, from supporting gut health and digestion, to helping maintain immune function and overall wellbeing.20
The final say
Feeling more clued up on probiotics for your gut? When your gut has the right balance of friendly bacteria, it can help you feel more comfortable day to day. Probiotics may be helpful when you’re suffering from gut discomfort, but they aren’t necessary for everybody. If you’re thinking about trying probiotics, start by asking yourself what you want to support, then look for products that clearly list the strains they contain and have evidence behind them. And remember, supplements are just one part of the picture. A balanced diet, enough fibre, regular movement and good sleep all play a role in supporting a healthy gut. Want to learn more? Read our guide on probiotics explained or explore probiotics and weight management.
Disclaimer – This article provides informational advice and is not a substitute for medical care. Working with experts for accuracy, we take great care to ensure the information is up-to-date and relevant. However, you should always consult your GP or healthcare professional before using supplements or alternative products, particularly if you have medical conditions or are under supervision.
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