Probiotics are growing in popularity – people are taking them to relieve a wide range of symptoms. But how can you tell if they’re working?
The signs of success will depend on many factors, including the symptoms you’re tackling. You may notice an easing up of gut symptoms, better sleep and improvements in your skin.
In this article, we’ll describe what to look out for and how long it may take probiotics to work. We’ll also answer some common questions about probiotics.
First, let’s explore what probiotics are.
What are probiotics?
Probiotics are live microorganisms, such as bacteria and yeasts, that benefit health when consumed in the right amounts.
Scientists have considered a wide range of uses for probiotics. So far, researchers have investigated whether they might help treat:
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eczema
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acute infectious diarrhoea in children
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diarrhoea associated with antibiotics or travelling
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gut disorders, like inflammatory bowel disease (IBD), irritable bowel syndrome (IBS) and acid reflux (GERD)
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elevated cholesterol levels
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vaginal infections
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upper respiratory tract infections
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H. pylori infection
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mental health conditions
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sleep disorders
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neurological conditions, including Parkinson’s and multiple sclerosis
Probiotic products come in many forms – from pills and powders to drinks and gummies. The strains of bacteria in these probiotics also vary.
Some of the most common ‘good’ bacteria in probiotic products are species of Lactobacillus and Bifidobacterium, such as:
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L. casei
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L. plantarum
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B. animalis
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B. longum
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B. breve
Scientists are still investigating precisely how probiotics might benefit health. But one of the most likely ways is by supporting your gut microbiome – the trillions of microbes that live in your gut.
We know that the gut microbiome plays an important role in maintaining good health. And an unbalanced gut microbiome, which experts call dysbiosis, is linked with health conditions.
Probiotics may help restore balance and support this complex community of microbes.
How do you know if your probiotics are working?
Signs that your probiotics are working can depend on many factors, including:
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the symptoms you’re experiencing
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their severity
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their underlying causes
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which probiotic strains you’re taking
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the health of your gut microbiome
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your overall diet and lifestyle, including how active you are, whether you smoke, how stressed you're feeling and which medications you're taking
With all of these influences in mind, there are still some general signs that probiotics are working, and we’ll dive into those next.
Improvements in gut symptoms
A common reason for taking probiotics is to tackle gastrointestinal symptoms, like indigestion, nausea, bloating, excess wind, diarrhoea and constipation.
Even if this wasn’t your primary reason for taking probiotics, you might still notice minor improvements.
There’s also some evidence that some probiotics might help relieve symptoms of IBS, including bloating.
Certain strains, namely Saccharomyces cerevisiae and certain types of Bifidobacterium and Lactobacillus bacteria, might help reduce stomach pain and cramps for people with IBS.
If you’re experiencing this symptom, and it eases up while you’re taking probiotics, this could be a sign that your probiotic product is working.
However, it’s worth noting that for some people, probiotics may temporarily increase bloating and wind. We’ll cover this in more detail later on.
Better sleep
Trouble sleeping is another common reason for taking probiotics. Again, even if this isn’t your primary concern, you may still notice benefits.
Some small studies suggest that specific probiotic strains might improve your sleep quality. And increased gut microbiome diversity is linked to longer sleep times.
It may be surprising that consuming live bacteria could influence your sleep. However, your gut and brain are tightly linked through a series of connections called the gut-brain axis.
Both areas of the body communicate, and they influence each other. After all, your brain needs to know when your gut is empty.
You might also notice the gut-brain axis at work if you feel ‘butterflies’ in your stomach before an exam or job interview.
Better mood
Staying with the gut-brain axis: there’s evidence that a happy gut microbiome might improve your psychological mood.
A systematic review and meta-analysis, for instance, concluded that ‘Probiotics were associated with a significant reduction in depression.’
And a similar review determined that ‘Probiotics yielded small but significant effects for depression and anxiety.’
So, if you have an extra spring in your step, perhaps it’s the probiotics.
Improvements in vaginal infections
As we mentioned above, ‘dysbiosis’ refers to an imbalance in the population of microorganisms living in your gut microbiome.
An imbalance can also occur in the vaginal microbiome, and this condition is called bacterial vaginosis.
Researchers are still investigating whether probiotics might help. Some have concluded that certain people who take probiotics might experience fewer or less severe vaginal infections.
And the authors of one review determined that ‘Probiotics may play a positive role in the treatment of [bacterial vaginosis].’
Scientists suspect that oral probiotics might help fend off these infections through the so-called gut-vagina axis.
Whether taking probiotics orally can influence vaginal health is the subject of ongoing research. One theory is that improving the gut microbiome may help regulate the vaginal microbiome.
It's also possible that compounds produced by the gut microbiome pass into the bloodstream and have effects elsewhere, including the vagina.
Skin changes
How might probiotics influence your skin? You’ve guessed it, the skin-gut axis.
There hasn’t been a great deal of research into the effects of oral probiotics on skin health. But some evidence suggests that certain people might notice benefits, such as reduced acne symptoms and skin inflammation.
Research also points to a lower risk of eczema in children who take probiotics, and also when the mums have taken probiotics during pregnancy.
In addition, there’s evidence that probiotics can help reduce the severity of eczema in adults.
Side effects
Some people may experience an increase in some gut issues, like excess wind and bloating, when they start taking probiotics. As the population of your gut microbiome changes, so does the amount of gas it produces.
If this happens, the effects usually subside as your body gets used to the changes.
But if they’re particularly uncomfortable, stop taking the probiotics and speak with your doctor or pharmacist.
How long does it take probiotics to work?
Because we take probiotics for different reasons, and everyone’s gut microbiome and overall health are unique, there’s no hard-and-fast measure of how long probiotics take to work.
Timing can also depend on the product you’re using, the strains it contains, and the dosage.
However, in general, around 4–12 weeks is a good, rough estimate.
Summary
Probiotics are live bacteria that benefit health when consumed in the right amounts.
The signs that they’re working vary between people. You might notice improved gut symptoms, better sleep and increased mood.
Some people might also have fewer vaginal infections and improved skin health.
How quickly probiotics start working depends on a number of factors, including your symptoms and the type of probiotics you’re taking.
To learn more about gut health, visit Symprove’s Gut Hub.
Sources
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Effects of probiotic NVP-1704 on mental health and sleep in healthy adults: An 8-week randomised, double-blind, placebo-controlled trial. Nutrients. (2021). Link.
Effects of probiotics on cognitive reactivity, mood, and sleep quality. Frontiers in Psychiatry. (2019). Link.
Effect of probiotics on depression: A systematic review and meta-analysis of randomized controlled trials. Nutrients. (2016). Link.
Efficacy of prebiotics, probiotics, and synbiotics in irritable bowel syndrome and chronic idiopathic constipation: Systematic review and meta-analysis. American Journal of Gastroenterology. (2014). Link.
Gut microbiome diversity is associated with sleep physiology in humans. PLOS One. (2019). Link.
Gut microbiome health and dysbiosis: A clinical primer. Pharmacotherapy. (2022). Link.
Healthy vaginal microbiota and influence of probiotics across the female life span. Frontiers in Microbiology. (2022). Link.
Oral and topical probiotics and postbiotics in skincare and dermatological therapy: A concise review. Microorganisms. (2023). Link.
Prebiotics and probiotics for depression and anxiety: A systematic review and meta-analysis of controlled clinical trials. Neuroscience and Biobehavioral Review. (2019). Link.
Probiotics and functional abdominal bloating. Journal of Clinical Gastroenterology. (2004). Link.
Probiotics are a good choice for the treatment of bacterial vaginosis: A meta-analysis of randomized controlled trial. Reproductive Health. (2022). Link.
Systematic review: Probiotics in the management of lower gastrointestinal symptoms – an updated evidence‐based international consensus. Alimentary Pharmacology and Therapeutics. (2018). Link.
The efficacy of probiotics supplementation for the treatment of atopic dermatitis in adults: A systematic review and meta-analysis. Journal of Dermatological Treatment. (2022). Link.
The human gut microbiome in health and disease. Metagenomics. (2018). Link.
The prevention effect of probiotics against eczema in children: An update systematic review and meta-analysis. Journal of Dermatological Treatment. (2022). Link.
Warding off recurrent yeast and bacterial vaginal infections: Lactoferrin and Lactobacilli. Microorganisms. (2020). Link.
