It’s often said that probiotics and prebiotics are beneficial for gut health – but what’s the difference between them? And how do they impact our digestion? Even though probiotics and prebiotics sound similar, the two play different roles when it comes to health.
Here, we’ll explain everything you need to know about probiotics and prebiotics, including potential health benefits and how to add them to your diet.
What are probiotics and prebiotics?
Probiotics are the yeasts and live bacteria thought to help restore the natural balance of bacteria in the gut. And prebiotics are a type of fibre that these beneficial bacteria feed on. Put simply, probiotics are healthy gut bacteria, and prebiotics serve as the food for these bacteria.
Both are important for healthy maintenance of the gut microbiome, which is responsible for several key body functions.
The gut microbiome refers to the collection of bacteria and other microbes in your gut. Research has revealed that there are up to 1,000 species of bacteria in the human gut microbiome, and each plays a different role in the body. While some are linked with disease, others allow us to digest food and are essential for maintaining aspects of health such as the cardiovascular and immune systems.
We’ll take a closer look at some of these potential health benefits, and others, below.
What are the potential health benefits of probiotics and prebiotics?
Note: There has been considerable research into the health benefits of probiotics. However, it’s important to note that research into prebiotics is still developing. That being said, many of the initial findings have been positive.
May boost gut health
Having a balanced amount of probiotics and prebiotics in your diet is key for keeping your gut microbiome healthy.
A healthy microbiome is important for overall health because the good bacteria found in the digestive tract help to protect us from potentially harmful bacteria. As suggested by this study, having a wide variety of good bacteria in the gut can help to enhance immune system function, improve symptoms of depression, and tackle obesity.
Similarly, when prebiotics ferment, they produce short-chain fatty acids, which are the main food for the cells lining the colon. Keeping these cells well fed helps to create a strong gut barrier.
According to the International Scientific Association for Probiotics and Prebiotics (ISAPP), short-chain fatty acids are essential for gut health because they help to keep out harmful bacteria and viruses. In turn, this can also reduce inflammation, which is linked with a higher risk of disease, including cancer.
May help to ease symptoms of gastrointestinal conditions
Probiotics have become widely recognised for their ability to treat gastrointestinal issues like diarrhea.
This scientific review found that certain strains of probiotics cleared up diarrhea-related illnesses faster. Another study noted that probiotics reduced the risk of travellers’ diarrhea. That being said, it’s important to note that effectiveness will vary depending on the type and amount of probiotic taken.
On the other hand, if you suffer with constipation, prebiotics may offer some relief. This study concluded that inulin (a type of prebiotic) may benefit people who have constipation-related irritable bowel syndrome (IBS). Another study confirmed these findings. Evidence suggests this could be due to the fact that prebiotics may help to improve the frequency and consistency of stools, as well as the time taken for food to move through the digestive tract.
That said, bloating and gas are common side effects of prebiotics, so it’s worth introducing them to your diet slowly or moderating your intake if you’re prone to these kinds of symptoms.
May improve mental health and reduce the risk of conditions like depression
There’s an increasing amount of evidence linking gut health with mood and mental health.
In this scientific review, supplementing with probiotics for one to two months improved symptoms of anxiety, depression, autism, memory, and obsessive-compulsive disorder (OCD).
Another study found that taking probiotic supplements for eight weeks improved symptoms of depression and reduced levels of C-reactive protein (a marker of inflammation), compared to people who didn’t take a probiotic.
May boost heart health
Researchers have found that our guts are tied to the health of other body parts, including our hearts. The relationship between the digestive and cardiovascular systems is known as the gut-heart axis.
Studies have linked bacterial imbalances in the gut with higher levels of inflammation and a weaker immune system – both of which are risk factors for developing heart disease. So, if the balance of your gut microbiome affects the risk of heart disease, it stands to reason that probiotics and prebiotics may benefit heart health.
Research has found that probiotics may help to decrease inflammation and oxidative stress, which are drivers of heart disease; while another study linked prebiotic intake with reduced levels of inflammatory markers, such as high-sensitivity C-reactive protein (hs-CRP). High levels of hs-CRP in the blood has been linked to an increased risk of heart attack.
Other research also suggests that both probiotics and prebiotics can support healthy improvements in cholesterol, blood pressure, and triglyceride levels – all of which are important for heart health. Lastly, it’s worth noting that many prebiotic food sources, such as fruits, vegetables, and legumes, are consistently linked with a reduced risk of heart disease.
May support healthy weight loss
Some research has linked probiotics and prebiotics with healthy weight loss – and there are a variety of reasons why.
Firstly, some probiotics have been found to prevent the absorption of dietary fat in the intestine. The fat is then excreted instead of being stored in the body.
Similarly, some people report experiencing fewer cravings and feeling fuller after introducing prebiotics to their diet. This can be effective for preventing overeating, encouraging portion control, and therefore, achieving healthy weight loss.
In this study, oligofructose, a type of prebiotic found naturally in foods like onions, leeks, garlic, and oats, can suppress the hunger hormone ghrelin in overweight adults.
May improve mineral absorption
Getting the right amount of vitamins and minerals is key for health, and there’s evidence to suggest that prebiotics may help to improve the body’s absorption of these nutrients.
For example, some studies suggest that prebiotics may help to improve the absorption of minerals like calcium, which, among other things, is essential for maintaining healthy bones and teeth.
May help to regulate blood sugar levels
For people with diabetes, regulating blood sugar levels is important for managing symptoms. Research suggests that prebiotics may be effective at improving blood sugar control.
This scientific review found that taking prebiotics lowered fasting blood sugar levels. However, further research is needed to confirm these findings.
For example, this study reported that prebiotics caused little difference to fasting glucose levels in people with type 2 diabetes – though it’s unclear whether they need to be taken for a longer period to affect blood sugar levels.
May boost immune system function
Research suggests that a healthy gut microbiome supports the body’s natural defenses and may improve immunity. Since a healthy balance of probiotics and prebiotics is needed for gut health, it’s possible that they play a considerable role in this.
Plus, increased immunity is linked with lower levels of inflammation; and studies have found that prebiotics can be effective at reducing inflammation, largely due to their role in strengthening the gut barrier.
How can I add probiotics and prebiotics to my diet?
Now that you know some of the potential health benefits of probiotics and prebiotics, you might be wondering how you can add them to your diet.
Below, we’ll explore some of the best sources of probiotics and prebiotics.
Best sources of probiotics
There are many probiotic foods that naturally contain good bacteria. One of the best sources is high-quality, plain yoghurt that contains live cultures.
Fermented foods, such as kimchi, miso, sauerkraut, and kefir, are another fantastic option. This is because gut-friendly bacteria thrive off of the naturally occurring fibre and sugar found in fermented foods.
Different types of fermented foods contain varying strains of probiotics (each with their own benefits), so eating a variety of fermented foods can be beneficial.
To find out more, you might be interested in our articles; 8 fermented foods for gut health and How to make your own fermented foods at home.
Best sources of prebiotics
Because prebiotics are types of fibre found in fruits, vegetables, and legumes, the good news is that they occur naturally in many foods.
Some of the best sources of prebiotics include beans, peas, garlic, barley, leeks, bananas, oats, asparagus, apples, potatoes, and Jerusalem artichoke.
To find out more, check out our list of 13 prebiotic foods to add to your diet. And, to get started in the kitchen, you might like to try one of these plant-based prebiotic recipes from One Green Planet.
Should I take a probiotic or prebiotic supplement?
Alongside the various food sources, probiotics and prebiotics are also available in supplement form.
However, it’s important to always speak to your GP before adding any new supplements to your diet as they won’t be suitable for everyone.
Final thoughts…
Probiotics and prebiotics remain a hot topic when it comes to gut health. And, as this article has hopefully shown, our digestive health has the potential to impact our overall health. So, taking the time to understand the role of probiotics and prebiotics can be a useful step to take.
For further reading, head over to the diet and nutrition and general health sections of our website. Here, you’ll find information on everything from gut health to simple food swaps for a healthier lifestyle.
What’s your experience of probiotics and prebiotics? Did you learn anything new from our article? We’d be interested to hear from you in the comments below.
