Probiotics are beneficial bacteria, and prebiotics are food for these bacteria. Eating foods or supplements containing both can help balance your gut.
Probiotics and prebiotics are both hot topics in nutrition these days. Yet, even though they sound similar, the two play different roles in health.
We’ll explain what you need to know about the two.
The difference between probiotics and prebiotics
Both prebiotics and probiotics are important for maintaining healthy gut bacteria, collectively referred to as the gut flora or gut microbiota. However, they have different roles.
Probiotics are live bacteria in certain foods or supplements that can provide numerous health benefits to the gut when consumed. Examples of foods that contain probiotics include fermented foods like yogurt and sauerkraut.
Meanwhile, prebiotics are high fiber foods that serve as “food” for probiotics, allowing them to function properly and effectively. Examples of prebiotic foods are fruits, vegetables, and whole grains.
Benefits of probiotics and prebiotics
The good bacteria in your digestive tract help protect you from harmful bacteria and fungi. A 2022 research article on gut bacteria and health confirms that a wide variety of this good type of bacteria can aid in immune system functions and help address obesity, among other benefits.
Another 2019 literature review suggests that they can also help improve symptoms of depression and anxiety.
Additionally, some gut bacteria form vitamin K and short-chain fatty acids, which are the main nutrient source of the cells lining the colon.
They promote a strong gut barrier that helps keep out harmful substances, viruses, and bacteria. This also helps reduce inflammation and may reduce the risk of cancer.
Probiotics can help support the composition of bacteria in your gut and may even help increase the amount of beneficial bacteria and decrease the number of harmful ones. Meanwhile, prebiotics can give the probiotics the fuel they need to work.
Is it better to take a prebiotic or probiotic?
Probiotics and prebiotics work best in tandem. For probiotics to work best, you need to eat prebiotic foods, too. This can lead to improved digestive function and overall health.
How does food affect the gut microbiota?
The food you eat plays an important role in the balance of good and bad gut bacteria.
For example, a high carbohydrate and sugar diet negatively influences gut bacteria and may contribute to insulin resistance and other conditions.
Once you regularly feed the wrong bacteria, they can grow faster and colonize more easily without as many helpful bacteria to prevent them from doing so.
Harmful bacteria and less healthy gut flora have also been associated with a higher body mass index (BMI). Additionally, foods treated with pesticides may have negative effects on gut bacteria, although more research is needed to confirm this.
However, eating probiotics and prebiotics can help offset these negative effects.
Research has also shown that antibiotics can permanently change certain types of bacteria, especially when taken during childhood and adolescence.
In particular, it can lead to antimicrobial resistance, which is when microorganisms such as bacteria change in a way that makes them unresponsive to medicines. This can raise the chance of diseases spreading and cause more severe sickness and even death.
For this reason, researchers are looking into how probiotics and prebiotics might be able to offset the effect of antibiotics on the gut.
Which foods are prebiotic?
Before you go out and buy expensive prebiotic supplements, remember that many foods naturally contain them.
That’s because prebiotics are types of fiber found in vegetables, fruits, and legumes.
Foods that are high in prebiotic fiber include:
- legumes, beans, and peas
- oats
- bananas
- berries
- Jerusalem artichokes (not the same as regular artichokes)
- asparagus
- dandelion greens
- garlic
- leeks
- onions
One thing your good gut bacteria do with prebiotic fiber is turn it into a short-chain fatty acid called butyrate.
Research suggests that butyrate production in the colon cannot be maintained without adequate intake of prebiotic fiber.
Which foods are probiotic?
Many probiotic foods naturally contain helpful bacteria, such as yogurt.
A high quality, plain yogurt with live cultures can be a fantastic addition to your diet if you want to add beneficial bacteria.
Fermented foods are another great option, as they contain beneficial bacteria that thrive on the naturally occurring sugar or fiber in the food.
Examples of fermented foods include:
- sauerkraut
- kimchi
- kombucha tea
- kefir (dairy and nondairy)
- some types of pickles (unpasteurized)
- other pickled vegetables (unpasteurized)
If you’re going to eat fermented foods for their probiotic benefits, make sure they’re not pasteurized, as this process kills the bacteria.
Some of those foods can also be considered synbiotics because they contain both beneficial bacteria and a prebiotic source of fiber for the bacteria to feed on.
Some examples of synbiotic foods are cheese, kefir, and sauerkraut.
Should I take probiotic supplements?
Probiotic supplements are pills, powders, or liquids that contain live beneficial bacteria or yeast. They’re very popular and easy to find, but not all are worth your money.
The right strains of probiotics can be incredibly beneficial for some people. However, the type of strain, product formula, quality of the product, and storage can affect how they are absorbed and their beneficial effects on health.
Not all supplements have the same types of bacteria or the same concentrations. Many products on the market make claims without proof of efficacy.
Also, they usually don’t contain prebiotic sources for the bacteria to eat, which can hinder their effectiveness.
Moreover, many probiotics don’t tolerate stomach acid well, which can reduce their effectiveness. However, this, too, depends on the strain or the combination of strains. If you’re looking for a probiotic supplement, ask your doctor which type is best for you.
Who should not take prebiotics or probiotics?
Generally, it’s accepted that some individuals, such as people with small intestinal bacterial overgrowth (SIBO) or irritable bowel syndrome (IBS), shouldn’t consume probiotics or prebiotics, as these may worsen their symptoms.
However, a new 2023 literature review suggests that some strains of probiotics might actually help improve IBS symptoms. For this reason, if you have IBS, speak with your doctor first to determine if probiotics may help you.
As with all supplements, you may want to consult a healthcare professional knowledgeable about probiotics.
The bottom line
Keeping your gut bacteria balanced is important for many aspects of health.
To do this, eat plenty of both prebiotic and probiotic foods, as they will help promote the most ideal balance between good and bad gut bacteria.
Talk with your healthcare professional to ensure you’re eating the right amounts of each. It’s possible to go overboard or experience side effects.
To see if you could benefit from a supplement, check out the World Gastroenterology Organization Global Guidelines list of evidence-based conditions that probiotics could potentially help. It also includes recommendations.
Please read the labels on any supplements carefully and discuss any questions or recommendations with your healthcare professional.