Gut Health 101: Probiotics and Prebiotics

Probiotics are popular right now, especially for people dealing with bloating, irregularity, or issues like irritable bowel syndrome (IBS) or antibiotics-related stomach troubles. These “good bacteria” are in everything from yogurt and kombucha to pills you can buy at the store. But do they really work?

The truth is, probiotics can help your digestive system in important ways, but they aren’t a fix-all solution. How well they work depends on the type of probiotic, your own gut health, and what’s causing your symptoms. And you shouldn’t forget about prebiotics, which help probiotics thrive.

To help you in deciding if probiotics and prebiotics are right for you, below is information on how probiotics work, what prebiotics do, what probiotics can’t fix, and how to know if these tools are helping you.

How probiotics and prebiotics help your gut

Your gut microbiome is home to tiny living things like bacteria that work hard to break down food, absorb nutrients, support your immune system, and even impact your mood. But when your gut gets out of balance—due to illness, stress, poor diet, or antibiotics—digestive problems often follow.

That’s where probiotics and prebiotics come in.

Probiotics are live microorganisms that can help restore balance in your gut when taken in the right amounts. You can find them in fermented foods like yogurt, kefir, and sauerkraut, or in supplement form. Probiotics help:

• Crowd out harmful bacteria by competing for space.
• Strengthen your gut lining to reduce inflammation.
• Help you digest certain foods like fiber and lactose.
• Restore good bacteria after illnesses or antibiotic use.

On the other hand, prebiotics serve as food for probiotics and other beneficial bacteria in your gut. Prebiotics come from certain types of fiber that the body can’t digest, commonly found in foods like bananas, onions, garlic, asparagus, and whole grains. Supporting your gut microbiome with prebiotics can lead to better probiotic effectiveness.

A 2022 study in Cureus even found that probiotics, supported by prebiotic intake, may ease symptoms of IBS like bloating and gas by improving gut health and calming inflammation. However, it is important to remember, the success of probiotics and prebiotics depends on choosing the right ones for your unique needs.

What probiotics and prebiotics can’t do

While probiotics and prebiotics can be helpful, they still have limitations. Here's what they can’t do:

• Probiotics can’t cure chronic gastrointestinal (GI) conditions like Crohn’s disease or celiac disease. These require medical treatment, though probiotics or prebiotics may ease mild symptoms in some cases.
  
  
• Not all strains are created equal. If you’re using the wrong type of probiotic strain, your specific symptoms may not improve. Similarly, not all foods labeled as “prebiotic” provide meaningful benefits for everyone. You should talk with your doctor or advanced practice provider* (APP) to understand your unique gut needs and what strain would work best for you. 
  
  
• Storage and usage matter. Probiotics are alive, so heat, humidity or inconsistent use can make them less effective. Prebiotics also require regular dietary intake to maintain their benefits.
  
  
• Side effects may occur. Some people experience bloating or gas from probiotics, especially when first starting, or from prebiotic-rich foods if consumed in excess.

How to tell if your probiotics and prebiotics are working

Taking a probiotic or combination of probiotics and prebiotics won’t provide instant results, but if they’re helping, you might notice changes within a few weeks. Here’s what to look for:

• Improved regularity with bowel movements.
• Less bloating or gas.
• Softer, more consistent stools.
• Reduced bathroom emergencies.
• Improved digestion of tricky foods like dairy or high-fiber items.

If nothing changes after a few weeks or your symptoms get worse, it could mean the probiotics/prebiotics you’re trying aren’t the right fit for your specific needs or microbiome.

When to see your doctor or APP

Even though probiotics and prebiotics are available over the counter and in everyday foods, they’re not risk-free for everyone. If you’ve had persistent digestive issues, it’s smart to check in with doctor or APP before starting probiotics or significantly increasing your intake of prebiotics. You should make an appointment to see your doctor or APP immediately if you have any of the following symptoms:

• Digestive problems that last longer than a few weeks.
• Pre-existing conditions like IBS or food intolerances.
• Unexplained weight loss, fatigue or blood in your stool.

Together, probiotics and prebiotics are useful but not a miracle fix. Choosing the right type, pairing them effectively, and being consistent are key to seeing results. Your doctor or APP are available to help you build a gut health plan tailored to you. Together, you can take the guesswork out of probiotics and prebiotics while supporting your overall well-being.

* An advanced practice provider includes a nurse practitioner or physician assistant.