Probiotics vs. Prebiotics—Everything You Need To Know

Probiotics vs. Prebiotics—Everything You Need To Know

Gut health is like a buzzword these days. Wherever you look, you’ll find someone talking about it. Between the best time to take them, supplements, foods, benefits, and side effects, you might get a headache trying to understand it all. Plus, the whole topic of probiotics vs. prebiotics can confuse things even more.

Is one better than the other? Should you choose a symbiotic—a supplement containing both—to get the best of both worlds?

Welcome to our gut health series. Follow along to dive into this topic and make it a little less complicated.

Probiotics vs. prebiotics. What are they?

The two may sound alike, but there’s more than one letter that differentiates them.

  • Probiotics are, in simple terms, the good bacteria. You can find these live microorganisms in certain foods and supplements, and they come with many benefits.
  • Prebiotics are food for the good bacteria. They come from certain carbs, usually fiber, and humans don’t digest them, but good bacteria do.

In other words, despite all talk about “probiotics vs. prebiotics,” the two do not compete. Instead, they complement each other.

Probiotics benefits

Probiotics are great for gut health, which is good for your entire body, from the digestive to the immune system and beyond. Here are their major benefits.

  1. Probiotics help treat and prevent diarrhea. By balancing the bacteria in your gut, probiotics help treat diarrhea. Studies have also shown you can use it to prevent things like traveler’s diarrhea. The effect may vary on the severity of your symptoms, their cause, and the type of probiotics. While in some cases, like food poisoning or irritable bowel syndrome, it may feel like they help little, they may help reduce the duration of your symptoms.
  2. They may improve your mental health. Several studies link gut health and mental health. Supplementing with probiotics seems to reduce symptoms of anxiety, depression, and obsessive-compulsive disorder (OCD).
  3. They may boost your immune system. A healthy gut means your body processes food more effectively, helping you easily absorb nutrients from food. That means you get more vitamins, minerals, and other nutrients from your diet, which will positively impact your immune system.
  4. Probiotics may help you lose weight. When your GI tract is healthy and happy and absorbs all the nutrients, your entire body functions better. That means it may be easier for you to listen to your hunger signals and make better food choices.

Prebiotics benefits

Prebiotics are food for good bacteria, which means they help boost the benefits of the probiotics. Because they come mainly from fiber, they can also:

  • Help reduce appetite and cravings
  • Improve gut conditions such as diarrhea and constipation
  • Help boost the immune system
  • Improve blood sugar levels

Do probiotics and prebiotics have side effects?

The dose makes the poison, whether it’s a glass of wine versus an entire bottle or a handful of chips versus a family-sized bag. You know the difference.

If you suddenly introduce foods high in prebiotics and probiotics into your diet, your body may need some time to adjust. The same is true for supplements.

Let’s look at yogurt (vegan or not), a food high in probiotics. If you’re not a regular yogurt eater and decide to have a serving (or more) of yogurt, you may find yourself running to the bathroom.

This doesn't mean yogurt is bad for you if you’re eating the dairy version while being lactose intolerant. It means you ate a little too much, and your body needs time to adjust.

Other side effects of foods and supplements with probiotics include:

  • Gas
  • Bloating
  • Mild cramps

Finally, always check the label if you are vegan and want to take a supplement. Many probiotics contain non-vegan ingredients, such as dairy. The good news is there are plenty of options, so finding alternatives will be easy.

Do we need probiotics and prebiotics?

We don’t need probiotics or prebiotics like we need vitamins and minerals. But gut health is important for your overall health.

Plus, prebiotics are primarily fiber. Depending on your diet, you may already consume sufficient prebiotics to keep those good gut bacteria happy.

But there may be an issue if you’re one of the 97% of Americans who don’t consume enough fiber in their diet. Plus, some conditions like ulcerative colitis or Chron’s disease may affect your diet and how your body processes foods.

In other words, it all depends on your diet and other circumstances in your life. If you:

  • Are traveling while also eating junk foods or trying foods you’ve never eaten before
  • Take medication that affects gut health, such as antibiotics
  • Have certain conditions that impact gut health

You may consider taking a supplement or consuming more foods high in pro- and prebiotics.

A word on probiotics and antibiotics

Love them or hate them, sometimes you’ll need to take antibiotics. And many people recommend taking probiotics alongside antibiotics.

That’s because while they fight infections and bad bacteria, they also tend to kill the good bacteria in your gut as well. It’s not a coincidence that diarrhea and other digestive issues are some of the most common side effects.

Taking a probiotic helps keep your good bacteria at a healthy level, repairing the damage done by the antibiotics. It may also help prevent yeast infection, another common side effect.

Remember to take the supplements as instructed because taking them at the wrong time may interfere with the effect of the antibiotic.

What if you don’t supplement? Does your gut rebalance itself on its own?

Yes, it might, especially if you eat foods high in prebiotics and probiotics. Even some studies suggest gut microbiome repair is faster in those who don’t supplement.

In the end, it is a question of personal choice. Do you want to take your chances with things like diarrhea and candida? Then you can try to wait it out.

Foods high in probiotics and prebiotics

Getting nutrients from food is always the best option. And that’s true for probiotics and prebiotics too. So, what foods should you include in your diet to keep your gut microbiome healthy and happy? Here’s a quick cheat sheet.

Foods that contain prebiotics include:

  • Bananas
  • Oats
  • Legumes
  • Beans
  • Onions
  • Garlic
  • Peas
  • Berries

Foods high inprobiotics are usually fermented ones and include:

  • Kombucha
  • Kefir and yogurt (dairy and vegan)
  • Kimchi
  • Sauerkraut
  • Unpasteurized pickles
  • Tempeh
  • Miso

When is the best time of day to take supplements with probiotics?

There’s no universal answer, as it varies based on different factors.

Follow your doctor's instructions if you’re using the supplements with antibiotics or any other medication. Alternatively, check the instructions your supplement comes with. It will give you a hint on what medications it can interact with and when you can take them.

If you're not taking other medication and the supplement you take comes with no timing restrictions, it’s mostly up to you.

Some say meal composition may help. Taking a probiotic with a meal consisting of foods high in prebiotics could maximize its absorption.

Can you take them on an empty stomach? Again, it depends both on you and how your body reacts, but also on the type of probiotics you’re taking.

There are some supplements you shouldn’t take on an empty stomach, while others will be fine. Similarly, some people don’t react well to any supplements before they have something to eat. In that case, taking your probiotics with food is the best option.

Probiotics, prebiotics, and weight loss

We briefly mentioned probiotics and prebiotics might help with weight loss. Let’s take a closer look at what research tells us. Do probiotics really help you lose weight? And if so, how and why does that happen?

The answer goes back to gut health. The good bacteria living in your GI tract improve the absorption of vitamins and minerals and help break down fiber that your body can’t otherwise digest.

Several studies conducted on both animals and humans have shown that those of moderate weight have different gut bacteria composition than those who are overweight.

Plus, we know foods with a lot of fiber and, implicitly, prebiotics make you feel full faster and can reduce cravings. All that is a real asset if you’re trying to lose weight.

And if high appetite and cravings are an issue for you, probiotics may also help. Some studies suggest probiotics help the body make more appetite-suppressing hormones, which will also help you burn calories.

There’s another fun fact about probiotics. A 4-week study was conducted on people who were eating about 1,000 calories more than their daily needs. On top of that, they were also given a daily probiotic called VSL#3. The control group took a placebo.

Those in the probiotic group gained significantly less fat during those 4 weeks. There was, however, no improvement in insulin sensitivity.

No, this doesn’t mean you can overeat all you want as long as you take a probiotic. Overeating can still have a negative impact on your health and increase your risk of diabetes, heart disease, and other complications. But it proves probiotics help us absorb food better and manage our weight more easily.

Probiotics and intermittent fasting

Should you take a probiotic while intermittent fasting? You can. Especially if you pair it with prebiotics, it could help reduce your cravings.

Be mindful of the time of day when you take it, though. While taking it in your fasting window might be tempting, not everyone reacts well to taking supplements on an empty stomach.

And, of course, don’t forget to read the label or check with a healthcare provider. Some probiotics need to be taken with food.

Key takeaways

A healthy gut microbiome is crucial for your overall health. Probiotics are good bacteria that help your GI tract be happy. Prebiotics are food for probiotics.

You can get probiotics from fermented foods and prebiotics from high-fiber foods, and some starch. They work best together, but one might be enough if you choose to supplement. It all depends on your goals.

Probiotics and prebiotics may boost the immune system, help you lose weight, treat and prevent diarrhea and constipation, and may even improve your mental health.

As always, getting nutrients from food is the best option. But sometimes supplements are necessary. If that’s your case, we may be able to help you, so check out our shop to learn more. 

Health/Medical Disclaimer

This blog post does not provide health or medical advice. This blog post is for informational and educational purposes only and is not a substitute for professional health or medical advice. Before taking any actions based upon such information, we encourage you to consult with the appropriate medical and healthcare professionals. We do not provide any kind of health or medical advice. The use or reliance of any information contained on this blog is solely at your own risk. 


26th Jul 2021 Written by Laura Vegh. Edited by Brandee Nichols, retired Registered Nurse.

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