(Woodpath is an education site focused exclusively on gut health. Our articles are researched by clinical nutritionists and contain citations at the end of the page.)

Probiotics and gut health go hand in hand. Studies link probiotics to potentially improved digestion, a stronger immune system, and increased mental clarity.

But are probiotics indeed a panacea? Is there such a thing as "too much" when it comes to probiotics? Could probiotics be bad for your health?

While there are many health benefits related to probiotics, there can be some side effects as well, especially for someone who has a severe health condition, a compromised immune system or has had surgery.

Who Should Take Probiotics?

Whether or not you take probiotic supplements, your body already produces probiotics in your digestive system through the foods you eat. This is why a balanced diet that includes prebiotic and probiotic foods is integral to overall health.

But the reality is that not everyone eats enough whole, high-fiber, probiotic-rich foods consistently to maintain balanced gut bacteria.

Nutrient-poor snacks, processed meat products, and sugary treats are a go-to convenience for many people, thus making it a challenge to attain, maintain, and restore a strong, healthy gut.

Indeed, taking probiotic supplements might be useful for many people who are trying to address particular health problems, but they may not be good for everyone. Probiotics also need to be chosen appropriately by the strain (not the species) for a particular, indicated cause.

Older adults and those who have a weakened immune system caused by illness or medication, leaky gut, or other critical condition run the risk of severe infection and can have severe allergic reactions from too much probiotic bacteria. (Fijan 2014)

A good rule of thumb: Consult your physician or pharmacist before taking any new supplements.

Which Probiotics Should I Take?

Not all probiotics are created equal —  not all strains are the same. Look for reputable companies that use high-quality strains that have been vetted and verified in science-based clinical studies.

It's also important to understand the different strains of probiotics so you can make an educated decision about what might work for you.

The most common probiotic strains are species of Lactobacillus, Bifidobacterium, and Saccharomyces, all of which have demonstrated health-promoting benefits in scientific studies.

How Many Probiotics Should be Consumed?

According to Consumer Labs — a third-party organization that tests health and nutrition products — a probiotic supplement should have at least one billion CFUs (colony forming units) for each daily adult dose. 

These CFUs indicate the number of live bacteria in each dose and most commonly range between one billion and 10 billion.

Again, the particular strains of probiotics you take, along with the amount of probiotics you ingest, will influence how your body responds. A combination of probiotic strains might be effective for some, while a single-strain product can also be sufficient for others.

This process of discovery — and perhaps elimination — will require some experimenting and a fair amount of patience, so don't get discouraged.

Health Benefits of Probiotics

Consuming probiotics either through supplements or food may help promote improved gut health, which can then potentially promote many health benefits such as:

  • Strong immune system
  • Ease of digestion
  • Mental sharpness
  • Reduced fatigue
  • Decreased bloating
  • Diminished joint pain
  • Treatment of diarrhea or constipation

Side Effects of Probiotics

While many people do not experience side effects from taking probiotics, some potential side effects might include the following:

  • Intestinal gas
  • Bloating
  • Flatulence
  • Diarrhea

How to Avoid Probiotic Side Effects

It's not uncommon for people to experience a little gas and bloating during the first few days of taking a new probiotic supplement. As your gut adapts and balances itself, these symptoms will subside. 

To circumvent the most common side effects and spare yourself some uncomfortable situations, follow these helpful tips:

Lower your dosage

As with so many other things in life, moderation is key when it comes to probiotics. You might be eager to introduce your digestive tract to higher doses of probiotics, but sometimes less is more.

Because the range of CFUs can vary so greatly, consider adjusting your intake to a smaller dose of probiotics (such as half) and allow at least a week to see if your digestive system recalibrates.

Change the probiotic strain

Different bacteria help with different issues, so make sure you take the right combination for your particular needs. For example, probiotics such as Saccharomyces boulardii have been shown to curtail the duration of diarrhea and other gastrointestinal issues, but efficacy is not necessarily observed for Lactobacillus acidophilus. (Ritchie 2012)

Take on an empty stomach

Because probiotics can produce gas when combined with certain foods, you can try to take your probiotic at least 30 minutes before you eat. If that doesn't work, you can also try taking it at bedtime after you're done eating for the day.

Take activated charcoal

This can help if you are experiencing excess gas - either in the form of bloating or flatulence. Take this 2 hours away from food or medications.

If negative symptoms persist or you still have questions, be sure to contact a healthcare professional to ensure you get proper medical advice and treatment.

Where are Probiotics Found?

Probiotics naturally occur in the body's digestive system, deriving from the foods we eat. Probiotics are found in fermented foods such as dairy products including milk, yogurt, and cheese.

If you suffer from lactose intolerance or adhere to a dairy-free diet, there are plenty of other naturally occurring probiotic-rich foods. These include pickles, sauerkraut, kimchi, miso soup, tempeh (fermented soybeans), sourdough bread, kefir, and kombucha tea drinks.

Of course, you can also find probiotic supplements in your local supermarket, health food store, and pharmacy.

How do Probiotics Work?

It might seem a bit contrary to what we think about bacteria, but not all bacteria are bad bacteria. Just one look at the many antibacterial products on store shelves — hand soap, body wash, mouthwash, hand sanitizing wipes, household products — and it's easy to see why many of us consider bacteria to be nothing more than a germ-causing antagonist we must avoid and fight at every turn.

However, most of the bacteria in the gut are good health-promoting bacteria.

Our bodies naturally host trillions of bacteria, which play a crucial role in promoting proper function and overall health. Among these numerous microorganisms are beneficial bacteria (probiotics) that live in our gut.

These living gut bacteria are essential for breaking down food, absorbing vitamins and nutrients, and maintaining a healthy balance of gut flora.

Assisting these probiotics are prebiotics, which are special types of dietary fiber. Prebiotics also come from the foods we eat and are essential for helping the good bacteria do their job. Prebiotics come from high-fiber foods such as beans, bananas, oatmeal, onion, garlic, asparagus, legumes, and apples with the skin.

The Bottom Line

Just as there are no two people exactly alike, there are no two digestive systems that are precisely the same. Your gut may benefit from taking probiotic supplements and find them to be a boon for digestive health, while someone else might have an altogether different experience.

Too many probiotics can be bad for your health if you suffer from a weakened immune system, serious illness, or have recently had surgery.

Getting informed, researching, and consulting your physician to minimize allergic reactions and side effects are all good practice so that you can achieve optimal gut health now and for years to come.

And, as always, you can get gut updates and stunning nature imagery from our popular Facebook page. Also, scroll down for our best gut articles.

Research Citations

  • Fijan, Sabina. Microorganisms with Claimed Probiotic Properties: An Overview of Recent Literature. Int J Environ Res Public Health. 2014 May; 11(5): 4745–4767. Published online 2014 May 5. doi: 10.3390/ijerph110504745
  • Ritchie ML, Romanuk TN. A Meta-Analysis of Probiotic Efficacy for Gastrointestinal Diseases. PLoS One. 2012;7(4):e34938. doi: 10.1371/journal.pone.0034938. Epub 2012 Apr 18.
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