Written by Dr. Valentina Quintana MD on
April 2, 2022
Reading Time: 6 minutes

Medically Reviewed by our Medical Affairs Team

Written by Dr. Valentina Quintana MD on:

Do you ever feel like your mind becomes foggy when you eat yogurt or drink anything with probiotics?

Like you can’t think straight? If so, you’re not alone. Many people report feeling this way, especially after taking probiotics.

In this blog post, we’ll explore the causes of probiotics brain fog, its symptoms, and the remedies that can help clear the fog.

We’ll also discuss how probiotics can affect cognitive function and why they might be causing these side effects.

So, if you’re curious about probiotics and brain fog, keep reading!

What exactly is brain fog?

Brain fog or mental fog is a term used to describe feeling like your mind is cloudy and you can’t think straight.

It’s a general term used to describe feeling out of it, groggy, or not being able to focus.

How long brain fog lasts varies from person to person — some people experience brain fog for only a few days, while others may deal with it for a few weeks and even months. 

Brain fog is also sometimes associated with symptoms like forgetfulness, difficulty concentrating, and lack of energy.

While brain fog can be caused by many things – from stress to poor diet – in this blog post, we’ll focus on probiotics and their potential link to brain fog.

What exactly are probiotics?

Probiotics are live bacteria and yeasts that line the gut and support digestive health.

They’re often called “good” or “healthy” bacteria because they help break down food, produce D-lactic acid, keep harmful gut bacteria in check, and support the immune system.

Probiotics can be found in some foods like yogurt and sauerkraut, as well as dietary supplements and probiotic-containing drinks.

How do probiotics work?

Probiotics work by interacting with the gut microbiome – the trillions of bacteria that live in our guts.

The gut microbiome is thought to play a role in everything from digestion and metabolism to mood and cognitive function.

That’s why probiotics are being studied for their potential effects on things like anxiety, depression, and even memory.

So far, the results have been mixed, but there’s still a lot of research to be done.

Can probiotics cause brain fog?

There’s no definitive answer to this question yet, but there is some evidence that probiotics might be linked to brain fog.

One study, for example, found that probiotics caused cognitive problems in mice.

The mice that were given probiotics performed worse on tests of memory and learning and had less energy than the mice that didn’t get probiotics.

Another study found that probiotics caused changes in the gut microbiome of 22 out of 30 participants.

The report showed that the participants who complained of brain fog, increased gas, and bloating have bacterial colonies in their small intestines with levels of D-lactic acid that are higher than normal.

The abnormal increase of D-lactic acid is argued to be the cause of a specific probiotic bacteria, lactobacillus, potentially developing lactic acidosis, also known as metabolic acidosis.

D-lactic acidosis is the build-up of lactic acid in your bloodstream when your oxygen levels run low in the body cells that surround your metabolism. 

Also, it is noted that D-lactic acid can negatively impact brain cells and, therefore, a person’s cognitive function.

However, these are just preliminary studies, and more research is needed to confirm a link between probiotics and brain fog, especially when it comes to small intestinal bacterial overgrowth.

What are the symptoms of probiotics brain fog?

The symptoms of probiotics brain fog can vary from person to person, but they often include feeling “out of it,” groggy, or unable to focus.

You might also experience symptoms like forgetfulness, difficulty concentrating, and lack of energy.

Some of the most notable symptoms besides a foggy brain are the increase in bloating and flatulence. 

If you’re experiencing any of these symptoms, it might be a good idea to talk to your doctor or probiotics specialist.

What are the remedies for probiotics fog?

There are a few things you can do to clear the fog caused by probiotics and improve your overall brain health and cognitive function, such as the following:

Improve your diet

Eating a healthy diet is one of the best things you can do for your brain and overall health.

Make sure to eat plenty of vegetables and fruits as well as whole grains and lean protein. Avoid processed foods, sugary snacks, and excessive alcohol.

For gut health, aim to consume naturally probiotic-rich foods and drinks like the following:

  • Sauerkraut
  • Miso
  • Tempeh
  • Kimchi
  • Sourdough bread
  • Some cheeses (i.e., cheddar, feta, and gouda)
  • Greek yogurt
  • Kefir
  • Kombucha

However, take note to consume these types of food and drinks moderately, especially if you think that probiotics do cause your brain fog.

Drink enough water

Drinking enough water is essential for overall health, especially for brain function.

Studies show that dehydration is one of the huge triggers of brain fog. So, make sure to consume enough water throughout the day.

If you’re not a fan of drinking water, but you want to make it a habit, set reminders on your smartphone or smartwatch so that you get reminded every time it’s time to drink a glass of water.

Get enough sleep

It’s no secret that getting enough sleep is important for your mental health and physical wellbeing, but especially your cognitive function.

Aim to get around seven to eight hours of quality sleep each night.

Most people who sleep less than seven hours a night report feeling more tired, stressed, and foggy-headed.

Exercise regularly

Exercising regularly is another great way to improve your overall health, especially your brain health.

Not only does exercise help keep your body healthy and fit, but it’s also been shown to improve cognitive function, mood, and sleep quality. 

If you’re not sure where to start with a regular exercise routine, try starting with a brisk walk or light jog for 30 minutes, three times a week.

Train your brain

Just as you work out your body, it’s important to also train your brain.

Challenge yourself with new activities or puzzles that require focus and concentration. Play games that improve cognitive function, like chess or Sudoku.

Get more organized

One of the best ways to reduce stress and anxiety, which can both lead to brain fog, is by getting more organized.

Start by decluttering your home and office spaces. Create a filing system for your paperwork, and make sure everything has a specific place where it belongs.

Take breaks throughout the day.

When you’re feeling overwhelmed and bogged down by work or schoolwork, it’s essential to take a break.

Get up and walk around for a few minutes, or step outside for some fresh air. Stretch out your body and do some deep breathing exercises to refresh your mind.

Reduce your stress levels

Stress can have a negative impact on your mental health and cognitive function.

There are a number of things you can do to reduce your stress levels, such as the following:

  • yoga
  • meditation
  • journaling
  • deep breathing exercises
  • a full body massage
  • doing a hobby that you love
  • spending some time with nature  

If you find that stress is a significant contributor to your brain fog, try incorporating one or more of these activities into your daily or weekly routine.

Other Probiotics Side Effects

Aside from brain fog, probiotics can also cause other side effects, such as the following:

  • Excessive flatulence
  • Stomach cramps or pain
  • Bloating
  • Diarrhea
  • Nausea
  • Vomiting
  • Constipation
  • Headache
  • Dizziness
  • Allergic reaction (such as a rash)

If you experience any of these side effects after taking probiotics, stop taking them and speak with your doctor.

Some probiotics are known to cause more severe side effects than others. So, it’s important to do your research before choosing a probiotic supplement to take or talk to a nutrition specialist to get professional advice.

What To Know Before Taking A Probiotic Supplement

When looking for a probiotic supplement to take, it’s essential to keep the following in mind:

  • The probiotic strain(s)
  • The dosage
  • Whether or not it’s dairy-free
  • If there are any potential interactions with the medications that you’re taking.
  • Bacterial imbalances may come from probiotic supplements.
  • There is not enough data that support or oppose probiotics.
  • Probiotic supplements may cause more harm than good to people who are immunocompromised.
  • The Food and Drug Administration (FDA) does not regulate probiotics yet.
  • If you are not confident whether or not you should take a probiotic supplement, it’s always better to eat probiotic-rich food than swallow the pill. 

Probiotics can be taken in pill form, as a powder that you add to water or juice, or as part of a food product.

Not all probiotics are created equal. So, it’s important to do your research on the probiotic strains included in the supplement before taking it.

Also, be sure to follow the dosage instructions on the label. If you’re not sure how to take the probiotic supplement, speak with your doctor or a nutrition specialist.

Some probiotics can cause interactions with certain medications. So, if you’re taking any prescription medications, it’s important to check with your doctor before taking a probiotic supplement.

Finally, probiotics are not recommended for people who are lactose intolerant, have irritable bowel syndrome, or have inflammatory bowel disease.

The Bottom Line

So, probiotics can cause brain fog in some people, especially when D-lactic acid builds up in their small intestines.

While the cause is not yet fully understood, it’s thought that probiotics may cause mental fog due to the fact that they can imbalance the gut microbiota, also called small intestinal bacterial overgrowth, which causes D-lactic acidosis.

There are a number of things you can do to reduce your risk of experiencing brain fog while taking probiotics, such as taking a probiotic supplement that contains strains that have been shown to be beneficial for cognitive function, reducing your stress levels, and avoiding probiotics if you are lactose intolerant.

If you experience any severe side effects after taking probiotics, stop taking them and speak with your doctor.

Before starting any probiotic supplement, make sure to do your research and speak with a doctor or nutritionist if you have any doubts.

If you want to learn more about brain fog and how to cure brain fog fast, check out these educational blog posts and feel free to join this online community of brain health advocates.

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