Strategies for Busting Up Brain Fog

Brain fog has many symptoms and many possible underlying conditions

A drawing of a woman holding her head with a fog surrounding her

Have you ever just lost your train of thought while you’re in the middle of an activity? Or maybe you’re caught up in conversation when suddenly you have trouble remembering that darn word or detail that just slipped out of reach. These events are common as you get older. But if your thinking has been affected suddenly and gradually worsens so you have difficulty focusing or putting your thoughts into words, you may be experiencing what people call brain fog.


Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy

Neuropsychologist Kamini Krishnan, PhD, explains why brain fog has become a popular term of the moment and why brain fog may happen as a symptom of other common conditions.

What is brain fog?

Brain fog doesn’t have a single official definition or medical diagnosis. Instead, it’s often a cluster of cognitive symptoms that people experience. Brain fog can be a lot of things to different people, too. It can include any or all of the following:

  • Trouble focusing.
  • Difficulty staying attentive.
  • Trouble remembering familiar details like names, places or words.
  • Slow reaction times and information processing.
  • General fatigue or lethargy.
  • Cloudiness in judgment.
  • Frequent loss of train of thought.

“When you have deficits in these areas, you may feel like you’re having memory problems. But it’s more of a problem in acquiring and maintaining the right information,” says Dr. Krishnan. “If you’re not getting the right information, you can’t be expected to hold onto it.”

What causes brain fog?

So, what’s causing the blockage of information? Well, there’s no definitive answer. One idea is that your body’s immune system response could cause inflammation in your brain. When inflammation occurs, this could cause a temporary blockage in processing information. Brain fog can also be caused by chronic stress, hormonal changes or blood sugar imbalances.

“Brain fog is a sort of manifestation of some type of inflammation or chronic stress response,” explains Dr. Krishnan. “Chronic stress can have secondary effects. It impacts your sleep, your nutrition and your physical ability. Those secondary issues can lead to or be associated with psychiatric disorders.”

Here are some common conditions associated with brain fog symptoms.


You experience a range of hormonal changes during each trimester. When these hormonal changes occur, your brain tries to restore balance by releasing and suppressing certain hormones to level everything out. You may experience brain fog because of this constant flux of hormones or because of other stressors that can occur even early in your pregnancy.

“In your first trimester, you may have more nausea, poor nutrition, insomnia or lack of sleep, or other increased stressors for a variety of reasons. All of these things can manifest as brain fog,” says Dr. Krishnan.


Brain fog has been getting its 15 minutes of fame thanks to COVID-19 and all its related symptoms. In fact, brain fog is one of the top three symptoms often listed by long-haulers, who experience prolonged symptoms or delayed symptoms weeks and sometimes months after initial infection.

“People who have been in the ICU or required more severe forms of treatment tend to experience more brain fog,” notes Dr. Krishnan.


The trouble, Dr. Krishnan points out, is that long-haulers and people who’ve recovered from COVID-19 often also experience other symptoms that can lead to brain fog. This includes trouble sleeping, increased stress or mood levels, or a significant change in their diet or nutrition.

“All of these factors can also contribute to brain fog,” he says.

So, it’s difficult to pinpoint exactly what’s causing the brain fog — COVID-19 or these other closely related symptoms. One major hypothesis is that brain fog related to COVID-19 may actually be a result of having a cytokine storm (also known as cytokine release syndrome).

In a cytokine storm, your body floods your bloodstream with inflammatory proteins called cytokines. These cytokines help target the virus, or foreign body, that’s causing trouble. But this can also trigger an exaggerated immune system response in other areas of your body, like your brain, and lead to further inflammation.

“While it’s trying to be protective, it can also have negative effects,” says Dr. Krishnan.

Depression and anxiety

Depression and its relation to brain fog is kind of like asking what came first, the chicken or the egg? One can often lead to the other and vice versa. One common reason for this may be because of neuroinflammation caused by the constant activation of your hypothalamus pituitary adrenal pathway.

“That’s your body’s fight-or-flight response,” explains Dr. Krishnan. “If your body is in a constant level of activation, it can have negative side effects and present as depression or anxiety because it has that inflammatory response.”

Brain fog associated with depression or anxiety often feels like constant fatigue or a general sense of malaise.


The same cytokine storm that’s present in some people with COVID-19 can also occur as a result of chemotherapy. Unlike with COVID-19, though, brain fog that’s associated with chemotherapy treatments often goes away in a much shorter time.

“Sometimes, brain fog or cognitive complaints don’t show up until a few years after the start of chemotherapy,” says Dr. Krishnan. “We don’t anticipate this to be a long-term issue. Most people say it gets better as time progresses from the chemotherapy treatments.”


Food sensitivities

Some food sensitivities can also lead to brain fog or its associated inflammatory response. For example, with celiac disease, people will often complain of feeling cloudy or bogged down because of their gluten sensitivity.

Blood-sugar levels

If you have low blood sugar (hypoglycemia), you can feel dizzy, lightheaded, foggy or nervous and unable to concentrate. This is especially true in people with diabetes if their body creates too much insulin. Sometimes, you can even experience low blood sugar levels after having a meal.

Autoimmune conditions

Several autoimmune conditions are also associated with brain fog, including:

“A prolonged attack on the immune system tends to have an impact on an individual’s brain function,” notes Dr. Krishnan.

How can I get rid of brain fog?

In general, there aren’t any known medications or treatments that correct brain fog directly. To immediately address most chronic stressors, Dr. Krishnan suggests focusing on improving your sleep, getting good nutrition and exercising 30 minutes every day, five days a week. These small changes to your everyday life can build up over time and greatly impact your immune system response and reduce inflammation.

“This doesn’t have to be a marathon,” says Dr. Krishnan. “The idea is to challenge yourself every day and reduce any stressors as much as possible in your life.”

Dr. Krishnan also suggests taking mental breaks throughout the day to build up your mental capacity.

“Most of us tend to go, go, go until you hit a point of no return and then you’re fatigued or tired or unable to do things for a day or two,” Dr. Krishnan adds. “We recommend people take 20- to 30-minute breaks even before they’re tired by doing some kind of focused activity like walking, listening to music or closing your eyes and resting.”

If you’ve tried these methods, or you’ve experienced brain fog for some time, you should call your healthcare provider or work with an integrative medicine specialist who can help you make lifestyle changes across several areas that include diet, nutrition, sleep and exercise.

Learn more about our editorial process.

Related Articles

Two friends laughing together
March 26, 2024/Mental Health
No Fooling: The Very Real Health Benefits of a (Good) Prank or Joke

A pro-level laugh can release good-for-you oxytocin, dopamine and endorphins

person pulling open blue curtains to sunshine
March 4, 2024/Mental Health
Not Feeling Like Yourself Lately? How To Get Out of a Funk

Connecting with others, going for a walk or focusing on sleep quality can help more than you might realize

person sitting in a growing flower, as they're watering the pot from above
February 9, 2024/Mental Health
Self-Love: Why It’s Important and What You Can Do To Love Yourself

Like being your own best friend in times of trouble, self-love is an act of self-preservation

person standing on exclamation point holding up a No. 1 finger, wearing cape and mask in front of crowd
February 1, 2024/Mental Health
How To Make the Most of Your ‘Villain Era’

It’s not about embracing your dark side — it’s about showing up for yourself

Silhouette of person turned away from group of people talking
January 23, 2024/Mental Health
How the Grey Rock Method Can Protect You From Abusive People and Toxic Interactions

Like a boring ol’ grey rock, the goal is to be unresponsive and uninteresting to dissuade a harmful situation

person looking at reflection in hand-held mirror
January 22, 2024/Mental Health
9 Signs You’re Dealing With a ‘Narcissist’ (and Why That’s the Wrong Word to Use)

Narcissistic personality disorder is a mental health condition, not an insult

Female sitting on couch staring blankly ahead, with male next to her on couch staring at her
January 19, 2024/Sex & Relationships
The Silent Treatment: Causes and Coping

Whether this behavior is abusive depends on the person doing it and their motivation

Person holding three different masks while looking at a group of diverse people
January 19, 2024/Mental Health
Cracking Code-Switching

Presenting yourself differently in different contexts can be both empowering and isolating

Trending Topics

Person in yellow tshirt and blue jeans relaxing on green couch in living room reading texts on their phone.
Here’s How Many Calories You Naturally Burn in a Day

Your metabolism may torch 1,300 to 2,000 calories daily with no activity

woman snacking on raisins and nuts
52 Foods High In Iron

Pump up your iron intake with foods like tuna, tofu and turkey