What Is Brain Fog? Symptoms, Causes, and Treatment

Do you ever notice that your ability to think feels sluggish or fuzzy? You might be experiencing what’s commonly known as “brain fog.” While not technically a medical or scientific term, it describes a temporary sensation of reduced mental acuity.

The emergence of hustle culture, which created legions of overworked achievers, brought awareness to the cognitive challenges that go with it. Lingering brain fog has also been a common side effect during recovery from the COVID-19 viral illness. Brain fog related to menopause can lead to trouble with concentration and difficulty remembering recently learned verbal information, such as the name of someone you’ve been introduced to. Fatigue and certain medical conditions and treatments, such as cancer and chemotherapy, can also cause hazy thinking and cognitive problems.

More and more research is being undertaken to better understand brain fog, a term that’s almost as vague as brain fog itself. Read on to learn more.

Brain fog isn’t something doctors diagnose their patients with.

“Brain fog is a broad term used to describe some common cognitive symptoms that folks face,” says Shehroo Pudumjee, PhD, a neuropsychologist at the Cleveland Clinic Lou Ruvo Center for Brain Health in Las Vegas. These can be varied but generally center on the idea that your “thinking or memory isn’t as efficient or effective as it used to be,” she says.

Dr. Pudumjee says that brain fog manifests as “cognitive inefficiencies” — meaning, you’re having a tough time calling up your cognitive resources as well as you did in the past.

You may notice difficulty with:

• Attention
• Concentration
• Learning
• Short-term memory

What that might look like can differ between people, but here are some things you may experience as a consequence of brain fog, according to Pudumjee and Danielle Wilhour, MD, an assistant professor of neurology at the University of Colorado School of Medicine in Denver.

• You struggle with multitasking.
• You have more trouble grasping concepts or learning than you did before.
• Words arrive at the tip of your tongue, but you can’t seem to find them.
• You may feel as if you’re in a dream or trancelike state.
• You walk into a room and can’t remember what task you set out to accomplish.
• You forget details of conversations.
• You can’t absorb content as well as you used to.
• You’re easily pulled off task or distracted.

One of the challenges with understanding brain fog is that there are so many potential causes, and the term "brain fog" alone doesn’t tell doctors what exactly is going on. That said, here are a few common causes to consider.

Hormonal Changes

Diet Challenges

If you’re eating a restricted diet, not consuming adequate vitamins and minerals may result in some brain fog, says Pudumjee. Specifically, a deficiency in B12 or iron can cause anemia, which can decrease your energy levels and tangentially affect cognition, says Wilhour.

Medications

Certain medications may cause brain fog as a side effect. For example, topiramate (Topamax), which is sometimes used to treat migraine (though it’s more commonly used to prevent seizures), can leave you feeling mentally murky. “I warn patients that it can cause cloudy thinking, confusion, and word-finding difficulty,” Wilhour says.

In addition, multiple medications — also called polypharmacy — can be another factor in brain fog, she says. People experience side effects in different ways, but if you’ve noticed brain fog after starting a new drug, ask your doctor or pharmacist if cognitive issues are a possible side effect. (Don’t stop taking prescribed meditation without first consulting your physician.)

Chronic use of alprazolam (Xanax) and diazepam (Valium), taken for anxiety, can cause brain fog when used for a long time. Even if you used to be fine with it, the older you get the harder it is to metabolize.

Chemotherapy

Certain Medical Conditions

Wilhour notes that brain fog may emerge with many medical conditions, including postural orthostatic tachycardia syndrome, anemia, diabetes, depression, anxiety, and autoimmune conditions such as multiple sclerosis, chronic fatigue syndrome, celiac disease, and lupus.

COVID-19

MCI may proceed to dementia, but brain fog isn’t known to.

If brain fog persists past a couple of weeks, talk to your doctor, Pudumjee advises. Brain fog can be normal, especially if you’re stretched thin. But if it begins to affect your quality of life, you should seek professional medical guidance, adds Wilhour.

Your doctor will take a medical history and (possibly) do blood work, as well as ask you questions about your lifestyle to examine your habits around physical activity, diet, stress management, and sleep. To treat brain fog, it’s important to address any existing underlying medical conditions that may impact your cognitive function.

Beyond that, these expert-recommended lifestyle tweaks may help you beat brain fog.

Exercise Regularly

Stay active and aim for 150 minutes of moderate-intensity physical activity per week, if you’re healthy. (Walking counts.) “Exercise activates the brain but also tires you out, helping you sleep better at night,” says Pudumjee.

Sleep Well

Aim for at least seven hours of sleep per night, says Wilhour. And maintain a consistent rest schedule. “Go to bed and wake up at the same time,” she advises. You might want to stay up late to get more done, but it will pay off to put the laptop away or turn off Netflix. “In general, you won’t be as efficient the following day,” says Wilhour. “Sleep should be a priority for everyone.”

Manage Your Stress

“We have a primitive brain and a more advanced brain. When in a state of chronic stress, the primitive brain takes over, and we can’t use our higher thinking functions as well,” explains Wilhour. Getting a handle on stress will help you stay more in the thinking brain.

Try Cognitive Therapies

The meditative practice of mindfulness — focusing on one thing and being present — has been associated with stress reduction, decreased depression, and relief for menopausal symptoms, all of which can contribute to brain fog.

Activities that exercise your brain — reading books, doing crossword puzzles, playing games or instruments — can stimulate and support cognitive health and may help you manage brain fog.

Take Nutrition and Diet Into Account

Inflammation is thought to be related to brain fog, and an anti-inflammatory diet might counteract inflammatory effects in the body. This means limiting or avoiding highly processed foods and red and processed meats, and following a plant-based or Mediterranean-style diet centered on whole grains, fruits, and vegetables loaded with antioxidants, and healthy fats like omega-3 fatty acids.

Moderate Caffeine and Alcohol

Stay Connected

Brain fog — that fuzzy, foggy feeling when you’re not at your sharpest — isn’t a medical term but researchers are increasingly trying to better understand it. Factors like stress, hormonal changes, diet, sleep, and some medical conditions and medications can lead to this temporary cognitive state. If you’re struggling and feeling mentally sluggish, there are ways to manage it with lifestyle changes and other therapies.