What Is Brain Fog?

A Group of Cognitive Symptoms With Many Possible Causes

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Brain fog isn’t actually a medical condition, but rather a term used to describe the feeling of being mentally sluggish and fuzzy. It can be a symptom of other health conditions.

Brain fog feels like a lack of mental clarity; it can affect your ability to focus and make it difficult for you to recall things, says Sabrina Romanoff, PsyD, a professor and clinical psychologist in New York City.

Sabrina Romanoff, PsyD

Ultimately, brain fog can impact the way you feel about yourself. Individuals often do not feel like themselves as the loss of mental sharpness feels foreign to them.

— Sabrina Romanoff, PsyD

Causes of Brain Fog

A number of factors and health conditions can cause brain fog, including:

Brain Fog and COVID

COVID-19 can cause inflammation in the brain, which can affect the ability of neurons in the brain to communicate with each other, resulting in brain fog. However, the stress, anxiety, isolation, and threat of the coronavirus pandemic can also indirectly cause brain fog, since it can be exhausting for your brain, says Romanoff.

It is not unusual for brain fog to be caused by a combination of two or three of these factors since they often go hand in hand. 

For instance, depression can lead to a lack of sleep or vice versa. Similarly, stress can affect your sleep and cause depression. Perimenopause may be accompanied by lack of sleep and depression.

So, how long does brain fog last? If your brain fog is caused by a lack of sleep or a nutrient deficiency, your brain fog will likely dissipate when you get adequate sleep or when you fulfill your vitamin requirements with supplements, for instance.

However, the timeline is less clear for brain fog associated with other conditions. In the case of COVID brain fog, for example, researchers still don't know how long it typically lasts. Some people experience relief after a few weeks or months, whereas, for others, it's longer-lasting.

Symptoms of Brain Fog

Brain fog symptoms may include difficulty with cognitive functions such as:

Brain fog can also cause symptoms like headaches and mental exhaustion.

Tips and Tricks to Reduce Brain Fog

These are some steps you can take to reduce brain fog:

  • Get enough sleep: Sleep is important for your brain and body to clear out unhealthy toxins that can contribute to brain fog. Try to follow a fixed sleep schedule and make it a point to get seven to nine hours of sleep every night. Avoid using electronic devices like your mobile, laptop, or television before you go to sleep.
  • Try new things: Keep your mind engaged with mentally stimulating activities and make an effort to try new things. For instance, take a different route to work, try a different approach to a task you do regularly, or listen to different music. This can help increase the production of a brain chemical called norepinephrine, which stimulates the brain.
  • Avoid multitasking: Multitasking can drain your energy and lower your productivity, especially if you’re trying to do two activities that require conscious thought. Instead, try focusing on one thing at a time.
  • Work on your memory: If you’re prone to forgetting things, try using different tricks to improve your memory. For instance, rhymes, mnemonics, or visual or verbal cues can help you remember important things. You can also try repetition; for instance, if someone tells you their name, saying it back to them can help you remember it.
  • Take mental breaks: Make it a point to take a couple of mental breaks during the day, where you don’t think about anything and be in the moment. You can close your eyes, take a short walk, or look out your window.
  • Focus your attention: If you get distracted by multiple things or lose focus, try to slow down and focus all your attention on one task. Then, work on completing that task, no matter how small. 
  • Stay socially active: Participating in social activities can improve your mood, memory, and cognition.
  • Engage in deep thought: Exercise your mind by spending a little time engaged in deep thought each day. For instance, if you have read an article, spend 10 minutes thinking about the article's contents.
  • Try meditation: Meditation can help reduce stress and relax your brain and body.
  • Exercise regularly: Staying physically active can improve your mental health.
  • Follow a healthy diet: A healthy diet, such as the Mediterranean diet, can help with memory, cognition, and brain health. 
  • Avoid alcohol and drugs: These substances can impair your senses and adversely affect your brain.
  • Receive medical treatment: If you suspect your brain fog may be related to depression, a thyroid disorder, a nutrient deficiency, or any other medical condition, be sure to consult with a doctor or health professional right away.

A Word From Verywell

Brain fog is the uncomfortable feeling of being spaced out. It can make it difficult for you to focus on tasks at hand, remember things, or pay attention to what’s going on around you. It can also make you feel out of sorts and unlike yourself. 

Many people may experience the occasional bout of brain fog if they haven’t slept well, or if they have allergies and have taken antihistamine medication, for instance. However, some health conditions may cause persistent brain fog. 

Discuss your symptoms with a healthcare provider; they may be able to determine what’s causing the brain fog and suggest a treatment plan accordingly.

4 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Cedars-Sinai. How COVID-19 compromises brain function.

  2. Krause AJ, Simon EB, Mander BA, et al. The sleep-deprived human brainNat Rev Neurosci. 2017;18(7):404-418. doi:10.1038/nrn.2017.55

  3. Sultan S, Taimuri U, Basnan SA, et al. Low vitamin D and its association with cognitive impairment and dementiaJ Aging Res. 2020;2020:6097820. doi:10.1155/2020/6097820

  4. Harvard Health Publishing. Brain fog: Memory and attention after COVID-19.

Additional Reading

By Sanjana Gupta
Sanjana is a health writer and editor. Her work spans various health-related topics, including mental health, fitness, nutrition, and wellness.