What Is Brain Fog and What Does It Do?

01/30/2023 | 5 min. read

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Have you ever woken up one day and just felt off? You might be experiencing a type of cognitive dysfunction known as brain fog. Here’s what you need to know about brain fog and what you can do about it.

What Is Brain Fog?

Brain fog refers to feeling mentally “foggy,” “fuzzy,” and “sluggish.” Brain fog is not a medical condition, although it may be a symptom of other health issues. It can be frustrating as it causes you to not feel like yourself and may impact your ability to successfully complete daily tasks and achieve your goals.

What Are the Effects of Brain Fog?

Brain fog can contribute to cognitive issues, including but not limited to:

  • Difficulty with focusing on a thought or idea
  • Difficulty with recalling information
  • Difficulty with paying attention
  • Difficulty with multitasking
  • Difficulty with carrying on a conversation

What Are the Causes of Brain Fog?

Since brain fog isn’t a medical condition on its own but a symptom of other health issues, it’s essential to figure out the root cause of your brain fog so that you can take steps to address it.

Brain fog can be caused by a whole host of different medical conditions and health issues, but here are some of the most common causes:

Lack of Sleep

The body and specifically the brain need sleep in order to function properly. A lack of sleep can impact your brain function, causing you to feel foggy, drowsy, and fatigued.

Poor Diet

The body also needs proper nutrition to power the brain. A poor diet that’s lacking in vitamin B-12 can contribute to brain fog. One of the most common causes of brain fog is a food allergy.


Stress wreaks havoc on how you feel both physically and mentally. Physically, it can contribute to higher blood pressure and a weakened immune system. Mentally, it can contribute to mental fatigue and brain fog.

Mental Health

Mental health issues also affect how you feel both physically and mentally. Depression, for example, can cause physical symptoms like chronic pain and digestive issues. Poor mental health can contribute to poor concentration and brain fog.

Hormonal Changes

Changes in hormone levels can also affect brain function. For example, increased levels of progesterone and estrogen during pregnancy are known to impact short-term memory and other related memory problems.

Alternatively, decreased levels of estrogen during menopause can also impact memory, lead to forgetfulness, and reduce concentration.


Medications contain chemicals and compounds that can affect your brain chemistry, resulting in brain fog. This equally applies to over-the-counter (OTC) medications, prescription medications, and supplements.

Everyone reacts differently to different medications, but some examples of medications known to cause brain fog include opioid analgesics, tricyclic antidepressants, and gabapentin.

Viral Infections

Brain fog could also be a sign of a viral infection. Viral infections like COVID-19, SARS, and H1N1 have been known to cause brain fog in addition to other symptoms such as cough, headache, fever, sore throat, stuffy nose, body aches, and chills.

Should You See a Doctor About Brain Fog?

While a single day of brain fog may not warrant a trip to the doctor’s office, you should speak with your physician if you’re experiencing persistent brain fog or brain fog that’s accompanied by other symptoms.

During the appointment, your doctor will likely begin with a physical examination to pin down the cause of your brain fog. They will ask about your mental clarity, mental health, diet, exercise habits, and medications or supplements.

Be sure to provide your doctor with information regarding when you began experiencing the brain fog and any other symptoms you might have. Even a seemingly unrelated issue could provide them with a clue as to the cause of your brain fog.

Based on your physical, your doctor may also decide to run some blood tests. Blood tests are able to detect thyroid issues, nutritional deficiencies, infections, and abnormal glucose levels that could be contributing to your symptoms.

If your blood test results come back normal, your doctor may also consider running additional tests, including imaging tests like X-rays, MRI scans, and CT scans, along with sleep studies and allergy testing.

How To Deal With Brain Fog?

When treating brain fog, you first need to consider the root cause. For example, if your brain fog is caused by a new medication, consult your doctor and stop taking the medication. If you’re experiencing some of the potential side effects such as a lack of sleep, make sure to get enough sleep and take the necessary steps to improve your quality of sleep.

However, if you’re unsure of the root cause of your brain fog or if it’s caused by an issue that’s difficult to treat, here are some tips to help you deal with brain fog:

Switch Things Up

Even without brain fog, it can be challenging to do the same thing over and over again. To make things easier, switch up your tasks and routines so that they’re more mentally stimulating.

Focus on One Thing at a Time

Multitasking can drain your brain and make it difficult for you to be productive. Instead, focus all of your energy on one item before moving on to the next item on your list.

Take a Mental Break

Sometimes, your brain needs a break during a busy day. If you’re feeling foggy, try getting outside, meditating, or exercising.

Live a Healthy Lifestyle

Avoid alcohol and drugs that can negatively impact your brain function and make you feel even worse. Eat a proper diet and use supplements to fill in the gaps when needed.


At Healthy Directions, we emphasize the importance of acknowledging symptoms. If brain fog is a regular occurrence for you, you should talk to your doctor about it and any other symptoms you’re experiencing.

However, if your brain fog only occurs every now and then, prevent it from happening in the future by getting enough sleep, eating a healthy diet, and following a healthy lifestyle to help get rid of brain fog.


Understanding Chronic Brain Fog | Psychology Today

Stuck in a Brain Fog? Look in Your Medicine Cabinet | Harvard Health

COVID-19 'Brain Fog' Inspires Search for Causes and Treatments |

Healthy Directions Staff Editor