Brain fog is a symptom that can be caused by stress, sleep changes, medications, and other factors. It can cause confusion, memory issues, and a lack of focus.
Brain fog itself is not a medical condition but instead a symptom of other medical conditions. It’s a type of cognitive dysfunction involving:
- memory problems
- a lack of mental clarity
- poor concentration
- an inability to focus
Some people also describe it as mental fatigue. Depending on the severity of brain fog, it can interfere with work or school. But it does not have to be a permanent fixture in your life.
There are several explanations for why brain fog happens. Once you identify the underlying cause, you can begin fixing the problem. Here are six possible causes.
1. Stress
Chronic stress can increase blood pressure, weaken the immune system, and trigger depression, according to
When your brain is exhausted, it becomes harder to think, reason, and focus.
2. Lack of sleep
Poor sleep quality can interfere with how well your brain functions, according to
Sleeping too little can lead to poor concentration and cloudy thoughts.
3. Hormonal changes
Hormonal changes can also trigger brain fog, according to
Similarly, a drop in estrogen levels during menopause can cause forgetfulness, poor concentration, and cloudy thinking, according to
4. Diet
Diet can also play a role in brain fog. Vitamin B12 supports healthy brain function, and a vitamin B12 deficiency can bring about brain fog, according to a
If you have food allergies or sensitivities, brain fog
- aspartame
- peanuts
- dairy
Removing trigger foods from your diet may improve symptoms.
5. Medications
If you notice brain fog while taking medication, talk with your doctor. Brain fog may be a known side effect of these medications, according to
Brain fog
6. Medical conditions
Medical conditions associated with inflammation, fatigue, or changes in blood glucose level can also cause mental fatigue. For example, brain fog is a symptom of chronic fatigue syndrome, which involves persistent fatigue for a prolonged period of time, according to
People who have fibromyalgia may experience similar fogginess on a daily basis, according to a
Other conditions that may cause brain fog include:
- anemia
- depression
- diabetes
- Sjögren syndrome
- migraine
- Alzheimer’s disease
- hypothyroidism
- autoimmune diseases, like lupus, arthritis, and multiple sclerosis
- dehydration
- viral infections, like COVID-19
Talk with a doctor if you have a persistent lack of clarity that worsens or does not improve.
A single test cannot be used by a doctor diagnose brain fog. Brain fog may signal an underlying issue, so a doctor will conduct a physical examination and ask about your:
- mental health
- diet
- level of physical activity
- current medications or supplements
You should let your doctor know about other symptoms you might have. For example, someone with hypothyroidism may have brain fog along with hair loss, dry skin, weight gain, or brittle nails.
Blood work can help your doctor identify the cause of brain fog. A blood test can detect the following:
- irregular glucose levels
- poor liver, kidney, and thyroid function
- nutritional deficiencies
- infections
- inflammatory diseases
Based on the results, your doctor will determine whether to investigate further. Other diagnostic tools may include imaging tests to look inside the body, like X-rays, magnetic resonance imaging (MRI), or computerized tomography (CT) scans.
The doctor may also conduct allergy testing or a sleep study to check for a sleep disorder.
Keeping a food journal can help you determine if your diet contributes to brain fog.
If you need help finding a primary care doctor, then check out our FindCare tool here.
Brain fog treatment depends on the cause. For example, if you’re anemic, iron supplements may increase your production of red blood cells and reduce your brain fog.
If you’re diagnosed with an autoimmune disease, a doctor may recommend a corticosteroid or other medication to reduce inflammation or suppress the immune system.
Sometimes, relieving brain fog is a matter of correcting a nutritional deficiency, switching medications, or improving the quality of your sleep.
Home remedies to improve brain fog include:
- sleeping 8 to 9 hours per night
- managing stress by knowing your limitations and avoiding excessive alcohol and caffeine
- exercising
- strengthening your thinking abilities (try volunteering or solving brain puzzles)
- finding enjoyable activities
- increasing your intake of protein, fruits, vegetables, and healthy fats
Brain fog can be frustrating, but relief is possible. You should not ignore your symptoms because if left untreated, brain fog can impact the quality of your life. Once the underlying cause is addressed, your mental clarity can improve.
