7 Foods That Cause Brain Fog

Written by


Reviewed by

Camille Freking, MS Translational Pharmacology and Clinical Research

Do you ever have one of those days when your mind can’t get on track? No matter how hard you try, it’s like your brain is lost in a field of thick fog and doesn’t know left from right? 

That feeling is commonly known as brain fog, and you’re one of the estimated 600 million people worldwide that regularly experience it. 

There is still a lot that we don’t understand about brain fog. It’s recently become a major health concern in the aftermath of the COVID-19 pandemic. Brain fog is one of the most common symptoms of “long COVID,” so there could be more than 600 million people experiencing it. 

Perhaps the worst thing about brain fog is that it’s challenging to treat properly. Keeping your brain well supplied with essential nutrients might help reduce the symptoms, but there has yet to be an established cure or preferred treatment method. 

Therefore, the best way to treat brain fog is by learning about its triggers and avoiding them at all costs.  


What Is Brain Fog?

Technically, brain fog isn’t a diagnosable medication condition — it’s just the everyday term for experiencing cognitive difficulties. People who’ve encountered brain fog usually describe it as feeling mentally sluggish, fuzzy, confused, and forgetful. You generally feel spaced out and lack clarity, making it difficult to concentrate, recall information, or learn.  

The root cause of brain fog is generally neuroinflammation in the brain or spinal cord. Neuroinflammation often results from the central nervous system's immune system releasing excessive inflammation to combat a perceived threat. In some cases, this perceived threat can result from something you ate. 


The 7 Foods That Can Cause Brain Fog

Your brain relies on you to follow a healthy diet that supplies the nutrients it needs to function properly. Straying from that diet or eating unhealthy foods can cause cognitive decline, including brain fog. 

Here are seven common foods that have an established negative relationship with brain fog:

1. Pasta 

Refined carbohydrates are sugars or grains stripped of most of their nutrients, bran, and fiber. Pasta, white bread, pizza dough, pastries, white rice, sodas, sweets, and cereals are some of the most common foods with refined carbs. Eating foods like this aren’t just a hazard for your waistline; they can be dangerous for your brain too. 

Refined carbs have virtually no nutritional value, so your digestive system quickly breaks them down. As a result, they can hit your bloodstream very quickly and cause an enormous spike in your blood sugar. The dramatic increase in your blood sugar can often trigger an inflammatory response by your immune system. The inflammation can reach your brain and cause symptoms of brain fog. 

2. Hot Dogs 

Processed meats such as hot dogs, sausage, bacon, pepperoni, bologna, and jerky are pumped full of various compounds to prolong their expiration and maintain their color. The most popular of these compounds are different salts, including sodium nitrate, nitrite and sodium, and potassium benzoate. 

The chemical compounds most often found in processed meat are classified as carcinogens. That means they have the potential to cause cancer in addition to a whole host of other health problems that can include brain fog. Despite this classification, the Food and Drug Administration has approved the use of these additives in regulated amounts. 

3. Aspartame 

Aspartame, saccharin, and sucralose are three of the most popular artificial sweeteners in the world. Artificial sweeteners skyrocketed in popularity as a potential way to stem the obesity epidemic. The idea was that they could provide the sweetness of sugar without the calories. A noble ambition for sure, but they’re not always the best option.

Aspartame in particular has been linked to symptoms of brain fog, dizziness, and behavioral effects like mood changes and irritability. 

4. Dairy 

Having an allergy or general sensitivity to dairy is extremely common. The primary reason for these issues is a protein called casein. Some people cannot break down this sugar molecule properly, which triggers an allergic reaction in their bodies. 

In most cases, this reaction will manifest through gut health and digestive upset. However, the response can sometimes occur in the central nervous system. The inflammation from the reaction can travel through the nervous system into the brain and cause brain fog.  

5. Bread

Gluten is a protein in wheat, rye, and barley products. It plays several crucial roles in bread making, including helping to hold the bread together, trapping gas during fermentation, allowing the dough to rise, and giving bread its unique texture. 

The problem is that gluten can trigger an inflammatory response in the body. Even people without gluten sensitivity can experience an elevated level of inflammation after ingesting it. The excessive inflammation could potentially reach your brain, which could cause neuroinflammation and trigger brain fog. 

6. MSG

Monosodium glutamate (MSG) is a common flavoring agent in condiments, salad dressing, canned goods, soups, fast food, and processed food. MSG is often added to these foods as a flavor enhancer but is one of the food-based triggers of brain fog. 

The active ingredient of MSG is free glutamic acid which is converted into glutamate by your body. Glutamate is a neurotransmitter that helps transmit between your neurons. While that might sound beneficial, too much glutamate in your brain can trigger irritation and even harm neurons in the long run. 

As if that weren’t bad enough, excessive glutamate can exhaust your natural supply of glutathione and other antioxidants. Without their protection, you’ll be at a higher risk of experiencing free radical damage and oxidation.  

7. Alcohol

The reason why alcohol makes this list isn’t for the reason that you might be thinking. Clearly, alcohol profoundly affects your mental capacities, and that is why many people reach for it. But the type of brain fog alcohol causes isn’t the same as having too many drinks or going through a rough hangover.

Plenty of alcoholic beverages (especially beer) contain gluten, which can cause inflammation in your body. It can also contain an extremely high concentration of histamines that can significantly alter blood flow

The drastic change in blood flow can often trigger an inflammatory response from your immune system. The inflammation can reach your central nervous system and cause brain fog. 


What Else Can Cause Brain Fog?

As mentioned earlier, brain fog is commonly caused by neuroinflammation within your brain or spinal cord. Neuroinflammation can result from an injury, infection, or aging. The various foods listed above are one potential type of trigger for neuroinflammation, but let’s look at some more.

  • Medications. Certain medications that can impair brain function include benzodiazepines, antipsychotics, opiates, antidepressants, sedatives, and anticholinergics. Taking these drugs can alter the communication between your neurons and cause brain fog symptoms. That said, never stop taking your medications without your doctor's guidance. If you're worried your medication may be causing brain fog, talk to your doctor about your symptoms and the possibility of a lower dosage or change in prescription.
  • Medical Conditions. Multiple sclerosis (MS) impacts how your central nervous system and brain communicate with each other and the rest of your body. It’s common for people with MS to also experience issues regarding memory, attention span, and language. Other conditions that cause brain fog include anemia, depression, Alzheimer’s disease, lupus, Sjogren syndrome, and COVID-19. 
  • Stress. Constantly worrying and being stressed will use up much of your mental bandwidth, severely exhausting your brain. When your brain is overwhelmed, it can naturally start to flounder and lose some of its cognitive focus.  


How Is Brain Fog Treated?

There are currently no known cures for brain fog or the neuroinflammation that causes it. Fortunately, the brain naturally attempts to combat neuroinflammation by producing cytokines, chemokines, reactive oxygen species, and secondary messengers. It’s possible that making a few lifestyle changes can reduce the effects of brain fog or address the underlying issues that are causing neuroinflammation. 

Here are a few ways that you might be able to fight back against brain fog:

  • Relax your mind by meditating, taking a nap, socializing, or going for a walk. Your brain is running 24/7, so it can get a little exhausted from time to time. Sometimes it just needs a little downtime to recalibrate, replenish, and recharge.  
  • Physical exercise can help improve your cognitive health in various ways, including learning, problem-solving, and overall thinking. Going for a run might help to clear up brain fog, but you consider creating a workout routine to get exercise regularly. 


Rejuvenate Your Mind With MOSH

Going through life with brain fog can make the most simple tasks seem impossible to complete. While there are a few vitamins and supplements that might be able to help, there is currently no known cure for brain fog or neuroinflammation. 

That means that the best treatment is to avoid anything that might trigger brain fog. Avoiding certain foods, getting enough sleep, and managing your stress are a few ways that you can reduce your risks. 



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