Is It Brain Fog...or Long COVID?

Parsley Health
Medically Reviewed
September 28, 2022

How brain fog, long COVID, and inflammation are all connected (and how you can decipher which is which)

When was the last time you felt truly refreshed? How often do you use the phrase, “I’m just tired today?" Are you struggling to remember things? How often are you experiencing headaches or body aches?

Confusion, fatigue, difficulty concentrating… The symptoms of brain fog can be easy to pass off as a part of life, with many of us thinking that they're normal parts our busy lives. But the fact of the matter is that brain fog is a real, quantifiable experience, and it can be indicative of other underlying issues your body is coping with.

While the connection between brain fog, inflammation, and long COVID might seem confusing, understanding them better will actually make them easier to notice, diagnose, and treat.

What is brain fog?

Brain fog is not a medical condition, but a symptom of other medical conditions. This type of cognitive dysfunction can present as:

  • memory issues
  • lack of mental clarity
  • poor concentration
  • an inability to focus

In more severe cases of brain fog, you might even have headaches, problems with your vision, or nausea.

Since brain fog symptoms are so diverse and subjective, medical diagnoses are particularly difficult to make. The symptoms of brain fog can easily be attributed to seasonal allergies, trouble sleeping, stress, and even over-exposure to blue light from all of our various electronic devices.

Another reason why brain fog is difficult to diagnose is that it can be caused by so many factors, like nutrient deficiency, sleep disorders, bacterial overgrowth from overconsumption of sugar, depression, or even thyroid conditions. Other common brain fog causes include eating too much and too often, inactivity, not getting enough sleep, chronic stress, and a poor diet.

If this list of causes looks familiar, it’s because they can also contribute to chronic inflammation.

What is chronic inflammation?

Chronic inflammation is a long-term condition typically caused by underlying issues like autoimmune disorders, exposure to toxins like pollution, and acute inflammation from untreated viruses or injuries. It can exist throughout the body, and its symptoms range from fever and skin rashes to joint and chest pain. It can also disrupt the normal processes of your gut by stunting serotonin development. The lack of this mood-booster hormone can make you feel depressed, which can lead to sluggishness and trouble thinking clearly—also known as brain fog.

That’s right: Inflammation is directly related to brain fog. Because our bodies are a tangled web of “cause and effect,” it can take a comprehensive wellness exam to track down the root cause of chronic inflammation, and therefore brain fog. But what if that root cause was actually a virus all along?

Brain fog and long COVID

Long COVID is described as being a wide range of new, returning, or ongoing health issues after experiencing COVID-19. It is definitely a medical gray area, as many studies are still ongoing, but there are a few things the CDC has been able to pin down:

  • You’ll start to experience the effects of long COVID four weeks after your initial symptoms subside.
  • Long COVID seems to affect those who have contracted COVID-19 more than once or those who have underlying health issues.
  • Symptoms are generally described as tiredness, fatigue, difficulty thinking, headaches, sleep problems, digestive issues, and joint and muscle pain. (But there are many more on that list that you can find here .)

Brain fog is one of the most talked-about symptoms of long COVID, and it’s clear that any lingering inflammation from the illness could be causing it. After all, COVID, like any illness, will trigger your immune system to activate a protective response. However, if you weren’t aware of inflammation symptoms before COVID, you’ll need to determine whether or not they’re related in terms of your own health.

How to tell if your brain fog is related to long COVID

  • Look at the timeline: Pay attention to your body 1-3 months after your initial COVID symptoms subside, noticing anything that doesn’t feel normal for you, like changed sleeping habits, trouble concentrating, and any type of lingering stiffness or pain. This will allow you to catch the patterns that might indicate a deeper issue. In fact, that heightened mindfulness can help you start addressing brain fog and inflammation even if you haven’t recently gone through a bout of COVID.
  • Start a journal: Health journaling is an intuitive process that helps you feel a little more ownership of your body and your symptoms. Tracking your sleep, digestion, hydration, and stress levels is a great way to determine if what you’re feeling is due to external or internal factors. Is it just a bad day or is it part of a larger pattern of body behavior? Even if you don’t feel like something is “serious enough” to write down, taking the time to observe your body objectively can help you start to notice patterns.
  • Talk to your healthcare provider: Advocating for your own health is one of the most important things you can do for yourself. We understand that it can be difficult for women and people of color (and women of color especially) especially to speak openly with their healthcare providers, especially since studies show that fears of being dismissed or ignored are all very much a reality. It can make advocating for something as difficult to describe and as subjective as brain fog all the more daunting. If you struggle to advocate for yourself at the doctor, it may help to write down your questions beforehand and bring someone for emotional support (or to ask the questions for you).

Taking steps to heal brain fog

  • Nutrition: Sometimes, addressing your nutrition can relieve and even heal brain fog. Omegas, B vitamins, and certain antioxidants can be very healing for your brain. Eating foods high in these nutrients is one way to get them in your system. You can also get them through supplements, like Parsley’s Brain Food bundle, designed to boost overall brain health.
  • Hydration: Water accounts for 75% of your brain mass, and each cell requires a delicate balance of water and other elements to function normally. Disrupting that balance can result in brain fog symptoms including impairment to your short-term memory, headaches, fatigue, and stress as the rest of your body tries to adjust to a lack of water. It only takes four hours to become dehydrated, so if you struggle to remember the last time you had a glass of water, set alarms on your phone or carry a bright, colorful water bottle around (maybe even add some fun stickers) to ensure it catches your eye even when you aren’t thinking about it.
  • Sleep: Sometimes better sleep is as simple as limiting the information you feed your brain right before bed—watching the news, for instance, can generate stress and disrupt the vital hormone replenishment that takes place during your REM cycle. And what happens when you can’t get a good night’s sleep? You wake up feeling foggy, groggy, and probably a little inflamed.
  • Stress: Stress is an enormous trigger of chronic inflammation—and it also gets worse with inflammation, which is why stress management is such a key piece of taming inflammation. It's also a major signal of brain fog. Reducing stress with mind-body practices like yoga and meditation can help reduce inflammation and its associated brain fog symptoms.

How Parsley can help with brain fog

Of course, you know your body best. If your brain fog symptoms persist despite the steps you’ve taken, Parsley Health can help. Our holistic approach to medicine will not only help us discover the root cause of your inflammation—it allows our expert doctors to create a personalized health plan to address it and the brain fog it may be causing.

Learn more about how we’ve helped members like you diagnose and treat their brain fog here .

Parsley Health

Parsley Health is the doctor that helps you live healthier, longer, by treating the root cause of symptoms and conditions. Our medical teams—staffed by leading clinicians and health coaches—spend more time with you, order the right tests, and prescribe food, sleep and movement alongside medications so you can get better—and feel better.

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