Best Treatment for COVID Brain Fog

Estimated reading time: 20 minutes

Some new research has come out evaluating the occurrence of neurological symptoms in people who were infected with COVID. They found that in those infected with COVID (the original, not the variants), there was a 42% increased chance of developing neurological issues.

And one of those identified is brain fog. And some of you are suffering from brain fog that you suspect comes from past COVID infection (variant or not). And you are wondering what you can do about it, how you can decrease your brain fog symptoms, and facilitate healing.

If you have been suffering from recurrent or persistent brain fog since your Covid infection, I want you to know you are not alone.

A lack of cognitive acuity has increasingly been described in the literature as “brain fog” … Although there is not yet consensus on how to define this term, memory loss, poor focus, reduced concentration, increased word-finding latency, difficulty tracking complex information, and decreased executive functions have all been associated with the term. 

Rivas-Vazquez, R. A., Rey, G., Quintana, A., & Rivas-Vazquez, A. A. (2022). Assessment and Management of Long COVID. Journal of Health Service Psychology, 48(1), 21-30. https://link.springer.com/article/10.1007/s42843-022-00055-8

And because I am all about you knowing all of the ways you can feel better, I will devote this post to showing you why a ketogenic diet is an evidence-based first step in providing a powerful treatment for your COVID-related brain fog symptoms.

The studies I looked at (see references at end of article) discussed that most of the data came from people over 60 and that those hospitalized generally had more severe neurological problems after. But as someone who helps people with their brains and is active in various forums, I can assure you that plenty of post-COVID brain fog is experienced in all age groups. And that is what they are finding in these papers evaluating the numbers. Even people with mild infections can go on to develop neurological problems. No hospitalization experience indicative of severity seems to be required.

The most frequent neurological manifestations of ‘long-COVID’ encompass fatigue; ‘brain fog’; headache; cognitive impairment; sleep, mood, smell, or taste disorders; myalgias; sensorimotor deficits; and dysautonomia. 

The most frequent neurological manifestations of ‘long-COVID’ encompass fatigue; ‘brain fog’; headache; cognitive impairment; sleep, mood, smell, or taste disorders; myalgias; sensorimotor deficits; and dysautonomia. 
https://doi.org/10.1177/20406223221076890

And for those suffering, it is a scary and debilitating experience, with minimal support available in the form of prescriptions or medical treatments to alleviate symptoms.

And while that may change in the future, many of you are suffering now. And I want you to know that effective treatments exist using metabolic brain therapies like the ketogenic diet.

What kinds of neurological problems do we see with long COVID that are directly relevant to brain fog or that we often find co-occurring with brain fog symptoms?

• Cognition and memory disorders
• Episodic headaches and even migraines
• Mental health – stress and adjustment disorders, anxiety disorders, major depressive disorder, and psychotic disorders

So how would a ketogenic diet assist with these serious neurological issues brought on by Covid infection?

Ketogenic diets allow the body to produce ketones. And ketones are molecular signaling bodies that influence gene expression. And the gene expression it provides can improve the expression of brain energy in hypometabolic (low energy use) structures, reduce neuroinflammation and oxidative stress, and improve neurotransmitter balance.

What do these things have to do with long Covid? Everything. We see problems with these four factors in long Covid, and particularly with neurological symptoms that manifest as a result of prior Covid infection.

Let’s explore the literature.

Brain Hypometabolism and Covid Brain Fog

Areas of brain hypometabolism occur and can persist after Covid infection. Hypometabolism is a term used to describe an inability or impaired ability to produce energy (hypo=low, metabolism=energy creation). Individuals suffering from long Covid symptoms have been seen to have persistent areas of hypometabolism in the frontoparietal and temporal lobes, which was seen to be improved after 6 months from the onset of symptoms.

Which is good. It’s great that the hypometabolism seen post-Covid is thought to be eventually resolved. But here is the thing. A bout of long-term brain hypometabolism is a disaster. While your brain struggles to use energy in those areas, oxidative stress goes up, and if severe enough, structures will shrink. There is a risk of losing grey matter (brain). It is not in your best interest to “wait it out” for those brain parts to turn back on and be able to use energy well again. You need to rescue brain energy NOW!

Further consistent changes included functional and structural abnormalities in the insula and parahippocampus.

Najt, P., Richards, H. L., & Fortune, D. G. (2021). Brain imaging in patients with COVID-19: A systematic review. Brain, behavior, & immunity-health, 16, 100290.

This is a problem. While the most persistent changes were seen in the olfactory areas of the brain, we cannot ignore the persistent changes seen in the insula and the parahippocampus. Both are important structures in cognition and memory.

An additional area of more persistent hypometabolism is the fronto-insular cortex. This area of the brain consists of important networks of connections that are integral to cognitive control ability. This looks like the ability to switch attention, hold attention, bring attention back to a task, and generally be able to focus. These are complaints we hear people with long-COVID brain fog complain of regularly. And therefore, I would suggest that the brain hypometabolism that is experienced should be a primary point of intervention.

There is a crisis in brain energy after a Covid infection. It is well documented that SARS-COV2 induces mitochondrial dysfunction and underlies the persistent neuropathology seen in some people with long-Covid symptoms.

What do mitochondria do?

Luckily, science has an intervention that rescues brain energy. Both by providing an alternative fuel source and improving mitochondrial number and function.

Ketogenic diets for brain hypometabolism and mitochondrial dysfunction seen in Covid brain fog

Ketogenic diets are used specifically to improve brain hypometabolism in various populations. The most common use is with Alzheimer’s disease, in which important brain structures can no longer utilize glucose for fuel effectively. This causes areas of the brain to starve literally and increases oxidative stress, which causes further deterioration. How do ketogenic diets rescue brain energy? By providing an alternative fuel source. Ketogenic diets produce ketones, which are a preferred fuel source for the brain. They can bypass broken machinery needed to shuttle glucose in and are directly absorbed into the cell and used by cell batteries (mitochondria), a superior fuel source.

I don’t call them a superior fuel source lightly. Because ketones are not only a fuel source, they are molecular signaling bodies that have powerful, multi-faceted effects to promote brain energy. Ketones will effect changes that will increase the number, health, and efficiency of existing mitochondria (aka cell powerhouses) providing energy.

So just like in people with mild to moderate Alzheimer’s disease, ketogenic diets can rescue areas of brain hypometabolism and increase brain energy through improved mitochondrial function. And there is absolutely no reason to believe that they would not accomplish the same service for areas of brain hypometabolism due to Covid. Nor is there a reason to believe that a ketogenic diet would be unable to ameliorate the mitochondrial dysfunction well-documented in the scientific literature attributed to Covid. In fact, without improved brain energy, those cells cannot do the work to repair those structures and rebuild.

The decrease in brain energy that comes from poor mitochondrial function and areas of brain hypometabolism cause a ton of oxidative stress. So it doesn’t surprise me that oxidative stress is also consistently seen to be a problem with long-Covid.

This brings us to our next section.

Oxidative Stress and Covid brain fog

There is simply no question or debate about whether we see oxidative stress in long-Covid patients.

neuroinflammatory and oxidative stress processes are thought to prevail in propagating neurological ‘long-COVID’ sequelae

Stefanou, M. I., Palaiodimou, L., Bakola, E., Smyrnis, N., Papadopoulou, M., Paraskevas, G. P., … & Tsivgoulis, G. (2022). Neurological manifestations of long-COVID syndrome: A narrative review. Therapeutic advances in chronic disease, 13, 20406223221076890.

Oxidative stress is the term used to describe an imbalance between the amount of damage going on in a cell and the body’s ability to combat it and be able to keep up with repairs. It is thought that oxidative stress may be responsible for the endothelial and vascular dysfunction we see occur after infection up to 4 months after (and many of you will have experienced this even longer). Oxidative stress is like a clean-up crew that is too few in number and not enough cleaning supplies to go around. They can’t do the work. And your brain doesn’t repair. And this causes a cycle of additional damage that cannot be repaired. And I think you get the idea.

Addressing the oxidative stress that is part of long-Covid brain fog needs to be a primary area of focus.

Oxidative stress in Covid brain fog and ketogenic diets

So how does a ketogenic diet help reduce oxidative stress? A lot of ways. Burning ketones for fuel provides cleaner energy with fewer byproducts to clean up. But mostly, I think the sweet spot is in its ability to upregulate the production of endogenous antioxidant systems. In particular, the production of more glutathione.

Glutathione and the ketogenic diet

Glutathione production is crucial. And the signaling molecule properties of ketones help your body make more of it. And if you have brain fog symptoms, regardless of reason, glutathione is really your best friend and cooperative component in your recovery.

If you have long-Covid that has manifested as brain fog symptoms, it is likely you have developed a leaky blood-brain barrier. That means things are getting close to your brain that are not supposed to be up in there, causing your brain’s immune system to freak out and contribute to neuroinflammation through the production of inflammatory cytokines.

You were supposed to have a healthy blood-brain barrier to keep them out. But your Covid infection may have made that not possible, and it could still be desperately trying to repair (but lacking brain energy, sufficient micronutrients, and a nonstop oxidative stress assault, simply cannot).

Luckily, ketogenic diets are great for blood-brain barrier integrity. I wrote about it here in this article below:

Leaky Brain and Ketogenic Diets

Glutathione is used to help repair this barrier, and it is also used to help repair the damage. And I just cannot think of a scenario in which the upregulation in the production of glutathione would not be of astronomical importance and benefit for someone struggling with long-Covid brain fog symptoms.

Neuroinflammation and Covid Brain Fog

You don’t have to contract Covid to know how inflammatory cytokines feel in your brain. Anyone who has come down with a particularly bad cold or even the flu knows how tired you get. You just sit or lie down, and you pretty much do not get up again until you are feeling better. Your brain doesn’t work well, and you don’t dare go near anything in which accuracy or focus is required. And quite frankly, you don’t have the motivation to even try! You turn on your favorite movie and nap with your cat until you feel better (Ok, that’s me, but you probably do something similar). These are sickness behaviors initiated by inflammatory cytokines in your brain.

Inflammatory cytokines in the brain are a necessary part of recovery. But there are definitely conditions where an inflammatory process gets started and cannot calm itself down and just continues out of control. Traumatic Brain Injury (TBI) is a great example of this, as are certain infections. This can also happen if your immune system is not balanced and working well.

So if you tell me that you are still experiencing sickness behaviors post-Covid infection, I believe you.

And so does the research literature.

The inflammatory cytokine storm we have all heard about increases neuroinflammation, which then in turn produces enormous oxidative stress. Remember, after inflammation there needs to be a clean-up crew. This leads to a widespread neuroinflammatory process.

And many people who endured a Covid infection were coming into it already with untreated neuroinflammation due to lifestyle disease, poor or insufficient nutrient status, or some other disadvantage that would make it difficult to calm the neuroinflammatory process back down.

You didn’t need to have a “storm” to create a neuroinflammatory process that is having trouble calming back down on its own. Plenty of people with cases considered to be of mild Covid are suffering from brain fog.

So you need a powerful intervention to reduce inflammation. And the most powerful intervention to reduce inflammation (and neuroinflammation in particular) that I know is the ketogenic diet. Let me tell you how it works.

Ketogenic diets and Covid brain fog neuroinflammation

Ketogenic diets create ketone bodies. One of those ketone bodies is called beta-hydroxybutyrate (BHB). BHB is a molecular signaling molecule, and this means that it is powerful enough to turn gene expression off and on. One of the magical properties of BHB is its ability to turn down chronic inflammatory gene expression. You still get a well-functioning acute inflammatory response, like you would need if you hit your shin on the bed frame or cut yourself while preparing dinner. But it shuts down and dampens the genes that turn on and facilitate and maintain a chronic inflammatory response.

And if you are dealing the brain fog post-Covid, you really need that.

Best treatment for brain fog and neuroinflammation

Neurotransmitter Imbalance and Covid

Normally, when I write about ketogenic diets and neurotransmitter balance, I write about their effects on serotonin, dopamine, norepinephrine, GABA, and glutamate. There are really a lot of blog posts on this site about the effects of those neurotransmitters. You can do a search on any of them on the search bar at the very bottom of this article and learn more!

But because this post is about Covid specifically, we will dive more into Nitric Oxide (NO), which can be conceptualized as a retrograde neurotransmitter.

Nitric Oxide (NO) and the associated enzyme that produces it (Nitric Oxide Synthase) are super important and do so many things that are important to help regulate the very symptoms that people with long-Covid often complain about. It helps regulate pain, neuroendocrine function, and the HHP Axis (hypothalamus-hypophysis axis) that regulates stress response, immune system, mood, sleep, and hippocampal (memory) function.

And perhaps most striking and potentially relevant is that Nitric Oxide (NO) impairs platelet aggregation. Platelet aggregation is the process by which platelets stick to one another at sites of vascular injury.

This could be helpful when we talk about reducing the incidence of stroke.

In fact, after an acute Covid infection, your body tries to produce more nitric oxide to help heal the damage.

Following SARS-CoV-2 infection, blood-borne competent mitochondria provide a novel source of restorative ATP and constitutive nitric oxide synthase (cNOS) to stimulate the release of nitric oxide (NO), which is anti-inflammatory

Stefano, G. B., Büttiker, P., Weissenberger, S., Martin, A., Ptacek, R., & Kream, R. M. (2021). The pathogenesis of long-term neuropsychiatric COVID-19 and the role of microglia, mitochondria, and persistent neuroinflammation: a hypothesis. Medical Science Monitor: International Medical Journal of Experimental and Clinical Research, 27, e933015-1.

…we propose that some of the neurological signs in patients with COVID‐19 are associated with the virus‐induced decrease in NO levels in the brain. 

Annweiler, C., Bourgeais, A., Faucon, E., Cao, Z., Wu, Y., & Sabatier, J. M. (2020). Neurological, Cognitive, and Behavioral Disorders during COVID‐19: The Nitric Oxide Track. Journal of the American Geriatrics Society. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7361837/

Wouldn’t it be great if there was a way to enhance your production of nitric oxide so you could help heal your brain?

Exercise increases nitric oxide, but I know some of you are suffering from exercise intolerance either due to chronic fatigue that has developed or you get shortness of breath easily as part of your long-Covid symptoms. So I will not tell you just to get out there and exercise because some of you can’t.

Luckily, there is another powerful way to increase Nitric Oxide (NO) production. You guessed it. It’s the ketogenic diet!

Ketogenic diets and neurotransmitter balance – effects on Nitric Oxide and likely treatment for Covid brain fog

Ketogenic diets enhance neurovascular function, particularly by facilitating increased Nitric Oxide (NO) production. In fact, researchers talk about how implementing a ketogenic diet early in cognitive decline can reduce the risk of Alzheimer’s disease, in part because of the pronounced enhanced brain vascular function that is observed. And there is also research to suggest that the ketogenic diet specifically increases NO production in important structures needed for memory, like the hippocampus. And I don’t know anyone who complains of brain fog that does not also complain to some degree about decreased memory function.

But my symptoms are mostly anxiety and depression!

That’s ok. A healthy brain is a healthy brain. If you believe your brain fog symptoms coming from long Covid are mostly due to a mood disorder that came on as a result, a ketogenic diet will still be a powerful treatment for the underlying mechanisms involved.

You can learn more about how a ketogenic diet can be a primary treatment for mood disorders like anxiety and depression. You may want to begin by exploring these articles below:

Can keto treat my depression without medication?

How do ketogenic diets help anxiety disorders?

But what about my cardiovascular health?!

If you are fearful of using a ketogenic diet because you are afraid of saturated fat, I really need you to get over that. It’s not considered an evidenced-based stance. Nobody who has been keeping up with the research on this topic believes that anymore. And the failure of that information to disseminate down to the public is getting in the way of people using powerful evidence-based therapies like the ketogenic diet to heal chronic diseases.

Don’t take my word for it. I am just a licensed mental health therapist with additional training in using metabolic, nutritional, and functional psychiatry methods. I am not a cardiologist or anything.

But these people are:

They did a review of the scientific literature, and they concluded the following:

So if you are suffering from recurrent and chronic brain fog because of Covid, please consider a ketogenic diet. And don’t let unsubstantiated and poorly researched fear-mongering get in your way.

Conclusion

Here is the thing. If you are post-Covid and still suffering from brain fog, whether it’s a month later or even years later, I’m not sure your doctor or neurologist is up to being able to help you treat it. If they were, you wouldn’t be here reading this article. And you cannot wait around for them to catch up on what effective root-cause treatments are going to help. Doctors and neurologists specifically are steeped in pharma as the primary, and quite frankly, only, intervention for what you are experiencing.

But we don’t have a pill that fixes brain hypometabolism, oxidative stress, and neuroinflammation. And while pharma would attempt to argue that there are prescriptions for neurotransmitter imbalances, those medications do not and will not address brain hypometabolism, oxidative stress, and chronic neuroinflammation.

Pharma has attempted prescriptions to fix these things without success. And that does not surprise me. You are a complicated and beautiful system. You deserve a balanced and pleiotropic intervention. Which is exactly what a ketogenic diet is. And a ketogenic diet is available to you right now.

Ketogenic diets, and the ketones they produce, have additional benefits for people suffering from long-Covid that are beyond the scope of this article. They include powerful immune system balancing effects, positive microbiome changes, and even improved blood-brain barrier repair and function.

Leaky Brain and Ketogenic Diets

Ketogenic Diets and Gut Microbiome

It’s time to take your neuro-cognitive functioning back and use a powerful, evidence-based intervention for the underlying mechanisms of pathology we see going on in long-Covid brain fog.

You can absolutely learn how to do a ketogenic diet to treat mood and cognitive problems with resources here on this blog! This post below is a wonderful place to start.

Keto diet rules for mental health

If you would like help moving towards a ketogenic diet and would like to implement additional powerful nutritional therapies as part of your recovery, I encourage you to check out my Brain Fog Recovery Program. It has been my joy and pleasure to help many people suffering from long-Covid “get their brain back” so they can live their best life and thrive!

Brain Fog Recovery Program

But most importantly, I just really want you to know that evidence-based treatment for impaired neurocognitive function, even after a virus like Covid, absolutely exist. And that if your doctor doesn’t know enough about them to suggest them to you, that doesn’t mean you have to continue to suffer while they catch up to the literature. I want you to know all the ways you can feel better. And this is one of them.

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