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concussion brain fog: addressing blood flow, inflammation and gut-brain axis as the underlying issues
brain fog can be a very common symptom that many people experience after a concussion because of various physiological changes that occur in blood flow, inflammation, and hormonal disruptions, to name a few.
5 minute read
if you've experienced brain fog after a concussion, you're not alone. it's a very common symptom caused by inflammation and more.
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brain fog after a concussion is real. you may feel slow. you may lose your place mid-sentence. reading may feel hard. work may take twice as long. post-concussion brain fog has causes that can be addressed. let’s explore why brain fog occurs after a concussion and what you can do about it.
the first reason for brain fog is that it changes blood flow to your brain. right after a concussion, the body’s stress system is activated, constricting vessels, which can impair blood flow to various areas of your brain, negatively impacting the function of cells and brain structures. the result is that you feel foggy and tired faster. research shows that the main way to overcome this is through gentle and consistent exercise. steady state cardiovascular exercise, like stationary bike cycling or running on a treadmill, has the ability to regulate something called the autonomic nervous system, which controls blood flow to your brain. exercise duration and intensity should not exceed the threshold that triggers excessive symptoms, but should gradually challenge your capacity and tolerance.1–4
the second reason is formal changes that can occur within days to months after sustaining a concussion. studies show that a number of hormones that are produced in the brain can either go up or down. the hormones that can be impacted include growth hormone, thyroid-stimulating hormone, and the hormones that regulate the reproductive system, such as testosterone, progesterone and estrogen. a change in one or more of these hormones can impact brain function and stimulate symptoms that can be interpreted as fatigue, poor physical recovery and brain fog. if you’ve noticed that your hormonal systems, like menstrual cycle or energy levels, have changed in the weeks and months after sustaining a concussion, speak to your healthcare provider about getting hormonal testing to assess if this is the cause.5–8
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the third reason that can contribute to brain fog is an increase in inflammation and a disruption in the gut-brain communication system. your gut and brain communicate through multiple pathways all the time. this pivotal information highway is called by researchers the gut-brain axis. one of the main reasons that inflammation is elevated right after a concussion is that the gut lining can become more “leaky” within hours after the injury. in the short term, inflammation can be helpful to promote the repair of tissues, but a problem arises when it becomes chronic and doesn’t resolve. this elevated level of inflammation can stimulate brain fog, low mood, and poor sleep. over time, these imbalances can return to normal, but to speed up the process, following a diet low in ultra-processed foods and high in nutrients can help rebalance these gut changes that influence brain function.9–12
one particular food component that has the potential to impact brain fog the most is the protein called gluten. it is commonly found in wheat and other grain products. many people are familiar with a condition called celiac disease, which is a destructive autoimmune process triggered by gluten. after a concussion, due to some of the changes that occur in the digestive tract, gluten can promote inflammation throughout the whole body, including the brain. research has shown that gluten can loosen tight junctions in the gut lining in some people. that can raise inflammation and may induce symptoms such as brain fog. not everyone needs to avoid gluten forever, but a short trial of 4-6 weeks avoiding all bread and grain products containing gluten can help you determine if it is having an adverse effect on your brain function.13,14
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lastly, sleep plays a major role in brain function and repair. sleep is when the brain does many of its clean-up and repair processes. in recent years, scientists have discovered a specific pathway in the brain called the “glymphatic” system, which helps remove waste. 7-9 hours of deep and restful sleep has a strongly positive impact on daytime focus and memory. unfortunately, many people sustaining a concussion often lose sleep quality and experience changes in sleep patterns. starting with some foundational sleep routine and hygiene changes, such as avoiding screens 1-2 hours before bed, and supplementing with melatonin can be helpful to restore sleep rhythms.15–18
brain fog can be a very common symptom that many people experience after a concussion. we learnt how changes in blood flow, elevated inflammation levels due to a disrupted gut-brain axis, hormonal changes, and poor sleep can all contribute to brain fog. if you or someone you know is experiencing this symptom, share this article with them and always work with your healthcare provider on getting additional guidance on how to recover after a concussion.
dr. paul hrkal bkin nd is a naturopathic doctor, scientific advisor at aqua omega and co-founder at concussion fix.
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references
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