Seeing through the Clouds: Brain Fog in Parkinson’s

Many individuals with Parkinson's disease (PD) have experienced a struggle to think clearly or a sensation of mental fuzziness. This frustrating non-motor symptom is aptly named “brain fog,” as it suggests a fog or cloud obscuring clear thinking. People with brain fog may have trouble focusing, remembering things, or finding the right words to say. Ultimately, this can result in not feeling like yourself (Lee, n.d.). Brain fog can arise from many factors, including fatigue, medications, and lifestyle choices (Daniels, 2020).

In particular, fatigue is a major contributor to feelings of brain fog. It is no surprise to many that Parkinson’s disease, especially its motor symptoms, can cause sleeplessness. Issues such as insomnia and excessive daytime sleepiness can also be symptoms of Parkinson’s itself, because the disease affects the brain's ability to regulate sleep (Daniels, 2020). However, what is lesser known is that side effects from common antiparkinsonian medications can also cause fatigue. Some people report feelings of tiredness shortly after taking levodopa or certain dopamine agonists (in particular, pramipexole and ropinirole) (Hobson et al., 2002). A lack of sleep disturbs the communication between our brain cells, resulting in momentary lapses in mental function that impact memory and visual perception (Schneiderman, 2018).

Whatever the cause of fatigue, managing it is an important step in overcoming brain fog. One way people with PD can ensure a better night’s sleep is to take over-the-counter melatonin supplements. In fact, studies have found that people with Parkinson’s have lower levels of melatonin secretion when compared to the general population. For those who do not wish to take or cannot tolerate melatonin, there are other medication treatment options, including the antidepressant mirtazapine, which may also be beneficial in treating tremor (Daniels, 2020). Speak with your doctor about what is right for you. Additionally, ensuring good sleep hygiene practices can make a big difference in promoting restful sleep. These include no screens one hour before bed, ensuring your sleeping place is both dark and cool, and avoiding caffeine at least eight hours before bed. You may also wish to avoid daytime napping, as it can disrupt night sleep (Lee, n.d.).

Another powerful tool against brain fog is the power of moderate- to high-intensity exercise. Researchers at the University of British Columbia looked at what happened to nearly 100 women in their 70s and 80s as a result of an aerobic training program. When compared to those who participated in balance and muscle toning exercises, the aerobic group showed substantial growth in a part of the brain called the hippocampus after six months, which is responsible for learning, memory, and emotion (ten Brinke et al., 2015).

This finding is significant, especially since after the age of 20, the hippocampus declines by 1% each year in most people. In addition to its brain-boosting effects, exercise gets the blood pumping and adrenaline flowing, which can enhance memory and feelings of being energized – the exact opposite of the sluggishness associated with brain fog (University of Central Florida, n.d.).

Another important thing to consider is diet, which can play a significant role in brain fog. In particular, a vitamin B12 deficiency can cause several cognitive issues, as this vitamin supports a healthy brain and nervous system. It is primarily found in animal products, such as meat, eggs, and dairy, which is why those eating vegetarian and vegan diets must take care to supplement their intake – doctors recommend adults take 2.4 micrograms of B12 every day (Daugherty, 2024). Seniors and older adults also absorb less vitamin B12 from their diet, resulting in up to 38% of older individuals having mild B12 deficiency (Stover, 2010). And one study of people with Parkinson’s disease found that those who had lower B12 levels had faster-advancing cognitive and motor symptoms from the illness (Leigh, 2018). Fortunately, checking vitamin B12 levels is done with a straightforward blood test, so speak with your doctor.

Additionally, a diet high in refined sugar has been found to be harmful to brain function by causing inflammation and oxidative stress (Selhub, 2022). Diets high in fat and sugar, even for a short period time, can lead to problems with memory and learning because of changes observed in the hippocampus. Specifically, these diets can cause the branches of brain cells to shrink, spaces between cells to widen, and the area where cells receive signals to narrow. All of these changes affect how well the brain can adapt (called neuroplasticity), which is important for optimal brain health and learning (Fadó, 2022).

Harvard nutritionist Dr. Uma Naidoo recommends everyone eat a diverse, whole food diet as much as possible to stave off brain fog. She recommends eating foods with multiple colours, choosing foods with high micronutrient content (such as B vitamins, calcium, magnesium, and iron), consuming healthy fats (such as avocado oil, which is anti-inflammatory), and staying away from anything that will cause big spikes in blood sugar – what goes up must come down, resulting in energy crashes and cloudy thinking (Naidoo, 2023).

Finally, the key role that hydration plays in brain fog cannot be overlooked. Losing as little as two percent of the water in your body can reduce cognitive abilities, attentiveness, memory, and your ability to make decisions (BBC, n.d.). People with Parkinson’s disease are particularly at risk for dehydration because PD itself can reduce feelings of thirst or cause issues with swallowing, which can make some individuals fearful of choking. Additionally, symptoms of autonomic dysfunction in Parkinson’s, such as excessive sweating, drooling, and increased urination, contribute to greater water loss. In some cases, nausea and diarrhea may be side effects of some antiparkinsonian medications, further leading to dehydration. Because of these challenges, people with Parkinson's typically consume an average of 30% less fluids than those without the disease (Parkinson's Disease Research, Education, and Clinical Centers, 2007). Setting alarms to drink water may be one strategy to get enough liquids, as well as flavouring the water to improve its taste, adding thickening agents to liquids to make them safer to swallow, or eating plenty of water-rich fruits and vegetables, such as watermelon (Parkinson's Disease Research, Education, and Clinical Centers, 2007). However you choose to get your six to eight glasses a day, keep in mind that each sip leads to better brain function.

Managing brain fog in Parkinson’s disease involves a multifaceted approach; from addressing fatigue through sleep management and medication adjustments to embracing the benefits of exercise, diet, and hydration, individuals can take proactive steps towards mental clarity. With an approach tailored to individual needs and guided by medical advice, people with PD can strive for clearer thinking, enhanced memory, and improved quality of life in their Parkinson’s journey.

Sources

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Daugherty, L. (2024). These Key Vitamins Can Help Combat Brain Fog. https://www.cnet.com/health/nutrition/key-vitamins-to-combat-brain-fog

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Hobson, D. E., Lang, A. E., Martin, W. R. W., Razmy, A., Rivest, J., & Fleming, J. (2002, January 23/30). Excessive Daytime Sleepiness and Sudden-Onset Sleep in Parkinson Disease: A Survey by the Canadian Movement Disorders Group. JAMA, 287(4), 455-463. doi:10.1001/jama.287.4.455

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Naidoo, U. (2023). Harvard nutritionist lives by these 6 rules to keep her brain sharp and happy. https://www.cnbc.com/2023/12/26/harvard-nutritionist-ive-always-lived-by-these-6-food-rules-for-a-stronger-happier-brain.html

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Schneiderman, M. (2018). Why You Have a ‘Foggy Brain’ If You Don’t Get Enough Sleep. https://www.healthline.com/health-news/foggy-brain-lack-of-sleep

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ten Brinke, L. F., Bolandzadeh, N., Nagamatsu, L. S., Hsu, C. L., Davis, J. C., Miran-Khan, K., & Liu-Ambrose, T. (2015). Aerobic Exercise Increases Hippocampal Volume in Older Women with Probable Mild Cognitive Impairment: A 6-Month Randomized Controlled Trial. British Journal of Sports Medicine, 49(4), 248–254. doi: 10.1136/bjsports-2013-093184

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This content was published in the Summer 2024 edition of our quarterly magazine, Viewpoints. The content was accurate as of this publication date.