Science - and history – show us just how crucial it is for our brains to get enough vitamin D!!

Every day we see more research that points to how brain health can be impacted by not getting enough vitamin D. Yet another recent investigation that examined the relationship between levels of this vital nutrient in stroke patients and the related outcomes found “a novel mechanism underlying the association between vitamin D deficiency and poor stroke outcomes.”

Scientists noted that their study results further emphasize the need to maintain functional vitamin D levels in the management of acute ischemic stroke, which occurs when a blood vessel supplying the brain becomes blocked, as by a clot. In our practice, we generally recommend maintaining levels between 60 and 100 ng/mL in most of patients.
 
Several large observational reviews clearly show how vitamin D deficiency, an unrecognized global epidemic, is associated with increased risks and unfavorable outcomes of a variety of conditions, like cardiovascular andautoimmune disease, some cancers, and neurological disorders.
 
Cumulative evidence indicates that vitamin D can ameliorate neurodegeneration by regulating pertinent molecules and signaling pathways including maintaining Ca2+ homeostasis, reducing oxidative stress, inhibiting inflammation, suppressing the formation and aggregation of the pathogenic protein, and more. 
                                                               
The potentially shrinking brain.
 
It’s not just evidence from modern-day studies that underscores the importance of vitamin D for brain and general health. Several researchers have contended that over time the size of the average human brain has indeed decreased. John Hawks of the University of Wisconsin long held this view, as did Christopher Stringer, a paleoanthropologist at the Natural History Museum, London. And, more recently, Jeremy DeSilva, paleoanthropologist at Dartmouth College, produced a paper after studying 987 skulls that dramatically concluded that the brain size of human ancestors increased 2.1-1.5 million years ago, but started to sharply decrease 3,000 years ago, and is now a lemon smaller. However, it’s important to note that this claim has been refuted by other scientists, notably Brian Villmoare, anthropologist at the University of Nevada, Las Vegas, who contend that the brains examined in DeSilva’s study only represent a small sample in number and years.
 
But, if the human brain is shrinking in size to any degree, then should we consider the role of negative environmental factors? Just some of these impacts include higher Co2 levels, chemicals, toxins, air pollution, the Western diet, GMOs, pesticides, EMFs, stress, lack of adequate sleep, high levels of aluminum from a variety of sources, AND low levels of vitamin D. 
 
There are a number of key points that revolve around the question of brain size changes over the course of history:
 
•Our human brain evolved in a linear fashion up to about 250,000 years ago, when (for reasons that remain a mystery) a sudden, explosive period of growth gave us a neocortex much larger and denser than that of any other species. 
•Technology is evolving, but our brain is not. 
•The human brain evolved when Co2 levels were lower.
•It has been ascertained that the human brain decreased from 1,500 cubic centimeters (cc) to 1,350cc, irrespective of gender and race.
If we continue along this path that impacts the ability to maintain adequate levels of vitamin D, we could end up having the same-sized brain as Homo erectus, an ancient human species which had a brain estimated to measure only 1,100 cc.
 
Brain aging in youth and adults alike.
 
Vitamin D is just one modifiable factor that influences brain health and potentially brain aging. Additional research also underlies the role of vitamin D deficits in accelerated brain aging. In a German population-based cohort study with over 1,800 participants aged 20 to 82, there was a direct correlation between adverse aging in subjects whose vitamin D levels were lacking. While this was primarily significant in older populations, the association in younger subjects was still relevant. Researchers noted that “in summary, our results support previous findings suggesting that vitamin D-deficient individuals have advanced brain aging.”
 
There are additional concerns particularly in our youth populations that arose in recent years and included:
•As a result of social isolation and distancing during the shut-down, virtually all youth experienced adversity in the form of significant departures from their normal routines. In addition, financial strain, threats to physical health, and exposure to increased familial violence were alarmingly common during the pandemic.
•A small study comparing brain scans of young people from before and after 2020 reveals that the brains of teens who lived through the pandemic look about three years older than expected
•Compared to carefully matched peers assessed before the pandemic, adolescents assessed during the pandemic showed signs of advanced cortical thinning and had larger bilateral hippocampal and amygdala volumes.
 
Vitamin D deficiency is a universal problem.
 
One issue that particularly affects our ability to naturally maintain healthy levels of vitamin D is an emphasis on indoor lifestyles, about which we have previously written at length. A reliance on technology devices and entertainment that takes place in front of televisions instead of in backyards or at playgrounds has truly put our children at risk of deficiencies that are not always identified. Less exposure to sunlight through outdoor play and/or poor-quality diets, even in countries with ample food sources, make it more important to consider supplements. But that’s often a problem in parts of the world where access is limited or nonexistent.
 
Vitamin D is a fat-soluble vitamin that depends on the gut's ability to absorb dietary fat. People who are obese tend to have lower blood vitamin D levels. And while Vitamin D accumulates in excess fat tissues, it is not easily available for use by the body when needed. Additional environmental factors, even the latitude at which we live along with air pollution, can also affect vitamin D synthesis. 
 
Patients with conditions including neurological and neuroautoimmune disorders are advised to obtain measurements of their vitamin D levels and based on individual health needs, consider the value of adding a high-quality vitamin D3 supplement. But always talk to your physician before adding or changing your current regimen. 
 
Most importantly, you and your family should try to spend some time outdoors every day. There are so many benefitseven beyond the power of sunlight that come from getting out in nature. Your brain and your body will thank you!
 
In hope and healing,
Dr. Suzanne Gazda
 
Additional reading:
 
Gazda, S. More studies point to critical importance of vitamin D in immune health. 2020.
https://www.suzannegazdamd.com/blog/more-studies-point-to-critical-importance-of-vitamin-d-in-immune-health
 
Gazda, S. The indoor generation is missing out on vitamin D. 2021.
https://www.suzannegazdamd.com/blog/the-indoor-generation-is-missing-out-on-vitamin-d
 
References:
 
Cui, P. et al. Microglia/macrophages require vitamin D signaling to restrain neuroinflammation and brain injury in a murine ischemic stroke model. J of Neuroinflammation. March 2023.
https://jneuroinflammation.biomedcentral.com/articles/10.1186/s12974-023-02705-0
 
Menon V, Kar SK, Suthar N, Nebhinani N. Vitamin D and Depression: A Critical Appraisal of the Evidence and Future Directions. Indian J Psychol Med. 2020;42(1):11-21. Published 2020 Jan 6. doi:10.4103/IJPSYM.IJPSYM_160_19.
 
Schmerling, R. Can vitamin D supplements prevent autoimmune disease? Harvard Health Publishing. 2022.
https://www.health.harvard.edu/blog/can-vitamin-d-supplements-prevent-autoimmune-disease-202203242712  
 
Wang W, Li Y, Meng X. Vitamin D and neurodegenerative diseases. Heliyon. 2023;9(1):e12877. Published 2023 Jan 12. doi:10.1016/j.heliyon.2023.e12877
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9938420/
 
 
Cannon JR, Greenamyre JT. The role of environmental exposures in neurodegeneration and neurodegenerative diseases. Toxicol Sci. 2011;124(2):225-250. doi:10.1093/toxsci/kfr239
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3216414/
 
Beyond Pesticides, Daily News Blog. Retrieved March 2023.
https://beyondpesticides.org/dailynewsblog/2022/08/new-evidence-shows-roundup-damages-the-nervous-system/
 
Duhani, I. The effects of electromagnetic fields on human health. Physica Medica. 2016.
 
Liu, C. et al. Increasing breadth of the frontal lobe but decreasing height of the human brain between two Chinese samples from a Neolithic site and from living humans.” American Journal of Physical Anthropology. 2014.
 
Kisielinkski, K. et al. Possible toxicity of chronic carbon dioxide exposure associated with face mask use, particularly in pregnant women, children and adolescents – A scoping review. Heliyon. March 2023. 
 
Allen, J. et al. Associations of Cognitive Function Scores with Carbon Dioxide, Ventilation, and Volatile Organic Compound Exposures in Office Workers: A Controlled Exposure Study of Green and Conventional Office Environments. Env Health Perspective. 2016