Sunlight and Vitamin D

By Wanda Shimazu Pharm.D.

Essentials for regulation of  immune, respiratory tract and  brain health

Sunlight and Vitamin D;

Essentials for regulation of  immune, respiratory tract and  brain health

Vitamin D (also referred to as “calciferol”) is a fat-soluble vitamin that is naturally present in a few foods and available is a dietary supplement.  Sun exposure causes . Vitamin D production in our skin.  Vitamin D has many roles including bone growth, reduction of inflammation as well as modulation of such processes as cell growth, neuromuscular and immune function, and glucose metabolism.    Many genes encoding proteins that regulate cell proliferation, differentiation, and apoptosis are modulated in part by vitamin D. Many tissues have vitamin D receptors.  During this season of staying indoors and wearing sunscreen whenever we venture out, we may not get the sun exposure that we need. In this article we will focus on two functions of Vitamin D that deserve a deeper look.

Importance to the Immune System

The sun’s ultraviolet radiation causes vitamin D to be produced in the skin.   Our immune systems depend on sufficient vitamin D.  In the winter when sunlight is weaker, vitamin D deficiency is more prevalent.  Influenza is more common in areas where higher latitudes and lower amounts of ultraviolet radiation occur. During the winter solstice and the end of the sunny months, influenza occurrence peaks. 

For each 10 mmol /L increase in the serum vitamin D level, the likelihood of acute lower respiratory tract infection was decreased by half. (Roth).

Vitamin D supplementation is a low-cost, low-risk intervention that providers should consider for children, especially those at high risk for acute lower respiratory infection.  

In developed nations, counted amongst those with insufficient vitamin D are :

  • 40% of pregnant women,
  • Half of all newborns and infants,
  • A high percentage of children and adults .  

Insufficient vitamin D results in infant wheezing and respiratory infections, and children and adults at risk to develop influenza and other respiratory infections.  Middle aged and older adults with low vitamin D levels are significantly more at risk to die from any cause when compared to adults with higher vitamin D levels.

Importance to Cognition and Prevention of Autism

Vitamin D, is essentially a precursor hormone — the building block of a steroid hormone in our bodies called calcitriol. One of the things it does is to help boost the production of glutathione. 

Glutathione is the master antioxidant of all detoxifiers that we make in our bodies.  It is what we need to remove chemicals, metals, toxins, allergens and germs out of our systems. 

Children with autism have a 71-72% decrease in reduced or good glutathione (GSH) and instead their glutathione is oxidized, ie.they have more glutathione disulfide (GSSG).  Other important factors to building glutathione are vitamin B12, , N-acetylcysteine and zinc.

In conclusion, let us consider the greater importance of host immunity verses the common assumption that influenza is caused by different viral strains every year.  Viral strains will not manifest as disease if certain conditions related to strengthening the host immune system are taking place, such as adequate vitamin D levels.   Let us postulate  a new definition of herd immunity, that of including innate immunity which takes place when a percentage of the population achieves vitamin D levels high enough to exert immune pressure on the circulating influenza virus of the season.  

With regard to maintaining good cognition and preventing autism, let us realize that the benefits of sunlight include maintaining and developing our adequate vitamin D stores which leads to our bodies’ glutathione production which is important in detoxifying our neurological systems of metals, chemicals, allergens, germs and other toxins to upregulate and optimize our cognitive systems. 

Suggested prayer:  Lord, we ask for adequate vitamin D levels and nutrition for vital and whole neurologic health, good cognition, and strong immune systems to protect us from any viral or bacterial progression to disease. Help us to enjoy the essential sunlight you have created for us to bring energy and health to our mitochondria and organ systems in our children and grandchildren.  Thank you that we have the privilege of housing the Holy Spirit in our bodies, our temples which we dedicate to You.  You are the light of the world!   In the name of the Lord, Jesus Christ.


Sabetta Jr, DePetrillo P, et al.  Serum 25-hydroxyvitamin D and the incidence of acute viral respiratory tract infections in healthy adults. PLoS One 2010 June 14;5(6):e11088.

Karatekin G, Kaya A, et al.  Association of subclinical vitamin D deficiency in newborns with acute lower respiratory infection and their mothers.  Eur J Clin Nutr 2009 Apr; 63(4):473-77.

McNally JD, Leis K, et al.  Vitamin D deficiency in young children with severe acute lower respiratory infection.  Pediatr Pulmonol 2009 Oct; 44 (10): 981-88.

Larkin A, Lassetter J.  Vitamin D deficiency and acute lower respiratory infections in children younger than 5 years:  identification and treatment.  J Pediatr Health Care 2014 Nov-Dec; 28(6):572-82.

Ginde AA, Mansbach JM, Camargo CA Jr.  Association between serum 25-hydroxyvitamin D level and upper respiratory tract infection in the Third National Health and Nutrition Examination Survey.  Arch Intern Med 2009 Feb 23; 169(4):384-90.

Berger D:  How to prevent autism; expert advice from medical professionals.  Skyhorse Publishing, NY, NY. 2017
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