Vitamin D is broken down into three types: Vitamin D2, which is found in food, Vitamin D3 which is created on the skin, and Vitamin D5, which is the synthetic kind.
Vitamin D3 is basically manufactured by the skin when the skin is exposed to sunlight. The sunlight causes a conversion of the oils on our skin to become a kind of cholesterol. This cholesterol is absorbed into the skin and into our bodies and is known as Vitamin D. Once Vitamin D is absorbed into the body it needs fat to be used by the body. Vitamin D mixes with the healthy fats we eat and the bile from the liver to become used by the body.
Vitamin D is crucial for a healthy immune system, the health of our bones, muscles and joints, and the health of the thyroid. The body is designed to respond quickly to invaders such as bacteria, fungi and parasites. Some of the chemicals that will help in this immune system response are antimicrobial peptides that are found in Vitamin D. These antimicrobial peptides contain such ingredients as cathelicidins.
In the article Ã¬The Epidermal Vitamin D System and Innate Immunity: Some More Light Shed on this Unique Photoendocrine?Ã® in Dermatology 2008;217:7-11 (DOI: 10.1159/000118506) Segaert and Simonart take a look at what advancements are possible with Vitamin D. The nature of the article only speculates what should be looked at in future studies with regard to Vitamin D therapy.
Segaert and Simonart start by explaining the concentration of Vitamin D3 that exists on the skin (Ã¬epidermisÃ®) and the reaction of the sun (Ã¬photosynthesisÃ®) and to create the cholesterol component which becomes Vitamin D (Ã¬7-dehydrocholesterolÃ®).
The article goes on to elaborate on the inconclusiveness of Vitamin D effecting skin conditions from inside of the body, but does elaborate on the noted effects of Vitamin D on psoriasis with the following statement Ã¬production of active vitamin D does not appear to play a major role outside the skin. However, it is tempting to speculate that Ã–D3 may contribute to UVB effects within the skin, such as its therapeutic action on psoriasis.Ã® Although Segaert and Simonart go on to say that any conclusions about the treatment of Vitamin D and psoriasis are inconclusive they state that a pharmeutical product to treat psoriasis should not be out of the question.
Segaert and Simonart go on to speak of the noted effects of Vitamin D on the immune system with statements such as Ã¬vitamin D [is]Ã–directly linked to innate immunity. Therefore, it may explain the increased susceptibility of African-American individuals to tuberculosis and the seasonal peaking of viral infections (influenza) in winter.Ã® Vitamin D is becoming more popular with regard to cold and flu prevention, and other immune system disorders such as food allergies, and over 70 different cancers.
Remember our antimicrobials needed to destroy parasites, according to Segaert and Simonart, individuals that have atopic dermatitis, leg ulcers and thermal burns have low concentration of these antimicrobial peptides, and so the question in the article is can UVB phototherapy be used to stimulate such microbial peptides such as cathelicidins? Segaert and SimonartÃs conclusion? The effects of treating any condition with photosynthesis according to Segaert and Simonart is, Ã¬still poorly understood.Ã®
Segaert and Simonart note that although 25 years have gone by since science first began studying Vitamin D and the connection to the immune system there is now more information on the effects of the microbial peptide cathelicidin, which has Ã¬shown to be increased in human skinÃ–by topical application of active vitamin D.Ã® According to Segaert and Simonart, Ã¬UVB irradiation [a topical application of active Vitamin D] led to elevatedÃ–cathelicidinÃ– is therefore thought by some to underlie the therapeutic effect of phototherapy in lupus vulgaris, for which Finsen received the Nobel prize more than a century ago.Ã® But years later FinsensÃ success with regard to skin tuberculosis was actually attributed to the photodynamic effect of Ã¬ a Mycobacterium tuberculosis porphyrinÃ® Segaert and Simonart go onto to say that science is even more confused because the cathelicidin induced in the skin through UVB irradiation does not even contain Vitamin D.
Confused enough yet?
Segaert and Simonart further speculate the reasons as to why the positive effects of Vitamin D through sunlight exists only in humans and cannot be studied in clinical trials using rodents. Ã¬In contrast to humans and primates, cathelicidin expression is not vitamin-D-regulated in rodents. This is explained by their nocturnal life, which precluded evolution from taking benefit from the biological effects of sunlight.Ã® The reason being, as stated, lies in the nocturnal life of rodents and their inability to draw nutrients from the sunlight. According to Sagaert and Simonart, rodents already posses enough of the cholesterol that converts to Vitamin D so that they are not deprived. Good to know.
Which is probably why a lot of information is not available on the effects of Vitamin D, the clinical trial with rodents is not an option.
According to Segaert and Simonart certain topicals such as Ã¬ketoconazole and itraconazole, which are widely used in dermatology as topical or oral antifungal agentsÃ® may Ã¬interfere with theÃ– antimicrobial peptides in treated patients and hence may alter the Ã–immune system or compromise wound healing.Ã® Conflicting to that information is the statement that the same cathelicidin suppressing and immune suppressing topical ketoconazole might have an Ã¬anti-inflammatory effect in seborrheic dermatitisÃ®. So, what are we to think?
Their one statement on Rosacea which I am sure is why we all want to know what the article is really about is one of many statements that leave me confused, mostly because it seems to be out of context with the entire article. Here is the statement: Ã¬Finally, given the recently acknowledged involvement of cathelicidin in the pathophysiology of Rosacea, the mechanism of action of metronidazole (known to inhibit some cytochrome P450 enzymes) might be reassessed in a similar way as well as the role of sunlight as a rosacea-provoking factor.Ã® Sorry, I wish I knew what they were talking about here.
In conclusion, Segaert and Simonart finds the need for more research with Vitamin D Ã¬not only for the study of anti-infectious immune defense mechanisms but also for a better understanding and treatment of inflammatory skin diseases or compromised wound healing.Ã®
Often in the field of research science and in a scholarly article such as this one, there is a need for speculation. By being able to publish Ã¬the need for research to be doneÃ® in advance of the research being done individuals can increase their funding prospects. If they can determine a need for the research to be done through an article then they are one step closer to a clinical study. So many loopholes.
Personally I think there are other vitamins with a stronger link to the condition of Rosacea such as the essential fatty acidsÃ³both Omega 3 and 6, Vitamin BÃs, Biotin and Amino Acids. I, for one, would like to see more research and a clinical study done on these vitamins.
Thanks for the opportunity,
Nutritionist and MAC Member