Vitamin D is made in the skin in response to sunlight, so one question we might ask is whether vitamin D might also somehow promote skin health. One piece of indirect evidence that supports this concept relates to the experience that many sufferers of the skin condition psoriasis have in the sun.

Psoriasis is characterized by raised, red, usually scaly skin “plaques” (often on the knees, elbows, and scalp). Quite often, these can improve considerably and may even disappear when exposed to sunlight.

Psoriasis is thought to be caused by the excessive proliferation of cells in the outer layer of skin known as keratinocytes. Vitamin D regulates a large number of genes in the keratinocytes, which means that vitamin D might have a role to play in the regulation of the division of these cells. Compounds related to vitamin D (vitamin D “analogues,” such as calcipotriol) are sometimes used to treat psoriasis.

I was interested to read a recent study regarding the effect of sunlight on psoriasis. Twenty Swedish men and women (average age 47) were taken for a three-week break in Gran Canaria [1].

The severity of psoriasis in this group was measured using the Psoriasis Area and Severity Index (PASI). Over the course of their time on Gran Canaria, PASI scores declined an average of about 73 percent. There was no control group (a similar group not sunning themselves in Gran Canaria to compare with these results). Nevertheless, these results are impressive and add at least some scientific support for the anecdotal experiences of many psoriasis sufferers.

This study not only looked at individual’s responses to sunlight. The researchers also measured vitamin D levels. At the beginning of the study, the average vitamin D was 57.2 nmol/l (22.9 ng/ml). At the end of the study, levels had risen to an average of 104.5 nmol/l (41.8 ng/ml)?a rise of almost 83 percent.

This study demonstrates that sun exposure really does have the capacity to improve psoriasis. Sufferers will be generally glad of this relief, not only because the condition can be unsightly, but also because it can be uncomfortable. For instance, the plaques can crack and bleed.

The study also shows that sunlight exposure can dramatically enhance vitamin D levels. It should be borne in mind that the study subjects were from Sweden and are likely to have had fair skin because more vitamin D is made in fair skin in response to a given amount of sunlight than in darker skin.

Finally, sunlight appeared to lead to positive changes in the biochemistry of these individuals regarding blood fat and blood sugar levels.

People who go on holiday in sunnier climes very often report feeling better at the end of it. For many, getting away from one’s routine and perhaps hectic, stressful life at home has a part to play. However, it does seem that, through the action of sunlight, one of the reasons that people feel healthier at the end of a holiday is because they are healthier. It seems to me that there really is such a thing as a healthy tan.

Source : www.theepochtimes.com