As professors of dermatology and skin scientists, we want to provide the public with reliable, up to date and scientifically sound information about our skin and how it functions to keep us well.
Just as there is more to owning and operating a car then simply filling the gas tank and turning on the ignition, so, too, taking a closer look at how the skin operates will make us better stewards of its health and beauty. We offer both in-depth articles based upon the latest scientific understanding and research and shorter answers to commonly asked questions.
We welcome your comments and suggestions.
How is Pigmented Skin More Acidic?
As we discussed in an earlier post, darkly pigmented skin is superior to lightly pigmented skin. It functions better in holding in body water. It does a better job of preventing skin infections. And it is better at resisting mechanical trauma. We then discussed work from the Elias laboratory demonstrating that this superiority is due to the lower pH of the skin surface. In other words, darkly pigmented skin is more acidic. Yet darkly pigmented skin has the same number of pigment-forming cells (‘melanocytes’) as does lightly colored skin. So, what then is the difference in the melanocytes of darkly- vs. lightly-pigmented skin? Well, one big difference is in the the clusters of pigment (or ‘melanin granules’) made by melanocytes in darkly pigmented skin. They are larger and more numerous than the sparser and smaller melanin granules made by pale skin. Melanocytes transfer these granules to the cytoplasm of neighboring epidermal cells (‘keratinocytes’) using their long arms (or ‘dendrites’). This transfer process happens in both light and dark skin, but here’s where things proceed differently.
The small, crumbly (read ‘crummy’, if you wish) pigment granules of very lightly pigmented skin are degraded within the keratinocytes well before they can reach the outermost layers of the epidermis. In contrast, the larger, more robust melanin granules of darkly-pigmented skin persist within cells as they mature and move outward towards the skin surface. [Continue Reading…]
INSIDE THE SKIN BARRIER
This proposition - that black skin is better skin - is not a political statement. Rather, it is based upon scientific observations. Darkly pigmented skin is functionally superior to lighter colored skin in several ways. Our purpose here is give our readers a scientific perspective to a socially … [Read More...]
This is the 4th in our series of updates on atopic dermatitis. In the preceding articles we considered why so many more children nowadays are developing eczema, what we know about the genetic underpinings of the disease, and how defects in the skin barrier and loss of the acidic pH on the skin … [Read More...]
Q & A
Pores on the skin represent openings of hair follicles and sweat ducts. These pores do not ‘breathe’ in the usual sense – our lungs take care of that need. Yet, it can help to keep your pores open. Sweat gland openings can become obstructed – for example, by wearing skin tight clothing … [Read More...]
REPAIRING THE SKIN BARRIER
Know anyone with psoriasis or some type of eczema? Most of us do. These are common skin conditions: one child in five has atopic dermatitis; 2% of the population has psoriasis. That’s a lot of people! Treatment is an ongoing battle for many who are affected by one of these conditions. They must … [Read More...]