The most common response from my patients, when asked about what agents they use to moisturize their legs and feet is: Vaseline. It is a complete myth that Vaseline moisturizes skin, but it does a very good job at creating that façade!
The skin is composed of three main layers: the epidermis, dermis and subcuticular layers.
Epidermis: the upper/outermost layer of skin, which is obviously the most visible layer and itself has 5 distinct layers. It acts as the initial barrier to protect the body from invasion by bacteria and other foreign materials and substances. Its main cellular component is called a “keratinocyte,” which makes its way from the lowest layer of the epidermis to the top layer of the epidermis. By the time keratinocytes reach the top layer of the epidermis, a.k.a. the surface of the skin, these cells are dead and thus, dry skin!!
Dermis: the second layer of skin, that is not visible to the eye, and is made of up two distinct layers. The dermis plays a very important role in the formation of hair follicles and sweat glands, helping to regulate the temperature of the skin and body. It also contains blood vessels that supply the skin.
Subcuticular: the deepest of the three layers that make up the skin. It consists mainly of fat cells that store energy, varying in thickness depending on what area of the body the skin is covering.
The skin has a very distinct cycle of growth, development and death (dry skin). The keratinocytes (principle cells in the epidermis) take 8-10 weeks to rise from the bottom of the epidermal layer to the top of the epidermal layer. As I mentioned before, once they reach the top layer, they are no longer “living cells” and appear as dry skin. To keep the skin healthy, this top layer of non-living Keratinocytes needs to be removed, and moisture put in its place. Vaseline neither removes non-living keratinocytes nor imparts moisture into the skin. Therefore, it is not a good option for “moisturizing,” but because it seals in any moisture that might already be present in the skin, it does a very good job at ‘pretending’ to moisturize!
So what is a good option for moisturizing the skin? The answer: it depends on the condition of the skin. For mild conditions, imparting moisture into the skin may provide adequate results, but in more severe conditions of dry skin, keratinocytes need to be removed so that the moisturizing agents can reach healthier layers of the skin. Therefore combinations of desquamation agents (used to remove keratinocytes) and moisturizing agents are best!
In a patient with mildly dry skin, moisturizers alone (substances that impart moisture into the skin), can work fairly well and can be found over the counter at your local drug store. Some good options include: CeraVe, Eucerin and Vaseline Intensive Care.
In a patient with mild to moderately dry skin, there are prescription lotions that will help remove some of the keratinocytes on the surface of the skin as well as impart moisture. These agents usually contain an ingredient called Lactic Acid. A commonly prescribed lotion for mild to moderately dry skin is called AmLactin.
For patients who have severely dry skin, prescription strength lotions can be given to remove most of the keratinocytes on the surface of the skin in addition to imparting moisture. These agents contain an ingredient called Urea. Examples of such lotions include Umecta and Keralac.
It is important to have nice healthy skin to prevent breakdown or ulceration, in addition to helping the skin maintain its functions in protecting from foreign substances and body temperature regulation. The best time to apply moisturizing agents is within the first two minutes after you’ve showered, as the pores are the most open during that time interval and the moisturizer can penetrate into deeper layers of the skin.
If you’ve attempted over the counter lotions, such as the ones mentioned above without success, speak with your Podiatrist about trying a prescription moisturizer that will help remove keratinocytes. You may see healthier looking skin in no time.