What is corneotherapy?

The basic idea behind corneotherapy is that any problems apparent at the surface of the skin -- such as redness or inflammation -- are caused by an immune response produced by deeper layers of skin. This immune response, however, is spurred into action by an initial problem at the surface, chiefly a disruption in the protective layer of the stratum corneum. Through this reasoning, one can stop the unsightly and uncomfortable immune response by returning the outer layer of skin to a state of homeostasis. Once the epidermis is in a state of homeostasis, the risk of infection returns to normal, and excessive water loss can be prevented.

Because corneotherapy tackles the underlying cause (immune response) by treating the outer layer of skin, its practitioners refer to it as an "outside-in" therapy.

Normally, when you try to treat symptoms such as dryness (a result of excessive water loss), you can slow down or prevent healing of the problem that actually caused the water loss. For instance, using petroleum-based products locks moisture in by creating a new barrier through which water can't escape. However, doing so also prevents cellular respiration [source: McCord]. This slows down repair of the outer epidermis, which is actually the root of the problem.

Corneotherapeutic approaches favor using more breathable false barriers for short-term protection and prevention of water loss, which enables normal functioning of the skin-cell cycle and healing of the epidermis to occur beneath the applied false layer of oil or lotion.

This new understanding of skin care was first proposed and developed by Professor Albert M. Kligman in the 1990s. Kligman noticed that the creams we use to help infiltrate more active skin care agents past the barrier were effective all by themselves in treating the outer layer of skin, and that healing this outer layer removed the need to treat underlying layers with pharmaceutical agents.

Next, we'll take a closer look at some techniques of corneotherapy.

While base creams used in corneotherapy don't contain pharmaceutical agents that could potentially cause side effects, they often do contain substances that mimic or aid in the regeneration of skin structure.

One of these substances is derma membrane structure, or DMS. DMS is similar to the lipid content of the skin and not only aids in the skin's barrier function, but also facilitates skin regeneration. Holding to corneotherapeutic ideals, DMS doesn't contain preservatives, perfumes or emulsifiers, which can irritate or affect the skin's barrier integrity. How? When sensitive skin detects a foreign agent, even if it's just a light perfume additive, it spurs an immune response that disrupts the skin's normal regenerative process.

Liposomes and nanoparticles are also sometimes mixed into base creams for use in corneotherapy. These substances facilitate the release of linoleic acid and ceramides into the skin, which serve as building block materials for the repair of the stratum corneum.

Since skin treated through corneotherapy is by nature experiencing barrier problems, practitioners are careful to use only substances in creams that won't adversely affect the skin, especially knowing that they will penetrate into deeper layers. Certain substances, such as mineral oil or paraffin oil, may provide a secondary barrier against water loss, only to hinder repair of the problem itself.

For this reason, only substances with components that are similar in structure to the stratum corneum are used.

Other examples of this include:

A polysaccharide produced from yeast, CM-glucan, can be added to base creams to help make skin less sensitive to UV rays. As with other active agents, corneotherapists believe most substances used for UV protection are effective but ultimately damage the skin in the long run and maintain that the best protection from the sun can be had from blocking it with clothing alone.

The end result of treatment, Kligman (and others) believe, is a smoothly functioning stratum corneum that isn't constantly having to allocate resources to inflammatory responses in the presence of allergens. By achieving this, it's hoped that premature aging can be prevented and normal aging delayed as much as possible.

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