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What do you mean by “moisturize” your skin? And “hydrate”?

Here are the actual meanings of the words according to the dictionary:

Moisture: water or other liquid diffused in a small quantity as vapor, within a solid, or condensed on a surface.

Hydration: the process of causing something to absorb water.

In short: water! In my opinion, these two words are used as synonyms in the industry, and they mean “give back to the skin water that has been lost to the air because the air is dryer than the skin”.

The outermost layer of the skin, the stratum corneum, limits water loss from the body to the environment and allows us humans, organisms that depend totally on water, to walk around in the Arizona desert and still be able to live. Many of the chemical components on the skin are hydrated and they require a certain aount of water for the skin to function.

The air is dryer than the skin is most conditions. In Arizona, today, relative humidity was 8%. Low humidity feels great because we can dissipate heat through the water that evaporates from our bodies, meaning that “dry heat” is a lot more comfortable that “humid heat” (as in Miami).

Sweating is one way we keep our bodies cool: it causes a decrease in core temperature through evaporation at the skin surface. As high energy molecules evaporate from the skin, releasing energy absorbed from the body, the skin and superficial vessels decrease in temperature. Cooled venous blood then returns to the body’s core and counteracts rising core temperatures. This is the same principle we use in evaporative cooling of buildings, and it only works when the relative humidity (RH) of the air is low, i.e. when the actual humidity of the air is lower than what it would be when the air is saturated with water at that temperature.

Our skin does a great job of keeping water inside our bodies as we walk around, especially taking into account that we evolved from organisms that lived in water. But living in a cold climate the outdoor temperature causes lower low humidity air to flow around. Although it may be snowing and the relative humidity outdoors is high, once that air comes into a building and heats up, its new relative humidity (for the actual temperature indoors) is very low.

What happens then? Either in Arizona in the Summer (indoors or outdoors) or in Alaska (indoors) in the Winter, our skin will loose too much water to the outside environment. And although the epidermis is well equipped to slow down water loss, eventually the skin will loose too much water. The same will happen to nasal passages, making it easier for viruses to penetrate (!).   And the skin? Our skin will feel uncomfortably dry, which is useful  because it will remind us that we are no longer aquatic animals and we need to moisturize (hydrate) our skin and protect the skin barrier. 

How to moisturize/hydrate? A serum or cream will restore humidity to the drying skin and will make the skin feel comfortable again. Long term, it is important to keep the skin barrier intact, and this means to NOT let the skin get older, thinner and incapable of doing its job as a barrier.

Skin Actives gives you all the tools you need to keep your skin hydrated and the skin barrier intact. Almost any water containing serum or cream will do when it comes to hydration. To keep your skin working young and providing an effective barrier to water loss, go for our collagen serums, vitamin A cream and ELS serum (every lipid serum) so that you give your skin the building blocks and signals it requires to constantly repair itself.

Claims on this page have not been evaluated by the FDA and are not intended to diagnose, cure, treat or prevent any disease.