Dear Dr. Bailey, A lot of skin care lines carry different products for dry skin and so called dehydrated skin. What is the difference between dry and dehydrated? Can the skin be oily and dehydrated? Can skin be dry and not dehydrated? Or is dehydrated skin only a marketing buzzword? Thanks a lot for giving great answers to great questions on your blog! I really like reading your answers and skin care advice. :) and thanks a lot for this answer too. Judith Hello Judith, I like this question! Yes in this context it's a marketing term but we can use it as a great jump off point for an interesting discussion about moisturizers and skin hydration. Skin moisture is actually water, not oil and this is why the topic is both confusing and fun. There are different ways to trap water in the skin. There are also some conditions that cause the skin to lose more water than is good for it, causing it to become overly dry and irritated. So, the long and fun answer: Moisturizers traditionally work by utilizing an oil, which when applied right after washing/wetting the skin will trap water by sealing over the skin and preventing evaporation. Skin with adequate trapped water is considered hydrated. Some of my favorite moisturizing oils are shea butter, jojoba oil, coconut oil, and sesame oil. Mineral oil works really well too, in spite of the fact that it gets a bad rap for being a petroleum product. Oily skin will hold more moisture because it produces its own moisturizing oil, which is very efficient and wonderful until the oily shine becomes annoying. Harsh soaps will remove the oil and it takes time to reproduce it so any absorbed water from washing may have evaporated by the time the oil begins to re-coat the skin. That said, people with oily skin usually don't like oil containing moisturizers because they have enough oil and oily shine already. There are non-oil ingredients in skin care products that can bind water too. These are especially great for oily skin moisturizing, but every skin type benefits from them. Some of my favorite oil free moisturizing ingredients are
- hyaluronic acid (sodium hyaluronate)
- alpha hydroxy acids.
2. A moisturizing cream with squalane, glycerine and possibly an AHA (glycolic acid) and my favorites are Daily Moisturizing Face Cream for Oily to Normal Skin and Glycolix Elite Face Cream with 15% glycolic acid
Skin can have suboptimal water content and be considered relatively dehydrated. This is most likely to happen when your skin is irritated to the point that it's barrier function is compromised and moisture escapes. Conditions that harm the barrier strength of your skin include:
- Repeated contact with harsh soaps (for sensitive skin this can include products with the sodium laurel sulfate family of ingredients) or harsh chemicals (like rubbing alcohol or household cleaners).
- Rashes such as facial dandruff that can cause a compromised barrier and water loss.
- Having a genetic tendency for eczema, asthma and allergies that means you may also have an inherently vulnerable skin barrier and are one of the classic 'sensitive skin' people.
- Exposure to harsh environments such as windy, cold climates, or simply going between cold outdoor temperatures and heated indoor environments which can irritate the skin and cause water loss.