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fmxkid

some helpful information i found online

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Occlusivity

The skin is the body's largest organ. The lungs breathe, and so does the skin, so to speak: The "breathing" skin provides an exit for toxins and chemicals--respiration in the form of perspiration. Lotions and salves that occlude this exit may initially soften the skin by keeping moisture from escaping, but may actually inhibit the overall health of the individual, besides weighing down the skin and causing it to sag and age. Nutrients applied to the skin that improve the skin's health may have a positive effect on the whole body, because they are absorbed into the bloodstream through the skin. When we choose body-friendly skin care, two important criteria come into play: that the products not be toxic to our skin or our bodies, and that they not be occlusive-allowing nutrients in and toxins out. The bonus comes when the ingredients that are allowed in also bring the skin into balance and nourish it. This is the topic of Part III of our series of articles: What Nutrients and Ingredients are Important for Healthy Skin? (late September 2005). Here we address ingredients common to "natural" skin care that may be occlusive and/or comedogenic. Look up "occlusivity" on the web and you will find hundreds of references to occlusivity and its benefits. The reason companies tout the benefits of occlusivity is that it holds water in the skin. When water can't escape, the skin stays soft and moist, and that sounds like a good thing. Imagine wrapping your skin with plastic wrap and wearing it around all day-an extreme example of occlusivity. Pretty soon it would start to stink in there as the toxins that usually escape with perspiration and generally evaporate into the air get trapped between the skin and the plastic. Now imagine that those same toxins can't leave the bloodstream because the skin's normal respiration is blocked. Where will they go? In some cases, they fester under the skin and form deep-down blemishes; in extreme cases, where occlusive lotions are used all over the body for extended periods, they may deposit in the liver and add to the body's toxic load.

Sometimes it may be beneficial to use occlusive salves for a limited time. If you want to climb Mt. Everest, for example, or ski at high altitude where the air is thin and dry and you are close to the sun, it's a good idea to wear a lotion that holds the water in the skin. For babies with diaper rash, it's good to use a salve that keeps the water away from the skin! For most of us, these are not constant conditions, and treatments that hold water in over time are undesirable.

Standard cosmetics experts may disagree with this reasoning. Paula Begoun in Don't Go to the Cosmetics Counter Without Me (5th ed., 2001) states: "According to many 'natural' cosmetics companies, mineral oil (and petrolatum) comes from crude oil (petroleum), is used in industry as a metal-cutting fluid, and therefore can harm the skin by forming an oil film and suffocating it. . . . This foolish, recurring misinformation about mineral oil and petrolatum is maddening. After all, crude oil is as natural as any other earth-derived substance. . . Mineral oil and petrolatum . . . can keep air off the skin to some extent, but . . . it doesn't suffocate the skin!" (pp. 11-13). She also states that antiperspirants "cannot absorb into the skin . . ." (p. 14). I maintain that anything rubbed onto the skin will be absorbed, as long as the molecules are small enough to pass through the skin membrane; this is how patches work to deliver medication. Although Begoun makes a good point that crude oil is "natural," I believe in making educated choices of which earth-derived substances we apply to the skin, and crude oil is not on my list.

It should be noted that there are degrees of occlusivity: If an ingredient is occlusive when used by itself, it will be less so when used in combination with non-occlusive ingredients. A small amount of beeswax used to emulsify jojoba and water will be far less occlusive than rubbing beeswax alone onto the skin. With that in mind, besides mineral oil and petrolatum, here are some of the more common occlusive ingredients found in "natural" skin care:

a. beeswax and other waxes

b. castor oil

c. cocoa butter

d. dimethicone

e. honey

f. lanolin

g. sunflower oil and other vegetable oils

3. Comedogenicity

Unlike occlusive oils like mineral and sunflower oil, which do not penetrate, comedogenicity refers to the tendency of a substance to get into the skin's pores and clog them. This is especially bothersome in face care products, where clogged pores may lead to acne and blackheads. The word comedo is the medical term for blackhead, so comedo+genic means "friendly to blackheads." Some cosmetic-ingredient glossaries equate "non-comedogenic" with "non-occlusive," but that is a misunderstanding; while beeswax, mineral oil and zinc oxide (among others) are known to be occlusive, they are non-comedogenic. This is because they lie on top of the skin and do not penetrate. Others, like sunflower oil, may be both occlusive and (somewhat) comedogenic.

"Note: Even somewhat or very comedogenic ingredients can be present in non-comedogenic formulas when used at percentages low enough that the end formula won't clog pores" (ibid.). The important point is to look at their relative position in the ingredients list. If a comedogenic ingredient is toward the top, then it is probably present in a quantity large enough to clog pores. Unfortunately it is impossible from the ingredients list to know whether for example ingredient #5 represents 20% of the formula or 2%. Thus we need to be able to trust the manufacturer when the label states "non-comedogenic."

4. Effectiveness

Let us assume that every skincare company's raison d'etre (before or after the profit motive) is to create products that make the skin feel and look good, and that probably means it's soft and not dry. Add some additional goals--anti-aging, anti-acne, skin-smoothing--and you've covered most of the bases. Most skincare products, "natural" or otherwise, achieve these goals by using occlusive ingredients that hold moisture in and keep the skin soft and "plump."

If, however, we are looking for the beauty of overall glowing good health in the skin, we need to ask for more than this from our skin care. We agree with Charles DePrince, president of GoForLife Labs, who states:

"The idea of 'natural' could mean a product containing all natural ingredients; however, I believe there should be a more significant meaning to the idea. I think the natural course to attaining beauty is a healthier and potentially more lasting one than with the use of harsh or radical treatments such as Botox, face lifts and peeling. The 'natural' idea would be to support the living and natural cells of our skin with nutrients that could support such things as the body's natural ability to retain moisture, to support natural collagen development, or to reduce hyperpigmentation. This way, by supporting the natural health of the skin, I believe the cumulative effect would be to develop healthier skin as both the path to and result of beauty."

In the third and final article of this series, to be published in late September, we will discuss skincare ingredients that work from the inside out to support and nourish the skin, bring it into balance, and keep it healthy and young-looking. Meanwhile, we recommend as a minimum that skincare products be non-toxic, non-occlusive, non-comedogenic, and soften and moisturize. We also recommend using fewer products, and avoiding synthetic fragrances and perfumes. Become an avid reader of ingredients labels!

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