ecamsule. See Mexoryl SX.

ectoin. Skin-conditioning agent that also functions in cosmetics as a stabilizer. There is limited research demonstrating that ectoin helps protect skin from UVA damage and has efficacy and application characteristics that women tend to prefer in moisturizers. However, the research did not reveal to what the effects of ectoin were compared, or whether or not other ingredients (such as green tea or pomegranate extracts) may provide even better protection from environmental damage (Sources: Skin Pharmacology and Physiology, May 2007, pages 211–218, and September/October 2004, pages 232–237).

EDTA. Acronym for ethylenediaminetetraacetic acid, a stabilizer used in cosmetics to prevent ingredients in a given formula from binding with trace elements (particularly minerals) that can exist in water and with other ingredients to cause unwanted product changes to the texture, the odor, and the consistency. The technical term for ingredients that perform this function is chelating agent.

egg yolk. Egg yolk is mostly water and lipids (fats), especially cholesterol, which makes it a good emollient and water-binding agent for skin.

eicosapentaenoic acid. Fatty acid derived from salmon oil; it is a good emollient for skin. It has also been shown to inhibit collagen breakdown and improve cell function (Sources: European Journal of Dermatology, July-August 2007, pages 284–291; and Journal of Lipid Research, May 2006, pages 921–930). See fatty acid.

Elaeis guineensis. See palm oil.

elastin. Major component of skin that gives it flexibility. Sun damage causes elastin in skin to deteriorate. Elastin can be derived from both plant and animal sources and is used in cosmetics as a good water-binding agent. Elastin in cosmetics has never been shown to affect the elastin in skin or to have any other benefit, although it most likely functions as a water-binding agent.

elderberry. Has potent antioxidant properties (Source: Free Radical Biology and Medicine, July 2000, pages 51–60).

elecampane. Latin name Inula helenium; it is a plant that can be very irritating to the skin and can trigger allergic reactions (Source: Contact Dermatitis, October 2001, pages 197–204).

emollient. Supple, waxlike, lubricating, thickening agents that prevent water loss and have a softening and soothing effect on the skin. Please refer to Chapter Two, Healthy Skin: Rules to Live By, for additional information.

emu oil. The emu is a large, flightless bird indigenous to Australia, and emu oil has become an important component of the Australian economy. As a result there is research from that part of the world showing it to be a good emollient that can help heal skin; however, there is no research showing it has any anti-aging or anti-wrinkling effects. Emu oil’s reputation is driven mostly by cosmetics company claims and not by any real proof that emu oil is an essential requirement for skin.

English ivy extract. Can be a skin irritant due to its stimulant and astringent (skin-constricting) properties (Source: http://www.naturaldatabase.com).

ensulizole. Sunscreen agent, formerly known as phenylbenzimidazole sulfonic acid. Ensulizole is the established name that must be used on sunscreen labels (Source: http://www.fda.gov). It is primarily a UVB-protecting sunscreen agent, providing only minimal UVA protection. Ensulizole protects the skin from wavelengths of UV light in the range 290 to 340 nanometers, whereas the UVA range is 320 to 400 nanometers (Source: United States Pharmacopeia (USP), http://www.uspdqi.org/pubs/monographs/sunscreen_agents.pdf). For complete protection, this ingredient (as well as many other UVB-protecting sunscreen ingredients) must be paired with the UVA-protecting ingredients avobenzone (also called Parsol 1789 and butyl methoxydibenzoylmethane), titanium dioxide, zinc oxide, or Mexoryl SX; outside the United States it can also be paired with Tinosorb. Because ensulizole is water-soluble, it has the unique characteristic of feeling lighter on skin. As such, it is often used in sunscreen lotions or moisturizers whose aesthetic goal is a non-greasy finish (Source: http://www.emedicine.com/derm/topic510.htm).

Enteromorpha compressa extract. Extract from green algae. See algae.

enzymes. Vast group of protein molecules, produced by all living things, that act as catalysts in chemical and biological reactions, including photosynthesis, helping cells communicate, inhibiting free-radical damage, and much more. Enzymes are used in skin-care products to facilitate exfoliation, to help overall biological processes in skin that have slowed down because of age or sun damage, and to inhibit free-radical damage. Enzymes accelerate biochemical reactions in a cell that would proceed minimally or not at all if the enzymes weren’t present. Most enzymes are finicky about how and under what conditions they will act. Sometimes several enzymes are required to carry out a particular chemical reaction, and their actions are affected by temperature and pH. Some enzymes depend on the presence of other enzymes, called coenzymes, to function, or they depend on a specific body temperature. It would require an exceptionally complicated process to stimulate enzyme activity via topical application to the skin. Enzymes are divided into six main categories, including oxidoreductases, transferases, hydrolases, lyases, isomerases, and ligases. The names of most individual enzymes end in –ase. See bromelain, papain, and oxidoreductases.

epidermal growth factor (EGF). Stimulates cell division of many different cell types. There is research showing it to be helpful for wound and burn healing (Sources: Journal of Controlled Release, April 2007, pages 169–176; Journal of Burn Care and Rehabilitation, March–April 2002, pages 116–125; and Journal of Dermatologic Surgery and Oncology, July 1992, pages 604–606). There is also research showing that its effect is no different from that of a placebo and that it may not be effective at all (Sources: The British Journal of Surgery, February 2003, pages 133–146; Wounds, 2001, volume 13, number 2, pages 53–58; and Plastic and Reconstructive Surgery, August 1995, pages 251–254). It can have anti-inflammatory properties when applied to skin (Source: Skin Pharmacology and Applied Skin Physiology, January-April 1999, pages 79–84), although it also can promote tumor growth (Source: Journal of Surgical Research, April 2002, pages 175–182). In general, the potentially frightening consequences of growth factors can come into play when they are taken internally, as in certain cancer treatments (interleukin and interferon are growth factors), because they can be highly mitogenic (causing cell division), and at certain concentrations and lengths of application can cause cells to overproliferate. This overabundance of cells causes problems, one result of which is cancer. No one is exactly certain what happens when EGFs are applied to healthy, intact skin, but there is concern that with repeated use EGFs can cause skin cells to overproduce, and that’s not good (psoriasis is an example of what happens when skin cells overproduce).

All of the research that does exist on EGFs has primarily studied their short-term use for wound healing. See human growth factor.

epigallocatechin-3-gallate. See green tea.

Epilobium angustifolium extract. Extract derived from a plant commonly known as fireweed or willow herb. Can have antimicrobial (Source: Il Farmaco, May–July 2001, pages 345–348) and anti-irritant properties for skin (Source: Journal of Agricultural Food Chemistry, October 1999, pages 3954–3962).

Equisetum arvense. See horsetail extract.

ergocalciferol. Technical name for vitamin D. See vitamin D.

ergothioneine. Component of animal tissue that has potent antioxidant properties (Sources: Journal of Cosmetic Dermatology, September 2007, pages 183–188;Biomedicine and Pharmacotherapy, September 2006, pages 453–457; and Food and Chemical Toxicology, November 1999, pages 1043–1053).

Eriobotrya japonica. See loquat extract.

erythropoietin (Epo). Stimulates the growth of cells that carry oxygen throughout the body (Source: Melanoma Research, August 2006, pages 275–283). See human growth factor.

erythrulose. Substance chemically similar to the self-tanning agent dihydroxyacetone. Depending on your skin color, there can be a difference in the color effect with erythrulose. However, dihydroxyacetone completely changes the color of skin within two to six hours, while erythrulose needs about two to three days for the skin to show a color change.

escin. Extract derived from horse chestnut (Aesculus hippocastanum), this ingredient has been prescribed as an oral supplement to reduce some symptoms of chronic vein insufficiency, such as varicose veins, pain, tiredness, tension, swelling in the legs, itching, and edema. However, because horse chestnut contains significant amounts of the toxin esculin, it can be lethal, and some experts recommend not using it. When applied topically, however, there is research showing that a gel containing 2% escin can improve circulation. Results from another study showed a reduction in inflammation in sports injuries when escin was combined with heparin (a mucopolysaccharide used as an anti-clotting medication) and a form of salicylic acid (diethylammonium salicylate). Escin is also a potent antioxidant. As a skin-care ingredient escin clearly has a place, but as for improving cellulite that’s an entirely different story. While it may seem logical that blood flow and cellulite are related, the research just isn’t there to support the notion (or your thighs). Plus, cellulite products contain far less of this ingredient than the amount used in the studies (Sources: British Journal of Sports Medicine, 36 June 2002, pages 183–188; Angiology, March 2000, pages 197–205; http://www.naturaldatabase.com; Archives of Dermatology, November 1998, pages 1356–1360; and International Journal of Cosmetic Science, December 1999, page 437).

esculin. Component of horse chestnut, it is considered a toxin and is not recommended for skin (Source: Clinical Pharmacology, 2002, http://cponline.hitchcock.org/).

essential oil. See volatile oils.

ester. A compound formed from the reaction between an alcohol and an acid via the elimination of water. Triesters (groups of three esters) form the backbone of many fats, waxes, and oils that have emollient and skin-conditioning properties (Source: A Dictionary of Chemistry, Third Edition, Oxford Paperback, 1996). Almost all of the esters used in cosmetic products are non-irritating and in most cases are quite beneficial for dry skin.

Ester-C. Trade name for a combination form of vitamin C that contains mainly calcium ascorbate, but in addition contains small amounts of the vitamin C metabolites dehydroascorbic acid (oxidized ascorbic acid), calcium threonate, and trace levels of xylonate and lyxonate. The manufacturer of this ingredient states that the metabolites, especially threonate, increase the bioavailability of the vitamin C in the product, and that they performed a study in humans demonstrating the increased bioavailability of vitamin C in Ester-C. However, this study has not been published in a peer-reviewed journal. There is a small, in vitro study that supports the notion that Ester-C is more potent than ascorbic acid by itself (Source: Medical Science Monitor, October 2007, pages 205–210). A small published study of vitamin C bioavailability in eight women and one man found no difference between Ester-C and commercially available ascorbic acid tablets with respect to the absorption and excretion of vitamin C (Source: The Bioavailability of Different Forms of Vitamin C, The Linus Pauling Institute, Oregon State University, http://www.orst.edu/dept/lpi/ss01/bioavailability.html). There also are studies that show no difference when comparing the effects of Ester-C with those of ascorbic acid (Source: Biochemical Pharmacology, June 1996, pages 1719–1725).

estradiol. One of the three main forms of estrogen produced by the body; the other two are estrone and estriol. Estradiol is the most physiologically active form of estrogen. Many hormone replacement therapy (HRT) and birth-control prescription drugs contain estradiol. One study revealed that topical application of estradiol has photoprotective properties due to its anti-inflammatory nature, while another small-scale study showed that topical application of 0.01% estradiol had collagen-stimulating effects on postmenopausal skin (Sources: Proceedings of the National Academy of Sciences of the United States of America, August 22, 2006, pages 12837–12842; and European Journal of Obstetrics, Gynecology, and Reproductive Biology, February 2007, pages 202–205). However, as a component of estrogen, it is not without its risks and unknowns.

Decreased production of estrogen by the ovaries can lead to symptoms such as hot flashes, night sweats, vaginal dryness, urinary tract infections, depression, and irritability. With a physician’s prescription, licensed pharmacists may make a combination of natural estrogens. Whether or not natural estrogens are safe has not been well-researched.

Although HRT can prevent associated problems with loss of estrogen in perimenopausal and menopausal women, it is no longer being prescribed without caution because of studies that show there is an increased risk of breast cancer, heart attacks, strokes, gall bladder disease, and blood clots (Source: Annals of Internal Medicine, http://www.acponline.org/journals /annals/hrt.htm).

Topically, according to the FDA (http://www.fda.gov), “The estrogen content of an OTC product, be it a drug or a drug as well as cosmetic, may not exceed 10,000 IU per ounce, and users must be directed to limit the amount of product applied daily so that no more than 20,000 IU of estrogen or equivalent be used per month. Some estrogen-containing products have been claiming to prevent or reduce wrinkles, treat seborrhea, or stimulate hair growth. The Advisory Review Panel on OTC Miscellaneous External Drug Products has concluded that there are inadequate data to establish the safety of these products and that they are ineffective and may therefore be misbranded, even if marketed as cosmetics without making medicinal claims … In a Final Rule, published in the Federal Register of September 9, 1993, 58 FR 47608, the FDA accepted this panel’s recommendation and determined that all topically-applied hormone containing drug products for OTC human use are not generally recognized as safe and effective and are misbranded.”

ethanol. See alcohol.

ethoxydiglycol. See solvent.

ethyl alcohol. See alcohol.

ethyl macadamiate. Mixture of fatty acids from macadamia nut oil. See fatty acid and macadamia nut oil.

ethyl vanillin. Flavoring agent derived from vanilla. It has antioxidant properties (Source: Journal of Agricultural and Food Chemistry, April 2004, pages 1872–1881).

ethylhexyl stearate. See stearic acid.

ethylparaben. See parabens.

eucalyptus extract. Extract that may have antibacterial, antifungal, and antiviral properties on the skin (Source: Skin Pharmacology and Applied Skin Physiology, January–February 2000, pages 60–64). It also may be a skin irritant, particularly on abraded skin (Sources: Clinical Experimental Dermatology, March 1995, pages 143–145; and http://www.alternativedr.com/conditions/ConsHerbs/Eucalyptusch.html). See counter-irritant.

eucalyptus oil. See eucalyptus extract.

Eugenia aromatica. See clove oil.

Eugenia caryophyllus. See clove oil.

eugenol. See clove oil and methyleugenol.

Euphrasia officinalis. See eyebright.

evening primrose oil. Can have significant anti-inflammatory and emollient benefits for skin (Sources: Surgeon, February 2005, pages 7–10; Skin Pharmacology and Applied Skin Physiology, January–February 2002, pages 20–25; and Journal of Agricultural Food Chemistry, September 2001, pages 4502–4507). However, whether or not evening primrose oil can mitigate certain symptoms of premenstrual syndrome (PMS) is unknown. “Trials of evening primrose oil have also had conflicting results; the two most rigorous studies showed no evidence of benefit” (Source: Journal of the American College of Nutrition, February 2000, pages 3–12). See gamma linolenic acid.

Ext. D&C. Type of coloring agent. According to the FDA (http://www.fda.gov), when Ext. D&C is followed by a color, it means that the color is certified as safe for use only in drugs and cosmetics to be used externally, but not around the eyes or mouth. It is not safe for foods.

eyebright. A plant; although the name sounds like it would be beneficial for the eye area, there are no studies demonstrating it has any benefit for the eye area or skin. The information about this plant’s effect on the skin or the eye is strictly anecdotal and ophthalmic use may be harmful (Source: www.naturaldatabase.com).