Skin Care Cosmetics Ingredients Glossary

P

P. elisabethae. The “P.” is short for the genus Pseudopterogorgia. See sea whip extract.

PABA. See para-aminobenzoic acid (PABA).

padimate O . Sunscreen agent that protects skin primarily from the sun’s UVB rays.

Padina pavonica extract. See algae.

Paeonia albiflora extract. See peony flower.

Paeonia suffruticosa extract. See peony root extract.

palm oil. Has emollient and antioxidant properties for skin. See antioxidant and natural moisturizing factor (NMF).

Palmaria palmata extract. Extract from a type of algae whose common name is dulse. See algae.

palmarosa oil. See geranium oil.

palmitic acid. Detergent cleansing agent that also creates foam and can be drying. See surfactant.

palmitoyl pentapeptide 3. Trade name Matrixyl, a fatty acid mixed with amino acids. The only research showing this has any significance for skin was carried out by the ingredient manufacturer, Sederma. In their research, three different “half-face” studies with a total of about 45 participants showed it to be better than a retinol or vitamin C product. Without independent substantiation, however, there is no way to know how accurate this company-funded research is. Further, according to Sederma’s research, the recommended concentration for this ingredient is 3% to 5% and there are few, if any, lines that include more than just a trace amount in their products. See amino acid and fatty acid.

Panax ginseng root extract. Root extract that may have potent antioxidant properties (potentially anti-cancer) and may promote wound healing. Whether or not it can have an impact on cellulite is unknown (Sources: Journal of Agricultural and Food Chemistry, April 2006, pages 2558–2562; Phytotherapy Research, January 2005, pages 65–71; Archives of Pharmacal Research, February 2002, pages 71–76; and Cancer Letters, March 2000, pages 41–48).

Panicum miliaceum. See millet seed extract.

pansy extract. Extract for which there is a small amount of research showing it has anti-inflammatory and antioxidant properties (Source: www.naturaldatabase.com).

pantethine. Also known as pantothenic acid. See pantothenic acid.

panthenol. Alcohol form of vitamin B. See pantothenic acid.

pantothenic acid. Also called vitamin B5, and often touted as being effective for acne. However, there is only one study supporting this notion and it dates from the early 1980s. There is no current research showing this to be an effective treatment for acne, but there is a small amount of research showing that it can be effective for hydration and wound healing.

papain. Enzyme extracted from papaya. Applied topically, papain can cause severe irritation, itching, and allergic reactions. There is one study showing it may be effective for exfoliation, but only in a pure concentration.

Papaver somniferum seed. Latin name for the opium poppy seed. See opium poppy seed.

papaya extract. Extract that is the source of papain, which theoretically can have exfoliating properties on skin, although the majority of the research was not performed on skin. Papaya can be a skin irritant. See enzymes.

para-aminobenzoic acid (PABA). Sunscreen ingredient rarely used since the 1990s because of strong potential for allergic reactions.

parabens. Group of preservatives, including butylparaben, propylparaben, methylparaben, and ethylparaben, that are the most widely used group of preservatives in cosmetics.

paraffin. Waxy, petroleum-based substance used as a thickener in cosmetics.

Paraffinum liquidum. See mineral oil.

Parsol 1789. See avobenzone.

Passiflora edulis extract. See passion fruit extract.

passion fruit extract. There is no research showing this has any benefit for skin.

patchouli. Fragrant oil derived from mint. It contains eugenol and can be a skin sensitizer and irritant. See counter-irritant.

Paullinia cupana seed extract. Also called guarana, this extract is used primarily in herbal supplements and beverages as a stimulant. In animal studies (mice), it has been shown to affect fat metabolism. There is also research showing that repeated use of guarana can result in persistent increases in heart rate and blood pressure as well as in unfavorable actions on glucose and potassium homeostasis. Such effects could be detrimental in persons with hypertension, atherosclerosis, or glucose intolerance—conditions that are strongly associated with obesity. Guarana is sometimes used in cellulite products because of its theophylline and caffeine components. Research has shown it can be absorbed into the skin. Whether or not topical application can affect fat metabolism or have other associated health risks in humans is not known.

pawpaw extract. See papaya extract.

peanut oil. Emollient plant oil similar to all nonfragrant plant oils.

pecan oil. Emollient plant oil similar to all nonfragrant plant oils.

pectin. Natural substance found in plants, especially apples, and used in cosmetics as an emulsifier and thickening agent.

PEG. PEG is the acronym for polyethylene glycol. Various forms of PEG compounds are mixed with fatty acids and fatty alcohols to create a variety of substances that have diverse functions in cosmetics, including acting as surfactants, binding agents (to keep ingredients blended), stabilizers, and emollients. See polyethylene glycol.

PEG-100 stearate. See PEG compound and thickening agent.

PEG-120 methyl glucose dioleate. See surfactant.

PEG-150 distearate. See thickening agent.

PEG-40 hydrogenated castor oil. Emollient ingredient that is a mixture of polyethylene glycol (PEG) with castor oil. See polyethylene glycol (PEG) and castor oil.

PEG-80 sorbitan laurate. Mild surfactant. See surfactant.

Pelargonium graveolens oil. See geranium oil.

pellitory. Plant whose root extract can cause skin irritation; its safety is unknown.

pentadecalactone. Synthetic fragrance used in cosmetics.

pentaerythrityl tetraoctanoate. Synthetic compound as an emollient and thickening agent. See thickening agent.

pentasodium pentetate. Used as a chelating agent in cosmetics to prevent various mineral components from binding together and negatively affecting the formulation.

peony flower. European flower used topically for treating a variety of skin diseases, including skin fissures (painful cracks in skin). Evidence of its effectiveness for these purposes is anecdotal. There is not enough known about the effects of peony flower to substantiate its use or safety in cosmetic products (Source: www.naturaldatabase.com).

peony root extract. There is research showing that the root of the peony plant can have anticancer properties as well as antioxidant properties.

peppermint. Both the oil and the extract can have antimicrobial properties. See counter-irritant.

peptide. Peptides are portions of proteins, which are long chains of amino acids.

Perilla ocymoides. Also known as beefsteak plant. Like many plants, the leaves contain flavones which help the plant survive in natural sunlight. Although the oil from this plant is best avoided due to the risk of contact dermatitis, its extracts may have anti-inflammatory activity as well as functioning as antioxidants. There is no substantiated research on human skin proving Perilla ocymoidies’ has benefit, but we know that flavones can be helpful and research on animals has shown this extract has anti-tumor ability when skin is exposed to UVB light.

Persea gratissima oil. See avocado oil.

Persicaria hydropiper. Also known as water pepper. All parts of this plant extract have been shown in vitro to be not only a potent antioxidant but also able to inhibit the expression of collagen-depleting MMP-1 when applied to human fibroblast cells. See matrix metalloproteinases.

petitgrain mandarin. See mandarin orange oil or extract.

petrolatum. Vaseline is pure petrolatum. For some unknown and unsubstantiated reason, petrolatum has attained a negative image in regard to skin care, despite solid research to the contrary. Topical application of petrolatum can help the skin’s outer layer recover from damage, reduce inflammation, and generally heal the skin. See also mineral oil.

PHA. See polyhydroxy acid.

phenoxyethanol. Common cosmetic preservative that is considered one of the less irritating ones to use in formulations. It does not release formaldehyde. See preservatives.

phenoxyisopropanol. Alcohol used as a solvent and preservative. See solvent and preservative.

phenyl trimethicone. Silicone with a drier finish than dimethicone. See silicone.

phenylalanine. See amino acid.

phloretin. A flavonoid substance derived from apples and the bark of apple trees. As for phloretin pertains to topical application to skin, in-vitro and animal research has shown that it has antioxidant ability, can interrupt melanin synthesis to potentially reduce skin discolorations, inhibits the formation of MMP-1 (which helps protect fibroblasts in skin’s support structure from breaking down), and also serves as a penetration enhancer, which means it can, when properly formulated, help other beneficial ingredients go beyond the superficial layers of skin.

phosphatidylcholine. Active ingredient in lecithin. Every cell membrane in the body requires phosphatidylcholine (PC). It is also a major source of the neurotransmitter acetylcholine. Acetylcholine is used by the brain in areas that are involved in long-term planning, concentration, and focus, but all of that information is associated with ingesting PC, not putting it on the skin. PC is considered a very good water-binding agent and aids in the penetration of other ingredients into the skin. It absorbs well without feeling greasy or heavy (although other ingredients can perform similarly, including glycerin, ceramides, and hyaluronic acid) See lecithin and water-binding agent.

phosphatidylethanolamine. See phospholipid.

phospholipid. Type of lipid (fat) composed of glycerol, fatty acids, and phosphate. Phospholipids are essential to the function of cell membranes by providing a stable surrounding structure. Lecithin is an example of a phosopholipid. See glyceryl ester and natural moisturizing factor (NMF).

phosphoric acid. Used as a pH adjuster in cosmetics and skin-care products.

photosensitizer. Ingredient that can cause the skin to have an irritated or inflamed reaction when exposed to sunlight.

Phyllanthus emblica fruit extract. Extract that has antioxidant and anti-inflammatory properties.

phytantriol. Hair- and skin-conditioning agent that also has water-binding properties.

phytic acid. Component of plants that has antioxidant properties.

phytoestrogen. See plant estrogen.

phytonadione. One form of vitamin K. See vitamin K.

phytosphingosine. Long-chain, complex fatty alcohol that functions as a water-binding agent and also has preservative qualities. Its name is derived from the term sphingoid, coined in 1884 by chemist J. L. W. Thudichum because the way the molecules of this substance lined up reminded him of the riddle of the Sphinx. Research shows it is effective in regulating damaged or diseased epithelial cells. It seems this ingredient can also be a cell-communicating ingredient, albeit one that is best for compromised skin.

phytosterol. Cholesterol-like molecules found in all plant foods; the highest concentrations are found in vegetable oils. Phytosterols in the natural diet may lower cholesterol. However, regarding topical application, there is research showing that the high lipid content of phytosterols can make the skin extremely sensitive to light.

pine oil. Can have disinfectant properties (Source: Antimicrobial Agents and Chemotherapy, December 1997, pages 2770–2772), but it can also be a potent skin irritant and should never be used on abraded or chafed skin. May be used as an extract or oil.

pineapple extract. Contains the enzyme bromelain, which can break down the connecting layers between skin cells to exfoliate skin. However, bromelain used alone is a more effective source of exfoliation, and does not have the irritating properties of the pineapple. See bromelain.

pinecone extract. Components of this extract, specifically linolenic and linoleic acids, can have antioxidant properties (Source: Tree Physiology, June 2002, pages 661–666) and antibacterial properties for skin (Source: International Journal of Food Microbiology, May 2000, pages 3–12).

Pinus lambertiana wood extract. Pine extract that may have skin-sensitizing properties.

Pinus sylvestris extract. See pinecone extract.

Piper nigrum. See black pepper.

pistachio seed oil. Emollient plant oil with uses similar to peanut oil in cosmetics. See peanut oil.

Pistacia vera seed oil. See pistachio seed oil.

Pisum sativum. Latin name for the garden pea. It does have antioxidant activity, but there is no research showing that it can reduce cellulite.

plasticizing agents. Ingredients that place a thin layer of plastic over the skin. Typically these are used in facial masks so they can be peeled off the skin. See film-forming agent.

plum extract. Extract of Prunus americana that may have antioxidant activity when applied topically.

Pogostemon cablin. See patchouli.

poloxamers. See surfactant.

polyacrylamide. See film-forming agent.

polyaminopropyl biguanide. Synthetic polymer that functions as a preservative.

polybutene. Polymer derived from mineral oil and used as a thickener and lubricant.

polycaprolactone. Biodegradable thermoplastic polymer derived from the chemical synthesis of crude oil. It may have application in supporting skin-tissue growth for the purposes of skin grafts.

polyethylene glycol. Also listed as PEG on ingredient labels, polyethylene glycol is an ingredient that self-proclaimed “natural” Web sites have attempted to make notoriously evil. They gain a great deal of attention by attributing horror stories to PEG, associating it with antifreeze (however, antifreeze is ethylene glycol, not polyethylene glycol), and there is no research indicating that PEG compounds pose any problem for skin. Quite the contrary: PEGs have no known skin toxicity and can be used on skin with great results. The only negative research for this ingredient indicates that large quantities given orally to rats can cause tumors, but that is unrelated to topical application.

Polyethylene, when it is not combined with glycol, is the most common form of plastic used in the world. It is flexible and has a smooth, waxy feel. When ground up, the small particles are included in scrubs as a gentle abrasive. When mixed with glycol, it becomes a viscous liquid. In the minuscule amounts used in cosmetics, it helps keep products stable and performs functions similar to those of glycerin. Because polyethylene glycol can penetrate skin, it is also a vehicle that helps deliver other ingredients deeper into the skin. It is also used internally in medical procedures to flush and clean the intestinal tract. See propylene glycol.

polyglucuronic acid. See film-forming agent.

polyglycerol monostearate. Used as an emollient and thickening agent in cosmetics. See glyceryl ester.

polyglyceryl methacrylate. See film-forming agent.

polyglyceryl-3 methylglucose distearate. See glyceryl ester.

Polygonum cuspidatum root extract. Extract of the Japanese knotweed plant. When eaten it may have weak estrogenic activity and antitumor activity. It also has antioxidant properties.

polyhydroxy acid. Ingredients such as gluconolactone and lactobionic acid are types of polyhydroxy acid (PHA). They are supposed to be as effective as AHAs but less irritating. Gluconolactone and lactobionic acid are chemically and functionally similar to AHAs. The significant difference between them and AHAs is that gluconolactone and lactobionic acid have larger molecular structures, which limits their ability to penetrate into the skin, resulting in a reduction of irritating side-effects.

polyhydroxysteatic acid. Synthetic polymer related to stearic acid. It functions as a suspending agent.

polyquaterniums. Group of ingredients used primarily in hair-care products for their antistatic and film-forming properties. They can have water-binding properties for skin due to the sheer “plastic” film layer they create on skin.

polysaccharide. Natural component of skin that can be a good water-binding agent and potentially have antioxidant properties. See mucopolysaccharide and natural moisturizing factor (NMF).

polysorbate-20. See polysorbates.

polysorbates. Large group of ingredients most often derived from lauric acid, which is derived from coconuts. Polysorbates function as emulsifiers and also have mild surfactant properties; Some polysorbates are derived from the food ingredient sorbitol, which occurs naturally in many fruits, while others have a fatty acid component. Polysorbates are considered non-toxic and safe as used in the concentrations found in cosmetic and food products (in food products, polysorbates function as a stabilizer).

polyvinyl alcohol. See plasticizing agents.

polyvinylpyrrolidone. Usually listed on ingredient labels as PVP or PVP copolymer, it is one of the primary ingredients used in hairstyling products to hold hair in place. When present in minuscule amounts in skin-care products, it places an imperceptible film over the skin that is considered to be water-binding and that helps give the appearance of firmer skin. It can be a skin sensitizer for some individuals. See film-forming agent.

pomegranate extract. Extract that contains ellagic acid, and is considered effective as an anticarcinogen and antioxidant when taken orally. There is no research showing what effect, if any, this extract can have on skin (Sources: Journal of Agricultural Food Chemistry, January 2002, pages 81–86, and 166–171; and International Journal of Oncology, May 2002, pages 983–986).

Poria cocos extract. Also known as Hoelen and Fu ling. Extract derived from a mushroom, which has antioxidant and anti-inflammatory properties.

Porphyridium cruentum extract. Extract derived from a type of red algae. There is research showing components of red algae contain the omega-3 fatty acid eicosapentaenoic acid, the omega-6 fatty acid arachidonic acid, and other skin-friendly ingredients such as polysaccharides. Whether or not the entire red algae extract provides benefit when applied topically on skin is not known.

Portulaca oleracea extract. Extract that may have anti-inflammatory or analgesic properties.

potassium. Important element in diet that is present in such fruits as bananas and citrus. It is also an earth mineral that has absorbent properties and some disinfecting properties, but can also be a skin irritant.

potassium ascorbyl tocopheryl phosphate. Blend of vitamins C and E with phosphorus that functions as an antioxidant. See antioxidant.

potassium cetyl phosphate. Used as a detergent cleansing agent. See surfactant.

potassium hydroxide. Also known as lye, a highly alkaline ingredient used in small amounts in cosmetics to modulate the pH of a product. It is also used as a cleansing agent in some cleansers. In higher concentrations it is a significant skin irritant.

potassium myristate. Detergent cleansing agent that is a constituent of soap; it can be drying and sensitizing for some skin types. See surfactant.

PPG-12 buteth-16. Versatile ingredient composed of several non-volatile alcohols. Functions as a skin-conditioning agent, emulsifier, solvent, and surfactant.

PPG-14 butyl ether. Used as a hair- and skin-conditioning agent.

PPG-2 myristyl ether propionate. Mixture of glycols and fatty alcohols used as a skin-conditioning agent and, in some cases, as a thickening agent.

pregnenolone acetate. Precursor to other hormones, it can affect levels of progesterone and estrogen in the body when taken orally. When applied to skin it may work as a water-binding agent. There is no information about whether absorption through the skin is possible.

preservatives. Substances used in cosmetics to prevent bacterial and microbial contamination of products. While there is definitely a risk of irritation from these types of ingredients, the risk to skin and eyes from using a contaminated product is considered by many scientists to be even greater.

progesterone USP. A study published in the American Journal of Obstetrics and Gynecology (June 1999, pages 1504–1511) states that “In order to obtain the proper (effective) serum levels with use of a progesterone cream, the cream needs to have an adequate amount of progesterone in it [at least 30 milligrams per gram]. Many over the counter creams have little [for example, 5 milligrams per ounce] or none at all. The creams that are made from Mexican yams are not metabolized to progesterone by women. The cream used in the above study (Pro-Gest) contains pure United States Pharmacopoeia [USP] progesterone.” Dr. John Lee, author and longtime proponent of topically applied progesterone, explains that “The USP progesterone used for hormone replacement comes from plant fats and oils, usually a substance called diosgenin, which is extracted from a very specific type of wild yam that grows in Mexico, or from soybeans. In the laboratory, diosgenin is chemically synthesized into real human progesterone. Some companies are trying to sell … ‘wild yam extract’ [or other plant extracts] … claiming that the body will then convert it into hormones as needed. While we know this can be done in the laboratory, there is no evidence that this conversion takes place in the human body.” Dr. Lee is quick to explain that he doesn’t sell any of these products and receives no profit from their sale. He also does not recommend the use of natural progesterone creams with any other active hormones or herbs.

proline. See amino acid.

propolis. Brownish, resinous material that is collected by bees and used to construct the hive. It has antibacterial and anti-inflammatory properties for skin.

propylene carbonate. Liquid used as a solvent and film-forming agent. See film-forming agent.

propylene glycol. Along with other glycols and glycerol, this is a humectant or humidifying and delivery ingredient used in cosmetics.

propylene glycol stearate. Mixture of propylene glycol and stearic acid used as a skin-conditioning agent and emulsifier. S ee propylene glycol and stearic acid.

propylparaben. See parabens.

proteases. Enzymes that are part of a process that causes the breakdown of amino acids and proteins. There is research showing that proteases, when applied topically to skin, can reduce the visible scaling associated with dry, flaky skin. Whether proteases can be of benefit for wound healing when applied topically is unclear.

protein. Proteins are the fundamental components of all living cells and include a diverse range of biological substances, such as enzymes, hormones, and antibodies, that are necessary for the proper functioning of any organism, plant or animal.

Prunella vulgaris. See self-heal.

Prunus americana. See plum extract.

Prunus domestica seed extract. See plum extract.

Prunus dulcis. See almond oil.

Pseudopterogorgia elisabethae. See sea whip extract.

Pueraria lobata. See kudzu root.

pullulan. Glucan gum produced by black yeast that contains polysaccharides, which makes it a good water-binding agent, thickening agent, and antioxidant. See beta-glucan and mucopolysaccharide.

Pumpkin. Plant whose seeds are a rich source of fatty acids and several antioxidant components, including carotene, lutein, and various cartenoid pigments. Pumpkin oil is a rich source of the cell-communicating ingredient linoleic acid and antioxidant vitamin E. Pumpkin does not contain fragrance chemicals that are irritating to skin, and as such can be considered a beneficial plant ingredient. Enzymes naturally present in pumpkin are often claimed to be alternative exfoliant/peel ingredients for skin. There is no substantiated research supporting the efficacy of exfoliating skin with pumpkin enzymes. In all likelihood, the enzymes do not remain active or stable once they are added to a cosmetic product.

Punica granatum extract. See pomegranate extract.

purified water. See deionized water.

PVM/MA decadiene crosspolymer. Synthetic polymer used as a film-forming and thickening agent.

PVP. See polyvinylpyrrolidone.

PVP copolymer. See polyvinylpyrrolidone.

PVP/dimethylaminoethylmethacrylate. Polymer formed from PVP (polyvinylpyrrolidone) and the film-forming agent dimethylaminomethacrylate. See film-forming agent and polyvinylpyrrolidone.

pycnogenol. Antioxidant derived from the bark of the French Maritime pine tree. The term pycnogenol was previously used generically, but is now a U.S.-registered trademark. Only one company (Horphag Research, Ltd.) has access to this ingredient, and it is patent-protected.

pyridoxine hydrochloride (HCL). Scientific name for vitamin B6; may have antibacterial and antioxidant benefits for skin when applied topically.

Pyrus cydonia. See quince seed.

Pyrus malus. Species of apple; the pectin derived from it is used as a thickener in cosmetics.