The glossary below lists skincare terms and definitions commonly used in articles, posts, and product explanations.
A
| Term | Definition | Aliases/ Abbreviations |
|---|---|---|
| Alpha-linolenic acid | Alpha-linolenic acid (ALA) is an omega-3 essential fatty acid known for its anti-inflammatory properties. It helps dry or damaged skin recover more quickly by accelerating the skin’s barrier repair processes. It also relieves itching, redness, and irritation of the skin. Plant oils high in ALA, like Rosehip Seed Oil, are nourishing yet lightweight, absorbing easily into the skin (Herb & Hedgerow Ltd, 2022). ALA is also found in Red Raspberry Seed Oil, Walnut Seed Oil, BlackberrySeed Oil, ChiaSeed Oil, and Flax Seed Oil (Susan M. Parker, 2014). | ALA |
| Arachidonic acid | Arachidonic acid (AA) is a saturated fatty acid that serves as a structural component in the phospholipids of epidermal keratinocyte membranes. In skincare, AA is typically used in low concentrations because it can induce both anti-inflammatory and pro-inflammatory responses (Herb & Hedgerow Ltd, 2022). | AA |
B
| Term | Definition | Aliases/ Abbreviations |
|---|---|---|
| Behenic acid | Behenic acid is a very long-chain fatty acid renowned for its exceptional stability. Initially discovered in moringa, it forms a protective shield against oxidative damage, helping to maintain the skin’s natural barrier. With its emollient and soothing properties, behenic acid effectively hydrates and calms dry, sensitive skin. Known for its dry, non-greasy feel, it imparts a similar texture to products containing this ingredient. It was found in Moringa Oil was used in Egypt for thousands of years and found in Egyptian tombs. Plant oils that contain Behenic acid include: Moringa oil, Praxci Oil, and Peanut Oil. |
C
| Term | Description | Aliases/ Abbreviations |
|---|---|---|
| Clinical trials | Clinical trials are prospective biomedical or behavioural studies on human participants designed to answer specific questions about biomedical or behavioural interventions, including new treatments (such as novel vaccines, drugs, dietary choices, dietary supplements, and medical devices) and known interventions that warrant further study and comparison (Wikipedia, 2024). | Research studies |
| Cold pressed | Cold pressing is a method that employs pressure to extract the most medicinally rich oils from plant matter without applying heat to the organic material. Cold pressing retains all the aroma and nutritional value – which is great for skincare products. | Cold pressing |
| Conjugated fatty acids | Conjugated fatty acids are unique polyunsaturated fats with a distinctive molecular structure. Unlike most fatty acids, their double bonds are positioned directly adjacent to each other, creating a rigid, linear shape. This structure contributes to their rich, thick texture, similar to that found in pomegranate oil, which is high in Punic acid, a type of conjugated fatty acid. Renowned for their skin benefits, conjugated fatty acids help rejuvenate skin cells, repair the skin’s protective barrier, and reduce inflammation. They improve skin tone, hydration, and elasticity while also promoting a brighter complexion. | |
| Conjugated linoleic acid | Conjugated linoleic acid (CLA) is the most well-known member of this family, primarily found in animal sources. It’s recognised for its anti-inflammatory properties and ability to improve the appearance of sun-damaged skin. | CLA |
| Conjugated linolenic acids | Conjugated linolenic acids (CLNAs) are another group of conjugated fatty acids with potent antioxidant and anti-inflammatory effects. They stimulate skin cell renewal and enhance skin elasticity. – Punicic acid, found in pomegranates, is the plant world’s top source of CLnA. It is also found in snake and bitter gourd seeds. – Eleostearic acid: found in pomegranate seed oil and cherry kernel oils, is also a CLnA. – Calendic acid: (alpha- and beta-calendic acids) from pot marigold (the seed oil, not the macerate) is another botanical source of CLnA. | CLnAs |
| Comedones | Comedones (from comedo) are small, flesh-coloured, white, or dark bumps that give skin a rough texture. The bumps are one type of acne. They are found at the opening of skin pores where a solid core can often be seen in the middle of the small bump. Comedones are called open or closed based on whether the surface is disrupted (open) or intact (closed). Open comedones are blackheads and closed comedones are whiteheads (MedicinePlus, 2022). |
E
| Term | Definition | Aliases/ Abbreviations |
|---|---|---|
| Erucic acid | Erucic acid is a unique very long-chain fatty acid composed of 22 carbon atoms. These longer fatty acid chains excel at preventing moisture loss from the skin, creating a protective barrier. Rich in erucic acid, oils offer a distinctive, silky feel without greasiness, akin to silicone. This fatty acid is exceptionally stable, maintaining its protective function against oxidative damage. Plant oils containing Erucic acid include: Meadowfoam Seed Oil, Abyssinian Oil, Broccoli Seed Oil, and Diakon Radish Seed Oil (Susan M. Parker, 2014). | Docosenoic acid |
| Essential fatty acid | Essential fatty acids (EFAs) are types of polyunsaturated fats that the human body cannot produce on its own. Despite being fats, they are crucial for overall health and well-being. They play a vital role in various bodily functions, including brain function, heart health, skin health, and immune system regulation. They help build cell membranes, produce hormones, and regulate blood pressure. There are two main types of EFAs: – Omega-3 fatty acids: Found primarily in fatty fish, flaxseed, and chia seeds. – Omega-6 fatty acids: Found in vegetable oils, nuts, and seeds. While both are essential, modern diets often contain too much omega-6 and not enough omega-3, leading to an imbalance (Herb & Hedgerow Ltd, 2022). | EFA |
F
| Term | Definition | Aliases/ Abbreviations |
|---|---|---|
| Food Grade | Food grade (FG) means it’s safe for human consumption and/or exposure. | FG |
| Free Radicals | An atom, molecule or ion that has unpaired electrons. In general, these unpaired electrons make free radicals highly chemically reactive towards other substances, or even towards themselves. Free radicals have somehow lost an electron. They can be formed during normal bodily functions such as when cells burn food for energy or even when the body is fighting off bacteria or viruses. Free radicals in general are not dangerous. But when our cells are exposed to pollution, radiation, cigarette smoke or certain chemicals, this process creates a larger quantity of free radicals in the body: a surplus of unbalanced cells looking to become balanced by scavenging for electrons. They will actually “steal” electrons from balanced cells and set off a chain reaction of damage. If there are no electrons available, or if free radical production is in excess, damage occurs and creates an environment of oxidative stress. (Herb & Hedgerow Ltd. 2016.) |
G
| Term | Definition | Aliases/ Abbreviations |
|---|---|---|
| Gadoleic acid | Gadoleic acid is a very long-chain fatty acid and a vital component in safeguarding the skin’s protective barrier. Primarily found in Jojoba Oil and Meadowfoam Seed Oil, its unique structure contributes to the exceptional stability of these oils. By shielding the skin’s outer layers from oxidative damage, gadoleic acid helps maintain a healthy and resilient complexion. | Eicosenoic acid |
| Gamma-linoleic acid | Gamma-linoleic acid (GLA) is an omega-6 essential fatty acid found in small quantities in our skin’s ceramides. It has powerful anti-inflammatory and wound-healing properties, making it particularly beneficial for mature ageing skin. It can soothe redness, itching and irritation. GLA helps maintain moisture levels and supports the skin barrier function. GLA is also effective for dry and acne-prone skin. Plant oils rich in GLA, like Borage Seed Oil, absorb quickly, deeply nourishing the skin without leaving it oily (Herb & Hedgerow Ltd, 2022)(Susan M. Parker, 2014). GLA is also found in Evening Primrose Oil and Black Currant Seed Oil (Susan M. Parker, 2014). | GLA |
H
| Term | Definition | Aliases/ Abbreviations |
|---|---|---|
| Hexane | Hexanes are used in the formulation of glues for shoes, leather products, and roofing, and are obtained by refining crude oil (petrochemicals). We don’t want petrochemicals near our skin. | |
| Hyperpigmentation | Hyperpigmentation is a term for skin that appears darker due to excess melanin production. |
L
| Term | Definition | Aliases/ Abbreviations |
|---|---|---|
| Lauric acid | Lauric acid is a medium-chained fatty acid naturally found in our skin’s sebum, making it highly compatible with normal skin functions. Primarily recognised for its potent antimicrobial properties, it helps defend the skin against harmful bacteria. Plant oils high in Lauric acid are: Coconut oil, Palm Kernel Oil, Babassu Butter, and other tropical oils (Susan M. Parker, 2014). | |
| Linoleic acid | Linoleic acid (LA) is an omega-6 essential fatty acid is particularly important for skin health, and which the body cannot produce itself. It plays a key role in maintaining the integrity of the skin barrier function and reducing the production of collagenase, an enzyme that breaks down collagen in the skin. Oils rich in linoleic acid absorb quickly and easily into the skin. LA has shown regenerative and anti-inflammatory properties. For oily and acne-prone skin, it can improve sebaceous gland function and help prevent acne. Plant oils high in linoleic acid, like Evening Primrose Oil, Grape Seed Oil and Rosehip Seed Oil, have been shown to boost ceramide production, enhancing the skin’s lipid barrier (Herb & Hedgerow Ltd, 2022). LA is also found in Safflower Seed Oil and Passion Fruit Seed Oil (Susan M. Parker, 2014). Note: When linoleic acid is deficient in the skin, oleic acid and other monounsaturated fatty acids can make problem skin worse by increasing sebum production, causing congested skin and comedones. Minimal use of monounsaturated fatty acids is recommended until the skin’s health is restored (Herb & Hedgerow Ltd, 2022)(Susan M. Parker, 2014). | LA |
M
| Term | Definition | Aliases/ Abbreviations |
|---|---|---|
| Monounsaturated fatty acid | Monounsaturated fatty acids (MUFAs) are some of the most commonly found in nature and are typically liquid at room temperature. MUFAs have anti-inflammatory properties and can even help with weight control. Sources of MUFAs: Olive oil, Avocados, Nuts (almonds, cashews, pecans), Seeds (chia, flaxseed). MUFAs are considered healthy fat and are often recommended as part of a balanced diet. | MUFA |
| Myristic acid | Myristic acid is a saturated fatty acid and powerful ingredient with both anti-inflammatory and regenerative properties. It helps strengthen the skin’s protective barrier, promoting healing and renewal. Easily absorbed, it also provides a delicate layer of protection. Myristic acid, along with Myristoleic acid, were both identified and named for Myristica fragrans, the botanical name of the Nutmeg tree. Plant Oils that contain myristic acid include: Tamanu Oil / Foraha Oil, Palm Oil and Palm Kernel Oil (Susan M. Parker, 2014). |
N
| Term | Definition | Aliases/ Abbreviations |
|---|---|---|
| Natural | Natural ingredients are obtained only from plants, animals, micro-organisms or minerals. Ingredients obtained from fossil fuels (petrochemicals) are excluded from the definition (International Organisation for Standardisation (ISO), 2016). These natural ingredients all have naturally occurring rich nutrients in a bioavailable state. They are often preferred for their gentle and nourishing properties, but they can be more expensive and less stable (e.g. shorter shelf-life). |
O
| Term | Definition | Aliases/ Abbreviations |
|---|---|---|
| Oleic acid | Oleic acid is a beneficial omega-9 monounsaturated fatty acid readily absorbed by the skin. It helps maintain suppleness, flexibility, and softness of the skin. Oleic acid is highly compatible with the sebum and lipids of the stratum corneum and carries nutrients deeply into the skin layers. It has moisturising, anti-inflammatory, and regenerative properties. Oleic acid is found in Olive, Avocado, Camellia, Hazelnut, and Macadamia oil (Susan M. Parker, 2014). Oleic acid typically improves skin condition, however, when used undiluted in high concentrations, it can act as a penetration enhancer, potentially disrupting the skin’s natural barrier and leading to dryness. Note: When linoleic acid is deficient in the skin, oleic acid and other monounsaturated fatty acids can make problem skin worse by increasing sebum production, causing congested skin and comedones. Minimal use of monounsaturated fatty acids is recommended until the skin’s health is restored (Herb & Hedgerow Ltd, 2022)(Susan M. Parker, 2014). | |
| Organic | Organic ingredients are natural ingredients originating from organic farming methods or from wild harvesting in compliance with national legislation or equivalent International Standards where applicable (International Organisation for Standardisation (ISO), 2016). An organic cosmetic must contain a certain percentage of ingredients originating from organic farming, with at least 95% of ingredients capable of being organic (Cosmébio, 2019). | |
| Oxidation | The loss of electrons by a molecule, atom or ion. Oxidation can also mean the gain of oxygen or the loss of hydrogen. | |
| Oxidative stress | While free radicals and antioxidants are part of your body’s natural and healthy functioning, oxidative stress occurs when free radicals and antioxidants are out of balance. Oxidative stress can cause damage to many of your tissues, which can lead to a number of diseases over time. (Megan Dix, RN, BSN, 2024) |
P
| Term | Definition | Aliases/ Abbreviations |
|---|---|---|
| Palmitic acid | Palmitic acid is a naturally occurring saturated fatty acid found in our skin’s sebum. Found in high percentages in plant butters and heavier plant oils. It was first discovered in palm oil and thus the palm in its name. Palmitic acid has antimicrobial properties which act as a protective barrier, helping the skin to retain moisture. It is also said to cause cancerous cells to self-destruct, and studies have observed it retarding cell proliferation (Susan M. Parker, 2014). | |
| Palmitoleic acid | Palmitoleic acid is an omega-7 monounsaturated fatty acid. It was discovered in palm oil and thus the palm in its name. Palmitoleic acid is a natural component of skin produced by the sebaceous glands and acts as a protective barrier with antimicrobial properties. As we age, palmitoleic acid production declines, making it a valuable ingredient for mature skin care. Its antimicrobial benefits help prevent skin damage from minor injuries and support the healing process. Palmitoleic acid maintains mucus membrane health and is able to protect the skin against sun damage (Herb & Hedgerow Ltd, 2022)(Susan M. Parker, 2014). Plant oils that contain palmitoleic acid are: Macadamia Nut Oil, Sea Buckthorn Berry Oil, Chilean Hazelnut Oil, and in small quantities in many others (Susan M. Parker, 2014). | |
| Petrochemicals | Petrochemicals are carcinogenetic (think crude oil, microplastic particles). They contain cancer-causing properties and have also been linked to reproductive toxicity, premature ageing, reduced cell development, poor skin function and respiratory dysfunction (Oland, 2022). We want to stay away from anything made from/processed by petrochemicals | |
| Phenols and Polyphenols | Phenols are compounds containing one or more hydroxyl groups attached to an aromatic ring. These compounds are further categorised into simple phenols and polyphenols, based on the number of phenol units present. Many vegetable oils contain valuable phenolic compounds, including: – Phenylpropanoids: Such as ferulic and caffeic acids, these compounds are potent antioxidants that protect the skin from damage. – Flavonoids: Known for their anti-inflammatory and antimicrobial properties, flavonoids also shield the skin from free radicals. – Tannins: The most abundant polyphenols, tannins impart a dry, astringent feel to oils rich in these compounds, like hazelnut and camellia oils. They play a crucial role in the oil’s overall properties. | |
| Photostable | When an ingredient is photostable, it is resistant to change under the influence of radiant energy and especially of light (Merriam-Webster). This is good because these ingredients are safe to use in sunlight, as opposed to phototoxic ingredients (see below). | |
| Phototoxic | When an ingredient is phototoxic, it renders the skin susceptible to damage (such as sunburn or blisters) upon exposure to light especially ultraviolet light. It can also cause skin damage in the form of sunspots (aka. liver spots) and pigmentation. Phototoxicity occurs in anyone exposed to sufficient doses of a phototoxic agent and UV radiation; it usually manifests as an exaggerated sunburn reaction (Henry W. Lim, 2019). | |
| Phytosterols | Phytosterols are a subgroup of triterpenoids, a vast and diverse family of compounds. These plant-based substances share a similar structure to cholesterol and are essential components of plant cell membranes. In skincare, phytosterols are prized for their ability to strengthen the skin’s barrier and improve elasticity. Key phytosterols include beta-sitosterol, campesterol, and stigmasterol. These compounds offer a range of benefits, including antioxidant, anti-ageing, and anti-inflammatory properties. | Triterpenoids |
| Punicic acid | Punicic acid is an omega-5 fatty acid concentrated in Pomegranate Seed Oil. Its unique structure gives pomegranate oil a rich, thick texture despite its unsaturated nature. This fatty acid acts as a protective barrier, preserving the skin’s moisture while shielding it from environmental aggressors. Additionally, oils high in punicic acid support skin health by boosting collagen production and defending against sun and weather damage. Particularly good for mature skincare. |
R
| Term | Definition | Aliases/ Abbreviations |
|---|---|---|
| Ricinoleic acid | Ricinoleic acid is a unique omega-9 monounsaturated fatty acid that constitutes the majority of Castor Seed Oil. It has antifungal, antibacterial healing, and pain-alleviating properties. Ricinoleic acid has the ability to deeply penetrate the skin. It has high viscosity and fluidity, and imparts humectant qualities, making it an effective moisturiser that can help alleviate dry skin conditions. Castor Seed Oil can thicken and regenerate skin tissues, helping preserve the integrity of mature skin and damaged complexions. As a humectant, it attracts moisture to it and the skin. (Susan M. Parker, 2014) (Susan M. Parker, 2014) | |
| Redox | The contraction of the name for chemical reduction-oxidation reaction. Redox reactions are reactions in which there’s a simultaneous transfer of electrons from one chemical species to another. They are therefore really composed of two different reactions: oxidation (a loss of electrons) and reduction (a gain of electrons) see below. | |
| Reduction | The gain of electrons by a molecule, atom or ion. |
S
| Term | Definition | Aliases/ Abbreviations |
|---|---|---|
| Saturated fatty acid | Saturated fatty acids function as barrier lipids. They are occlusive and protective, coating the skin and absorbing slowly. They are excellent protection against harsh elements, wind, cold, sun, and dryness (Susan M. Parker, 2014). They are solid at room temperature and why butter, lard, and coconut oil is solid. Commonly found in animal products like Meat, dairy, and poultry. Some plant-based sources include Coconut oil, Palm oil, and Cocoa butter. For many years, saturated fats were considered unhealthy due to their link to heart disease. However, more recent research has shown that the picture is more complex (Herb & Hedgerow Ltd, 2022). | |
| Skin barrier function | The skin barrier and passage functions must be able to absorb or repel what the skin needs for optimum health. When these functions are working properly, harmful bacteria, chemicals, and dirt are kept out. Also, moisture, nutrients, and fatty acids can be absorbed into the skin’s layers. Linoleic acid plays an important role in maintaining the barrier and passage functions (Susan M. Parker, 2014). | |
| Sodium lauryl sulphate | Sodium Lauryl Sulphate (SLS), amongst other health risks, can clog pores causing acne for people with sensitive skin. These ingredients, usually synthetic and made from petrochemicals, can remove protective oils from the surface of the skin, leaving it susceptible to dryness, inflammation and short-term damage (Jillian Levy, 2022). | SLS, Sodium Dodecyl Sulfate (SDS), Sodium Laureth Sulfate (SLES) |
| Squalene peroxidization | Squalene peroxidization is one of the responsible factors for the formation of comedones and inflammatory lesions (PubMed, 2023). Squalene peroxides promote acne, roughening of skin, wrinkling & pigmentation | |
| Stearic acid | Stearic acid is a naturally occurring long-chain saturated fatty acid found in the skin’s oil. Known for its solid texture, it contributes to the firmness of butter and the thickness of certain oils. This saturated fatty acid is a valuable ingredient in skincare, providing a protective barrier to help maintain skin health. | |
| Synthetic | Synthetic ingredients are made by chemical synthesis, especially to imitate a natural product (Oxford Dictionary). They are more cost-effective than natural ingredients and have a longer shelf life, but they may not be gentle or beneficial for the skin. Not all synthetic ingredients are bad, but some come from various questionable sources, including petroleum and petrochemicals. |
T
| Term | Definition | Aliases/ Abbreviations |
|---|---|---|
| Terpenes and Terpenoids | Terpenes are a vast family of compounds built from isoprene units, five-carbon molecules. Terpenoids are modified terpenes that incorporate oxygen. Together, they form one of the largest groups of plant compounds, with over 20,000 identified structures. While primarily found in essential oils, they also occur in vegetable oils. There are hundreds of carotenoids, including beta-carotene, alpha-carotene, lutein, zeaxanthin, lycopene, and astaxanthin. Many, but not all, are precursors to vitamin A. In skin care, carotenoids offer photoprotection, antioxidant, and anti-inflammatory benefit | Triterpenes Tetraterpenes |
| Triterpenes | Triterpenes, such as squalene, are a key component of many oils. Squalane, the hydrogenated form of squalene, is a widely used, lightweight emollient. | |
| Tetraterpenes | Tetraterpenes are often found as carotenoids in plant oils. These pigments, responsible for the vibrant red, orange, and yellow hues in fruits and vegetables, are potent antioxidants. | |
| Transepidermal water loss | Transepidermal water loss (TEWL or TWL) is the loss of water that passes from inside a body (animal or plant) through the epidermis to the surrounding atmosphere through diffusion and evaporation processes (Wikipedia, 2023). | TEWL, TWL |
V
| Term | Definition | Aliases/ Abbreviations |
|---|---|---|
| Very long-chain fatty acids | Very long-chain fatty acids play an important role in lipid balance and are critical for skin health. Plant oils that contain these are: Jojoba Oil and Meadowfoam Seed Oil, Abyssinian Oil, Broccoli Seed Oil, and Diakon Radish Seed Oil. Unfortunately, Canola or Rapeseed oil is mostly genetically modified (GMO) these days and have had the fatty acids bred out of them. (Susan M. Parker, 2014) | |
| Vitamin E | Vitamin E is a collective term for a group of fat-soluble antioxidants that safeguard cells and fatty acids from oxidative damage. This family comprises tocopherols (alpha, beta, gamma, and delta) and tocotrienols (alpha, beta, gamma, and delta). Naturally occurring in various vegetable oils, alpha-tocopherol is the most recognized form for its biological activity, while gamma-tocopherol excels at preserving product stability. Synthetic vitamin E, such as tocopheryl acetate, is also available. While offering enhanced stability, it possesses lower antioxidant activity compared to its natural counterpart. Although tocopheryl acetate can be converted into an active form upon skin application, it primarily functions as a skin antioxidant rather than a product preservative. | Tocopherols Tocotrienols |
XYZ
| Term | Definition | Aliases/ Abbreviations |
|---|---|---|
| More terms still to come |
References
Cosmébio, 2019. Natural vs Organic Cosmetics: What’s the difference?
Herb & Hedgerow Ltd. 2016. Physiology of Dermal Ageing
Herb & Hedgerow Ltd. 2022. Carrier Oils Handbook.
Henry W. Lim, 2019. Fitzpatrick’s Dermatology, 9e, Chapter 97: Phototoxicity and Photoallergy.
International Organisation for Standardisation (ISO), 2016. Guidelines on technical definitions and criteria for natural and organic cosmetic ingredients and products.
Jillian Levy, 2022. What Is Sodium Lauryl Sulfate? Where It’s Found + Risks.
Megan Dix, RN, BSN — Updated on February 19, 2024. Medically reviewed by Adam Bernstein, MD, ScD
MedicinePlus, 2022. Comedones.
Oland, 2022. The Lowdown on Petrochemicals in Beauty Products.
PubMed, 2023. Squalene Peroxidation and Biophysical Parameters in Acne-Prone Skin: A Pilot “In Vivo” Study.
Susan M. Parker, 2014. Power of the Seed.
Wikipedia, 2023. Transepidermal water loss.
Wikipedia, 2024. Clinical Trials.