Skincare Glossary

Acne is a common skin condition that is caused by hair follicles beneath the surface of the skin being unable to expel oil (sebum) and dead skin cells through the pores. As such, the oil and cells held beneath the skin's surface begin to grow bacteria within the follicle. This causes inflammation, resulting in redness, swelling, heat and pain. When the walls of the follicle break down, it expels the bacteria, cells and oil onto the skin's surface, creating lesions and pimples. Acne is most common in teens and young adults, but it can affect anyone, of any age.

An active ingredient is an element within a skincare formulation that is proven to benefit your skin in a specific way. Actives are incorporated to deliver meaningful results, and to help ensure products are truly doing what their labels tell us. They are helpful anywhere on your body or face where you have a specific skincare concern, actives are able to tackle roughness, dryness, pigmentation, blemishes and loss of elasticity. Common examples of active ingredients include amino acids, hyaluronic acid, vitamin C, and niacinamide.

Alkaline skincare is a formula that has a pH level of above 7. As our skin is naturally acidic (with a pH level of about 5.5), in general skincare products tend to be more acidic - helping to stimulate the skin to produce the elements it needs to stay healthy. Alkaline formulations may cause sensitization and allow bacteria to proliferate on the skin. There are emerging skincare brands that believe topical application of alkaline products can help stimulate the skin to ensure optimum cell function, however more research is needed in this area.

Antioxidants are naturally-occurring ingredients that protect against free radical-generating environmental aggressors (such as UV rays and pollution). An excess of free radicals in the skin can lead to inflammation and loss of collagen, resulting in dark spots, fine lines and wrinkles. Antioxidants neutralize free radicals, whilst offering a variety of other short-term benefits, depending on their type. Commonly found antioxidants in skincare include brightening vitamin C and strengthening vitamin E.

Cellulite is a very common condition where the skin develops a bumpy or dimpled appearance, most regularly on the thighs, hips, stomach and buttocks. It is a result of tension between the cords that connect the skin to the underlying muscle, and the fat cells that lie between. As the fat cells increase, they push upwards towards the skin, whilst the cords pull downwards towards the muscle, which creates an uneven appearance on the surface of the skin. The underlying causes of cellulite are not entirely clear, genetics, hormones, weight and muscle tone can all affect the development of cellulite. Cellulitis may appear on anyone, though it is particularly prevalent in women.

A chemical exfoliant is a friction-free formula that removes dead skin cells from the upper surface of the skin, allowing new skin cells to generate and resulting in more radiant skin. Chemical exfoliants work by dissolving the bonds that hold dead skin cells together (as opposed to a physical exfoliant, which manually buffs off dead cells from the skin's surface). There are three key families of chemical exfoliants: AHAs (potent acids that reduce fine lines and pigmentation whilst restoring radiance), PHAs (a gentler version that doesn't penetrate so deeply, and also works to attract moisture to the skin) and BHAs (a powerful oil-soluble exfoliant, able to travel slightly deeper into the pores to clear skin cells).

A chemical sunscreen contains ingredients that absorb and transform UVA and UVB rays into heat (as opposed to a mineral sunscreen, which creates a barrier to reflect UV rays).

Clinically proven is generally taken to mean the product in question has delivered evidence of desired results for a group of people during one or more clinical trials. This refers to effectiveness of the product only, and not safety (which is undertaken separately). However, guidelines surrounding the use of "clinically proven" vary region to region and are not bound by legislation.

Clinically tested means a product has been tested under clinical or laboratory conditions to accurately measure product claims in an unbiased setting.

Collagen is the most abundant protein found in the body, and it plays a vital role in providing strength and structure to our cells and tissues. There are 28 types of collagen, but Type 1 is the most prevalent, making up 90% of the collagen in our bodies and responsible for the structure of our skin, keeping it firm, supple and full and aiding in the regeneration of skin cells. As we mature, collagen production slows. You can restore collagen through skincare that includes ingredients that stimulate collagen production, ingestibles and lifestyle choices such as staying hydrated, following a healthy diet and avoiding environmental aggressors.

Comedones are small, skin-coloured bumps. A type of acne (comedonal acne), they are formed due to pores being blocked with oil, dead skin cells and bacteria. There are two main types of comedones: open comedones (blackheads) and closed comedones (whiteheads). This type of acne more commonly affects people with oily skin.

Whilst many think of dermatitis as a skin condition in itself, it is actually a general term for skin inflammation that makes skin appear dry, swollen, and discolored. There are several common types of dermatitis: atopic dermatitis (commonly referred to as eczema, and typically presenting as dry, rough, itchy skin that comes and goes) contact dermatitis (where contact with an irritant or allergen causes rashes that burn, itch, sting or blister), dyshidrotic dermatitis (characterized by small, itchy blisters, typically on the hands and the feet) and seborrheic dermatitis (dandruff).

Your skin is made up of three main layers: the epidermis, the dermis and the hypodermis. The dermis is the middle layer, and the thickest layer of skin. The dermis is rich in collagen and elastin, and is responsible for protecting your body from harm and producing oil to keep your skin hydrated, whilst also experiencing sensations such as pressure, heat, pain and cold. The dermis holds all your connective tissues, nerve endings, sweat glands and hair follicles.

Similar to collagen, elastin is a major protein within the skin that gives it elasticity - and is essential in ensuring skin tone and firmness, as well as aiding in the repair of scars and wounds. As with collagen, production of elastin slows as we age and is also affected by environmental aggressors such as UV exposure and pollution. However, creating new elastin is more challenging than creating collagen. As such, it's important to work to protect the elastin we already have within our skin. Wearing a broad spectrum SPF is the best way to preserve elastin, as well as considering antioxidant-rich products to fight against damage caused by free radicals.

Emollients soften dry, flaky skin by filling the spaces between dead skin cells with lipids (fatty substances that promote smoothness and softness). Emollients are typically found in moisturizers and help soften the skin, with the moisturizer's other ingredients attracting and locking hydration (see humectant and occlusive). Common emollients found in skincare are ceramides, squalane, lanolin, jojoba oil and shea butter.

An emulsifier is a substance that allows two or more ingredients that don't normally mix (for example oil and water) to combine, forming an emulsion. Emulsifiers work by reducing tension between liquids. Emulsifiers also enhance the absorption of certain skincare ingredients and may be helpful in prolonging absorption. Common emulsifiers include polysorbates, laureth-4, and potassium cetyl sulfate.

Your skin is made up of three main layers: the epidermis, the dermis and the hypodermis. The thin but strong epidermis forms the top layer of the skin and acts as the body's first line of defense, protecting against external aggressors such as UV rays, infection and pollution, whilst preventing loss of water and nutrients from our bodies. The epidermis varies in thickness depending on where it is on the body. The soles of your feet and the palms of your hands have the thickest epidermis, and the epidermis is thinnest on the eyelids.

An essence is a water-based skincare product containing potent active ingredients. Its role is to hydrate and nourish whilst preparing the skin to ensure that the products applied after it are well absorbed. Often confused with a toner or serum, an essence is distinct in that it does not perform a cleansing role (as per a toner) and doesn't target specific concerns outside hydration (as per a serum). An essence should be used post-cleansing routine, before application of your serum and / or moisturizer.

Essential oils are compounds extracted from plants to encapsulate their aromatic essence. Essential oils are obtained through distillation or cold pressing, and primarily used in skincare products for their fragrant properties, as inhaling essential oils stimulates the area of your brain that governs emotion, behavior and memory. Some essential oils have antioxidant benefits when applied on the skin, however it is important to note that many can irritate the skin causing dryness, redness or flaking.

There are two main categories of fragrance used in skincare: natural (extracted from their natural source, e.g. a fruit or plant) and synthetic (developed in a lab). Fragrance in skincare is often present as a pleasurable experience for the user, or to cover up potentially less pleasing smells. It is also important to note that "fragrance-free" and “unscented” are two different things. Fragrance-free means there are no masking scents within the product, whilst unscented may contain chemicals that mask any aromas. Those with a sensitivity to fragrance or an inflammatory skin condition (such as eczema or rosacea) should consider avoiding fragranced products.

Free radicals are unstable molecules, searching for other, healthy molecules to pair with and turn into an unstable molecule. Free radicals exist both within and outside the body, but exposure to external sources, such as UV rays and pollution, can cause an excess of unhealthy molecules which oxidize the skin cells, causing effects such as aging, pigmentation and dullness. Antioxidants can help protect your skin from free radical damage.

Humectants attract and retain ambient water with the skin, evenly distributing it within the skin to keep its water levels balanced, resulting in a smooth, dewy appearance. Common humectants include hyaluronic acid, amino acids, glycerin and panthenol. Humectants will generally form one part of a moisturizer, often combined with an emollient and / or an occlusive.

Hypoallergenic is a term used to describe a formulation that is less likely to cause an allergic reaction, through the elimination of common allergens or irritants. However, despite guidelines that products bearing the label should undergo allergenicity testing, there is no legally binding process undertaken before labeling a product hypoallergenic, which means it may not be allergy-proof. Always check the ingredient list, and if you suffer from sensitive skin, test the product on a small area before using it widely.

Hyperpigmentation refers to darker areas of skin and is caused by excess melanin (pigment). There are a number of types of hyperpigmentation including melasma, sun spots (freckles and solar lentigines), and post-inflammatory hyperpigmentation. Hyperpigmentation may be improved by topical treatments and prevention is also key such as by wearing a broad spectrum sunscreen and avoiding the sun during the hottest part of the day.

Hypopigmentation refers to lighter areas of skin and is caused by skin cells not producing enough pigment (melanin). The causes of hypopigmentation are numerous and include genetic factors (such as albinism), skin conditions such as vitiligo and post-inflammatory hypopigmentation (such as from dermatitis or psoriasis) or following an injury or burn. Treatment options for hypopigmentation are limited and will depend on the underlying cause.

Glycation occurs naturally in the body, and refers to the binding of sugar (such as glucose) to proteins within the skin (such as collagen and elastin), leading to the formation of advanced glycation end products (or AGEs). AGEs disrupt the collagen and elastin in our skin and contribute to the oxidation of skin cells, leading to signs of aging such as fine lines, dullness and pigmentation. Glycation is caused by a number of lifestyle factors (such as diet and UV exposure) and genetics, but also by age. As we age and the body produces less collagen, the skin becomes more susceptible to glycation. A balanced diet, exercise and a mindful approach to sugar can help prevent glycation. Antioxidants may also aid the reduction of oxidative stress associated with glycation.

Growth factors (also known as cytokines) are naturally occurring regulatory proteins that stimulate cell proliferation and differentiation, and wound healing. The purpose of growth factors in skincare is to act as a healing agent for the skin, they have been proven to boost collagen and elastin (both of which decline as we age), and are thought to strengthen and repair the skin barrier. Growth factors can be applied in topical form, and are generally well tolerated since they are based on proteins already found within the skin. Growth factors may be human-derived, synthetic or of plant, animal or bacterial origin.

Keratosis pilaris (KP) is a skin condition characterized by small, rough bumps on the skin, most commonly on the upper arms, thighs, cheeks or buttocks. KP is caused by a buildup of hair protein (keratin) within pores. Keratosis pilaris may also be itchy, dry and discolored. Keratosis pilaris can affect those of any age, but commonly worsens during puberty and improves over time. The cause is largely genetic, and KP may be associated with atopic dermatitis. There is no cure, but ensuring gentle exfoliation and moisturization is key to improving the skin's appearance.

A lipid is a naturally occuring fat within the skin that forms the link between cells and ensures water retention within the skin barrier. There are three types of skin lipids: ceramides (responsible for holding the skin's structure together and hydrating), cholesterol (improving skin elasticity), and fatty acids (maintaining balance in the skin barrier). Lipid production slows as we age, leading to dehydration and ultimately loss of elasticity and the appearance of fine lines and wrinkles. Lipids in skincare products help support the retention of moisture and prevent signs of aging. Look out for products that contain a mix of lipids and supplement with essential fatty acids in your diet (from foods such as salmon, trout, walnuts as well as chia and flax seeds) for best results.

Liposomes are small, spherical lipid vesicles that are utilized in skincare as a delivery system, containing active ingredients and releasing them once they have adequately penetrated the skin. Liposomes not only deliver the active ingredients within a product, but protect and ensure stability of them and other ingredients within the formula. These two facets together result in a product that is more potent and able to be delivered to the deeper layers of skin, ultimately delivering better results.

Melanin is a pigment found within our bodies that is responsible for skin tone and color, eye color, and hair color, as well as protecting us against harm from UV rays. There are two types of melanin that are responsible for pigmentation, eumelanin (associated with dark tones, such as brown and black) and pheomelanin (associated with reds and yellows). A person's melanin levels are primarily due to genetics, however the production of melanin is affected by UV exposure, age, hormones, inflammation and some skin disorders.

Melasma is a condition that causes hyperpigmented patches of skin, most typically occurring on the face in a symmetrical pattern and most commonly in women (however, it can appear anywhere on the body, and in men too). Whilst it is ultimately not entirely clear what exactly causes melasma, the condition is associated with estrogen and progesterone sensitivity, which means factors such as pregnancy, hormone therapy and oral contraceptives can trigger the condition, as well as other lifestyle factors such as sun exposure, blue light and heat. Melasma is also thought to be triggered by stress and thyroid disease. Those with darker skin types are more at risk than those with fair skin. You can help prevent melasma by certain topical treatments, avoiding sun exposure, wearing a broad-spectrum SPF and avoiding intense heat. Melasma may disappear on its own, but there are also topical products and procedures which can help lighten affected areas

Moles are a type of skin growth made up of pigment cells (melanocytes) that can develop on any area of the body. They often appear in childhood and adolescence, and both sun exposure and genetics play a role in their development. Moles can differ greatly in appearance - they may be small or large, flat or raised, smooth or wrinkled, tan, brown, black, red, pink or blue. The majority of moles are benign. Occasionally, moles may develop into melanoma, the most serious form of skin cancer. If you have new and/or changing moles, or moles that develop symptoms that you are concerned about (such as itching or bleeding) it is important to consult a healthcare professional.

Micellar water is a cleansing skin care product made using purified water, moisturizers and surfactants (compounds of water and oil). The molecules of these surfactants join together to form micelles, a chemical structure that attracts dirt and oil from the skin. Thanks to its formula, micellar water is a quick, effective yet gentle skin cleanser that is generally well tolerated.

The skin’s microbiome is a diverse community of trillions of microorganisms - such as bacteria, viruses and fungi - that are present on the surface of your skin. Your microbiome is essential to maintaining a healthy skin barrier as it helps reduce inflammation and protects you from infection. When unbalanced (a state that can be triggered by lifestyle and environmental factors, as well as factors like antibiotics and harsh skincare), it can lead to skin issues such as acne, psoriasis, eczema and aging. To keep your microbiome healthy, it is important to use gentle cleansers that will help protect the skin barrier, and to adequately hydrate your skin, both through topical forms of skincare and by drinking plenty of water.

Mineral sunscreen, also called physical sunscreen, creates a physical barrier on top of our skin, and reflects UV rays (as opposed to chemical sunscreen which contains ingredients that absorb and transform UVA and UVB rays into heat). Mineral sunscreens offer the most broad protection against UV rays (even protecting from UVA rays coming through windows) however they are not always as water and sweat resistant as chemical options, so you will need to apply regularly. Look for active ingredients like zinc oxide or titanium dioxide, but be aware that these can leave a white cast on the skin.

There is no set definition for what equates to “natural” skincare. Generally, it implies that the product in question is formulated with ingredients found in nature, often from plants, such as botanical oils. There are governing bodies (such as COSMOS and Soil Association) that offer certification that natural ingredients within products are grown without pesticides and suitably cultivated and harvested, but there is no regulation that states that products have to go through these governing bodies before calling themselves “natural”. In terms of efficacy, and how well natural products are tolerated by the skin, this varies greatly, naturally derived products can be highly effective when formulated properly, but irritants and allergens exist in nature too.

A non-comedogenic product is one that does not block pores, therefore reducing the chances of acne and pimples developing. Common non-comedogenic ingredients include niacinamide, aloe vera, vitamin E, vitamin C, witch hazel, allantoin and glycerin. With this said, there is no current regulation around labeling a product or ingredient "non-comedogenic".

Occlusives are a moisturizing ingredient that creates a barrier on top of your skin to prevent water loss. Occlusives help maintain skin hydration and prevent dryness, and tend to be found in moisturizers alongside humectants (working to attract moisture to the skin) and emollients (which smooth and soften the skin). Common occlusives include petrolatum, silicones, squalane, shea butter, beeswax and castor oil.

Organic skincare generally refers to products that include organically-farmed ingredients. As with natural skincare, there is no set global legislation around what can be labeled an organic skincare product, but there are local regulations for organic products in some regions, from governing bodies such as COSMOS and Soil Association. Whilst the definition of organic varies region to region, typically it means no laboratory made substances (such as pesticides, fertilizers, hormones, antibiotics, parabens) are used, and in some regions ingredients need to conserve biodiversity as well as improve air and soil quality.

Potential hydrogen (pH) refers to the acidity level of substances, on a scale ranging from 1 to 14, with 7 considered neutral. A healthy skin pH is more acidic, with levels ranging from 4-7, and the optimum level considered around 5. Your skin needs to have a certain level of acidity to combat potentially harmful free radicals and microbes. Your skin pH can be determined by at-home tests, seeing a dermatologist or careful observation, for instance, acne, inflammation and dry patches may be signs of a more alkaline profile. To help keep your skin balanced, it is important to choose mild, hydrating cleansers that maintain the skin’s pH balance.

A physical exfoliant uses texture to remove dead skin cells from the upper surface of the skin, allowing new skin cells to generate and resulting in more radiant skin. The removal of these skin cells is generally achieved through the use of beads, seeds or granules that create friction to loosen old cells, commonly within products such as cleansers or scrubs. Physical exfoliants are an alternative to chemical exfoliants, which work by dissolving the bonds that hold dead skin cells together.

Phytonutrients are natural chemicals or compounds produced by plants that give them their rich colors, and keep them healthy - protecting against the sun and harmful insects. Phytonutrients also have antioxidant and anti-inflammatory properties that help support healthy skin, promoting collagen production, fighting free radicals and improving cell function. Diet is important in ensuring you have adequate phytonutrients (the advice is to "eat a rainbow" of varied, colorful fruit and vegetables everyday), but phytonutrients are also present within skincare.

Plant stem cells are cells that naturally occur within plants, that are able to transform into various different cell types - essentially driving regeneration of the plant. The plant stem cells used within skincare, however, are not live cells - so they do not regenerate our skin as such, but they do contain extremely high levels of antioxidants and anti-inflammatories, which help protect our skin barrier and prevent aging. Due to their lab-cultivated nature, plant stem cells are pure and uncontaminated and have very little impact on the environment - using less water, and generating less waste than cultivation of the plants themselves.

To understand prebiotics you first need a brief understanding of probiotics. Probiotics are "good bacteria" - bacteria that are beneficial for your body. When there is an abundance of good bacteria, they can better keep harmful bacteria under control. Probiotics are important for your skin as they help keep your microbiome's community of microorganisms balanced, which is essential to maintaining a healthy skin barrier. Prebiotics are food for these bacteria, which stimulate their growth. Prebiotics can be taken in oral form (whether supplements or as part of your diet) or topically, via skincare products enriched with microbiome-nourishing prebiotics such as inulin, xylitol, oligosaccharides and rhamnose.

Probiotics are "good bacteria" - bacteria that are beneficial for your body. When there is an abundance of good bacteria, they can better keep harmful bacteria under control. Probiotics help keep your microbiome's community of microorganisms balanced, which is essential to maintaining a healthy skin barrier. Probiotic skincare is an emerging field focusing on introducing live beneficial bacteria to skincare. Research is ongoing, but many users report positive results, particularly those with sensitive or reactive skin. Ensuring you take an oral probiotic or eat foods naturally rich in probiotics (such as kefir, kombucha or kimchi) will help support your skin microbiome. Using prebiotic-enriched skincare (or taking an oral prebiotic) will also help probiotics flourish within your body.

Postbiotics are by-products secreted by live bacteria which help to support the good bacteria (or probiotics) on your skin and fight against bad bacteria - helping to keep your microbiome's community of microorganisms balanced, an essential part of maintaining a healthy skin barrier. Postbiotics are available as supplements and in topical form within some skincare products, however you can also stimulate production of postbiotics by eating prebiotic and probiotic rich foods. It’s been widely documented that postbiotic skincare is beneficial in calming inflammation.

Psoriasis is a skin condition characterized by flaky patches of skin which form scales, most regularly on elbows, knees, scalp and lower back. These patches might be itchy or sore, and in some cases pustules can develop. Psoriasis affects men and women of all ages, and is a long-term condition that tends to appear in cycles, and can have a profound impact on quality of life and a person's mental state. Psoriasis is caused by an increased production of skin cells, which build up to create the patches associated with the condition. It is not entirely clear what causes psoriasis, but it is thought to be due to immune and genetic factors, and psoriasis can appear following certain events or triggers. While there is no cure for psoriasis, there are many ways to help manage the symptoms, including topical skincare, oral and injectable medication and lifestyle factors such as diet.

Sebum is an oily, slightly waxy substance (mostly made from natural fats) that is produced by your body’s sebaceous glands to coat, moisturize and protect your skin. Sebaceous glands cover the majority of your body, but are most concentrated on the face. Sebum aids against water evaporation from the skin barrier, helps prevent bacteria from entering the skin and keeps the skin barrier healthy through UV protection, regulating the skin's pH balance and helping neutralize free radicals. The production of sebum is controlled by hormones - and can be affected by genetics - and under or overproduction of sebum can lead to dry or blemished skin. If you have excess levels of sebum, it can solidify and block your pores, leading to breakouts.