A-Z skincare ingredient cheat sheet

Here is your go-to cheat sheet of skincare ingredients – this post should help you identify and learn the role of some key ingredients in skincare products.


Aka alpha hydroxy acid, a chemical exfoliant. These compounds are water-soluble acids that help get rid of dead skin cells.


Aka a type of vitamin E (see below).


Antioxidants protect cells from the damaging effects of free radicals. Free radicals are reactive species which damage cells and might contribute to the development of cardiovascular disease and cancer. The body can be exposed to free radicals from environmental exposures (as well as intrinsic exposures), such as cigarette smoke, air pollution, and ultraviolet radiation from the sun. Antioxidants might protect cells from the damaging effects of free radicals; a lot of skincare products aim to protect the skin from environmental exposures of free radicals.[1]

Ascorbic Acid

Aka vitamin C (see below).


Avobenzone is a common, synthetic UVA-filter in suncreens; this is due to its ability to absorb ultraviolet light over a wide range of wavelengths compared to other sunscreen ingredients. Unfortunately, it is known to be photounstable – when irradiated with UVA light avobenzone partially degrades thus reducing its photoprotective effects. Whilst avobenzone itself is a relatively safe compound, its degradation products (especially those with unknown toxicology) have the potential to be harmful, causing deleterious effects. There has been evidence to suggest that when used in conjunction with antioxidants (if, for example the formulation utilises them) the photostabilisation of avobenzone can be increased.[2]

Azelaic Acid

Azelaic acid is FDA-approved for treating acne and rosacea. In addition to this, it is also know to reduce hyperpigmentation, melasma and acne scars.


You’ve probably heard bakuchiol being discussed in the context of retinol – i.e. that it’s a great alternative to it. You may have heard bakuchiol has all the anti-ageing perks of retinol but manages to avoid the irritation that can come with the use of one. Bakuchiol is a promising alternative to retinol (and other retinoids), especially if you suffer with skin sensitivity. The effectiveness (and mode of action) of bakuchiol requires further study since there is simply not enough research out there. Although seemingly safe, bakuchiol requires more vigorous safety studies (especially for pregnant women). Additionally, its anti-oxidant and anti-microbial properties means extra perks compared to retinol so perhaps its worth a try – no need to ditch your retinoids – thus far, evidence shows it is safe to use them both in conjunction (and retinoids might perform even better when doing so).

Benzoyl Peroxide

Benzoyl peroxide is a common acne-fighting ingredient – it inhibits the growth of the bacteria (p.acnes) that causes acne. It also reduces excess oil on the skin and removes dead cells that can clog pores which may also help with acne.


β-glucans form apart of the cell walls of bacteria, fungi, yeast, and cereals such as oat and barley. These highly hygroscopic (water loving) polysaccharides attract and hold water, providing a plumping effect similar to hyaluronic acid. Although there is quite a bit of anecdotal evidence that beta-glucan is ‘better’ than hyaluronic acid, there are very few scientific studies confirming this.


Aka beta hydroxy acid, another chemical exfoliant. These compounds differ to AHAs in the fact that they are often oil soluble rather than water soluble, making them suitable for oily-prone skin.


Aka butylated hydroxytoluene. This antioxidant is often used to preserve skincare products.


Should we leave caffeine where it belongs, in our morning cup of coffee? Well, perhaps not – this molecule reduce wrinkles, brighten skin, and gets rid of inflammation. This molecule also possesses antioxidant properties.[3]

Capric Triglyceride

Capric triglyceride is usually made from combining coconut oil with glycerin. This triglyceride is primarily used for formulation purposes, it turns out its a great emulsifier. There are other perks which include its ability to hydrate the skin and it is also an antioxidant.


Ceramides is an umbrella term for a family of waxy lipid molecules. Ceramide is the main component of the stratum corneum of the epidermis layer of human skin; ceramides help to increase the barrier function of the skin and improve moisture retention. With age there is a decline in ceramide in the skin, thus a ceramide-containing product may help to combat this. A clinical trial had participants use a ceramide-rich wheat extract which saw an increase in skin hydration for participants using the extract rather than the placebo.[4]

Coenzyme Q10

Coenzyme Q10 is used in many skincare products as the active ingredient; it is known to reduce oxidative stress in the skin and may help improve the signs of ageing.


Dimethicone is a type of silicone. This generally inert silicone-based polymer is used widely in skin-moisturizing lotions – essentially for its sensory properties.


Glycerin/glycerol is a humectant, a type of moisturising agent that pulls water into the outer layer of your skin. Technically, glycerol is the true name of the humectant, whereas glycerine is actually the commercial name of glycerol, when it is not pure. Glycerin contains approximately 95% of glycerol.

Glycolic Acid

This is an example of an AHA (see above for more info on AHAs). In addition to its exfoliant properties, glycolic acid is also known to stimulate fibroblasts to produce collagen.

Hyaluronic Acid

Hyaluronic Acid (HA) occurs naturally in the skin – this molecule increases hydration in the skin, helping it to appear plumper and more hydrated. HA can be found bound to collagen on one side and links to water molecules on the other, providing that plump effect we see, thus reducing the appearance of fine lines and wrinkles. As we age we lose collagen and hyaluronic acid, making the skin dehydrate more easily.


Hydroquinone decreases the production of melanin and is thus found in skin-lightening creams.

Lactic Acid

Another example of an AHA.


Niacinamide is a form of vitamin B₃. This compound is known to be a bit of an all-rounder; its an anti-inflammatory, helps with oil regulation, strengthens the skin barrier function and it also enhances ceramide production. It also helps to minimise fine lines and wrinkles.


Peptides are short chains of amino acids – essentially, the building blocks of life. Many synthetic peptides have been developed for use in collagen stimulation, wound healing, “Botox-like” wrinkle smoothing, as well as antioxidative, antimicrobial and whitening effects. A popular peptide being palmitoyl pentapeptide-4, which can reduce fine lines, wrinkles and improve skin texture significantly.[5]


Aka Petroleum jelly, is a mixture of hydrocarbons which is often exploited for its moisturising properties – its known as an occlusive i.e. it forms a protective layer on the surface of your skin, preventing moisture loss.


Aka polyhydroxy acids. You guessed it, a chemical exfoliant. Gluconolactone is a popular commercial PHA used in skincare products, delivering similar anti-ageing benefits as the other hydroxy acids. PHAs tend to be pretty gentle exfoliators.

Retinoic acid

The vitamin A derivative that is responsible for the reduction in fine lines and acne, cell renewal and collagen production.


Retinoid is used as an umbrella term for any compound derived from vitamin A (a vitamin A derivative). A vitamin A derivative possesses structural or functional similarities to vitamin A, but is not quite vitamin A. In some contexts, the term retinoid can also refer to prescription-strength vitamin A derivatives (such as tretinoin and tazarotene). Examples of retinoids include retinal (aka retinyladehyde or retinaldehyde), adapalene, retinoic acid, retinyl esters (such as retinyl propionate and retinyl palmitate), tretinoin and tazarotene etc. Retinoids require conversion to retinoic acid by the skin to produce clinical effect.


Aka vitamin A. Despite being the most popular vitamin A species present in anti-ageing skincare products, retinol still requires conversion to retinoic acid by the skin to produce effect. See my retinoid vs retinol post for a more in depth comparison of them both.


Resveratrol is an antioxidant found in the likes of grape skin.

Salicylic Acid

This is an example of a BHA (see above for more info on BHAs).


Both squalene and squalane serve a similar purpose – these fats help to keep the skin moisturised. So what’s the difference? Squalene is naturally produced by the body, however if we want to apply extra squalene topically then there is a small issue: it’s not the most stable compound in the world. This is where squalane comes in – this compound is a much more stable analogue of squalene and is thus more commonly found in skincare products.

Titanium Dioxide

Titanium dioxide is an example of a physical sunscreen – nanosized titanium dioxide is often used because of its strong UV-light absorbing capabilities.

Vitamin C (Ascorbic Acid)

Vitamin C is the most prevalent antioxidant already present in our skin. It is also required for collagen production and has use in the reduction of fine lines.

Vitamin E

There are several forms of Vitamin E, each with varying levels of biological activity. This class of compounds show antioxidant behaviour and alpha-Tocopherol is the only form that is recognised to meet human requirements.[1] In addition, vitamin E has moisturising properties and helps to strengthen the skin barrier function.

Zinc Oxide

Zinc oxide is another physical sunscreen. As to whether zinc oxide or titanium dioxide is a better physical sunscreen – titanium dioxide is more effective in the UVB range and zinc oxide in the UVA range. A combination of the two assures a broad-band UV protection.[6]

This isn’t a fully comprehensive list so please leave a comment if there is an ingredient I’ve missed that you would like to see on here!