EXPLAINER: What does makeup actually do to your skin?

Makeup is an everyday item for many people and non-negotiable for some. Is it bad for our skin? As always, the answer is not clear-cut and depends on the individual, their skin type, and the products they use.

With an overwhelming choice of cosmetic products available, most people don’t even know where to start with makeup. Organic? Natural? Fragrance free? Hypoallergenic? Non-comedogenic? Paraben free? What does this all mean, and are they any better?

The term makeup generally describes the group of cosmetics that are used for beautification. Other cosmetics include products that are used to cleanse, treat or protect the skin and hair.

These days, though, we commonly see all-in-one products, such as BB or CC creams, which combine makeup for coverage together with other ingredients to provide sun protection and skin benefits. Reducing the total number of products can be helpful for those with problematic skin, but may complicate things for some.

What does makeup do to our skin?

While in most cases makeup is harmless, certain products may cause problems for some individuals. It’s very important to use makeup and cosmetics that are suitable for your skin type or skin condition.

Skin types are broadly classified into four groups:

• oily – excess oil production, large pores, blackheads and acne prone

• sensitive – tight, stinging, intolerant to many products and prone to redness

• dry – dull, rough or flaky and prone to itchiness

• normal/combination – may be oily in the T-zone (forehead, nose and chin) but problem-free elsewhere

Although most people have a good idea of their basic skin type, they may fail to recognise the existence of an underlying skin disorder. Conditions such as eczema, contact dermatitis, rosacea and sun damage may cause inflammation and disruption of the skin barrier.

Inflammation causes itchiness or tenderness, redness, lumps and bumps, while barrier disruption results in tight, sensitive, dry and easily-irritated skin. These symptoms can be identical to those caused by reactions to cosmetics, and therefore should be considered before assuming makeup to be the cause. Conversely, an ongoing reaction to products being applied to the skin may explain why the skin is not responding to regular treatment.

Skin problems caused by cosmetics.

Acne cosmetica is a form of acne triggered by the use of certain cosmetic products. It is linked to certain ingredients that cause comedone formation (a blockage in the pore) and typically presents as small rash-like bumpy pimples. A common misconception is that the makeup physically blocks the pore, whereas actually the block is made of dead skin cells.

Mild inflammation results in excess skin turnover and clogging of the pore, with mineral oils being the most common culprit. It’s not always possible to determine makeup is the cause simply from the ingredient list, as it may be influenced by formulation, quantity and delivery methods.

Irritant dermatitis accounts for the majority of reactions to makeup and other cosmetic products. It can occur in anyone but is more likely in those with pre-existing sensitive skin or in those with underlying barrier disruption caused by a condition like eczema or rosacea. It typically causes an itchy, scaly red rash but can even blister or weep. Symptoms can occur immediately but may take weeks or even months to develop with weaker irritants, making it difficult to identify the cause.

Allergic contact dermatitis occurs when a person has become sensitised to an ingredient that has been applied to the skin. A red, itchy rash sometimes associated with swelling or blisters develops 12-48 hours after exposure, and may become chronic with ongoing use. The allergen can be very difficult to identify, because in some cases the product is used for months or years before sensitisation occurs.

Are there ingredients we should avoid?

Fragrances and preservatives are the most common cause of contact allergy resulting from cosmetics. There are over 5,000 different fragrances used in skin care products, many of which are natural plant extracts and essential oils.

Other common allergens include preservatives, lanolin, coconut diethanolamide (a foaming agent) and sunscreen agents. Preservatives, such as parabens, formaldehyde and Quaternium-15 are required in all liquid products to stabilise them and prevent the growth of microbes. A common misconception is that natural and organic ingredients will not cause allergy or irritation, but in prone individuals these can in fact be quite problematic.

Unless you have a known allergy or sensitivity, there are no specific ingredients that everyone should avoid. But looking for hypoallergenic, fragrance-free and non-comedogenic products is wise. Those with an oily skin type or a history of acne should also limit oil-based cosmetics.

Those with a sensitive or dry skin type, an underlying inflammatory skin condition or history of contact allergy should try to avoid irritants and potential allergens. Foaming agents, astringent products (such as toners that remove oils), scrubs and acids (such as alpha hydroxy acids used in acne and anti-ageing) tend to be irritating. Hypoallergenic formulations and those targeting sensitive skin are a good choice.

LISTEN: We asked Zoe Foster-Blake for her most coveted beauty advice for busy women (post continues after audio...)

What should I do if I think I might have a reaction?

If you develop a new rash or skin irritation, the first thing to do is to try to confirm the diagnosis. If you suspect you are reacting to one of your cosmetics but not sure which, then ideally you need to stop using all your current products in the problem area. You should try to simplify your daily routine, choosing products that have been specifically formulated for sensitive and allergic skin.

If the problem settles, you can reintroduce your cosmetics one at a time to see whether you can identify the culprit. It’s a good idea to test each one in a small localised area on the neck or face for a week or two before using it all over the face. This process is known as a “repeat open application test”.

If you can’t get to the bottom of it or find cosmetics that don’t irritate your skin, you may need to seek professional help to rule out other skin conditions and formally test for allergies if warranted.

This post originally appeared on The Conversation and was republished here with full permission.

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