Plumping lip gloss: how it works, what is real and who should skip it

The tingle sells the product. A plumping gloss that stings feels as if it is doing something, and for a short while it is: blood comes to the surface, the lip swells slightly and the colour deepens. The effect is real, small and gone within hours. A second group of plumpers skips the sting and works by hydration, which is gentler and also temporary.

Knowing which type is in the tube matters for anyone with sensitive skin, cracked lips or eczema, because the ingredients that cause the tingle are the same ones dermatologists tell people with chapped lips to avoid.

How does a plumping lip gloss work?

A plumping lip gloss is a gloss that makes lips look temporarily fuller by one of two mechanisms. The first is irritation. Ingredients such as menthol, capsicum extract, cinnamon oil, ginger and methyl nicotinate irritate the surface, the body responds by sending more blood to the area, and the lip swells a little. Dermatologist Elaine F. Kung describes this as a mild and brief plumping caused by transient swelling (Yahoo Health). Cosmetic chemists describe the same process as a temporary mild irritation of the lips (Makeup.com).

The second mechanism is hydration. Humectants such as hyaluronic acid (sodium hyaluronate) and polyglutamic acid bind water at the lip surface, so the skin looks smoother and fine lines fill in. There is no sting. Brands add peptides to these formulas for a collagen-support claim. The industry is moving toward this second group, and the peptide claim has spread from Rhode at US$16 to Essence at €2.99 (LINDA.nl).

On top of both mechanisms, the gloss itself makes lips look fuller by reflection. A shiny surface reads as rounder than a matte one. Some of what a plumper appears to do is what any gloss does.

Which ingredients cause the tingle?

The table lists the common actives on plumping gloss ingredient lists, which in the EU use the international nomenclature of cosmetic ingredients (INCI), and what each one does.

The Gucci gloss, sold at €41.40, combines menthyl lactate, methyl nicotinate and Capsicum frutescens extract and prints a warning about the tingling sensation (Cult Beauty). In the EU, a product that causes a sensation should say so on the pack, and a plumping claim must be substantiated under the common criteria for cosmetic claims (CIRS).

What do hyaluronic acid and peptides do instead?

Hydrating plumpers do not swell the lip. They change how the surface looks. A lip that has lost water shows fine vertical lines and a dull, slightly shrunken surface. A humectant draws water into the outer layer, the lines soften and the lip looks smoother and rounder in the light. The effect appears within minutes and fades as the product wears off.

The claims that go with these products come from brand panels. Laneige states that its Glaze Craze Tinted Lip Serum, US$22, with polypeptide, argan ceramides, polyglutamic acid and squalane, made lips look 39% plumper immediately in a self-assessment by 30 women (Laneige). A self-assessment measures what participants saw, not a change in tissue. Charlotte Tilbury's Collagen Lip Bath, €32.20, mixes both routes: marine collagen and sodium hyaluronate for hydration, mustard sprout extract for plumping and peppermint extract for a tingle (Cult Beauty).

Peptides are short chains of amino acids. In skincare they are used as signal molecules linked to collagen production. In a lip gloss the contact time is short and the dose is small, so the visible plumping in these products comes from the humectants and the shine, with the peptide as the story.

How much do lips plump, and for how long?

The change is small and short. Dr Kung's description, a mild and brief plumping due to transient swelling, is the real scale of it. The effect from an irritant plumper lasts a few hours at most and varies by product and person (Yahoo Health). A hydrating plumper fades with the film, which for a gloss is about an hour of talking and drinking.

No gloss adds lasting volume. The tingle is a sensation, not a measure of result, and a stronger sting does not mean more fullness. Lasting change in lip volume comes only from medical procedures, which are outside the scope of a cosmetic.

Who should skip plumping gloss?

Irritant plumpers are the wrong product for anyone whose lips are already inflamed. The American Academy of Dermatology tells people with chapped lips to stop using products that contain camphor, eucalyptus, menthol and cinnamon, citrus, mint or peppermint flavours, because these irritate cracked skin further. That list covers most tingling glosses.

• Cracked, peeling or sunburnt lips: use a plain balm until healed.
• Eczema or dermatitis around the mouth: skip irritant plumpers; a humectant gloss is usually fine.
• A history of cold sores: irritation and swelling can trigger an outbreak in some people.
• A known allergy to cinnamon, capsicum, mint or nickel-related flavourings: avoid the ingredient wherever it appears.
• Sensitive skin in general: choose the hyaluronic route and patch test first.

Dermatologist Debra Jaliman notes that plumping glosses are generally safe unless you are allergic to an ingredient, and lists hyaluronic acid, peptides, collagen, vitamin E and plant oils such as shea butter and castor oil as the safest daily choices (Yahoo Health). If a plumper causes swelling beyond the lip line, hives, blistering or a rash that does not settle within a day or two, stop using it and see a GP or a dermatologist. A persistent rash around the mouth from repeated use is an irritant dermatitis and needs the same care.

How do you use a plumping gloss safely?

You will need

• The plumping gloss, with its ingredient list read once
• A plain balm for the night before
• A clean patch of skin on the inner forearm for a patch test
• A clock

1. Read the list. Menthol, capsicum, cinnamon or methyl nicotinate means an irritant plumper. Sodium hyaluronate or polyglutamic acid with none of those means a hydrating one.
2. Patch test an irritant plumper on the inner forearm and wait 24 hours. Redness that persists means the product is not for you.
3. Apply balm the night before, so the lips are smooth. Never apply a plumper over flakes or cracks.
4. Apply one thin coat to clean, bare lips. Do not press or rub, which spreads the irritant to the skin around the mouth.
5. Wait. The tingle peaks within a few minutes and the swelling follows. Adding more does not add fullness.
6. Limit an irritant plumper to occasions. Frequent, daily use is what causes the rashes Dr Kung warns about.
7. Remove with a gentle cleanser in the evening and follow with balm.

“Applying irritants to your lips encourages blood to flow to the skin's surface, which creates a mild and brief plumping of the lips due to transient swelling.”

Elaine F. Kung, MD, Dermatologist and Clinical Assistant Professor at Weill Cornell Medical College, quoted by Yahoo Health