Ingridient Glossary

A reference for the actives you will find across the eMaison catalogue. Not exhaustive. Not academic. Just the things worth knowing about the ingredients we chose and why we chose them.

Vitamin A — Retinol

The most studied active in skincare. Vitamin A accelerates cell turnover, improves skin texture, addresses pigmentation, and supports collagen production. It takes time — six to twelve weeks before meaningful change — and it requires introduction carefully, starting two nights a week and building from there. The French pharmacie version, A313, delivers the same active as prescription retinoids at a fraction of the price. It works. It has worked for decades. It simply requires patience.

Niacinamide — Vitamin B3

One of the most versatile actives available without a prescription. At 4–5%, niacinamide strengthens the skin barrier, reduces the appearance of pores, improves uneven tone, and calms reactive skin. It is well tolerated by almost all skin types, including sensitive skin. It works particularly well alongside hyaluronic acid and retinol. SVR's B3 Hydraliane Serum uses it at the working concentration.

Hyaluronic Acid

A molecule that holds water. At its most effective in multiple molecular weights — larger molecules sit on the surface and prevent moisture loss, smaller ones penetrate deeper and hold water within the skin. After forty, the skin produces less of its own hyaluronic acid. The reduction is gradual and shows as dryness, fine lines, and a loss of plumpness that no amount of drinking water addresses. Topical hyaluronic acid does not replace what is lost internally, but it manages the surface effectively when used correctly — applied to damp skin, sealed with a moisturiser on top.

Vitamin C — Ascorbic Acid

An antioxidant that neutralises the free radicals responsible for accelerating visible skin ageing and worsening pigmentation. Most effective in the morning, before SPF. Vitamin C makes SPF more effective — the two work together. It is also the active most frequently destabilised by poor formulation. SVR's Ampoule C uses a stabilised form that does not oxidise in the bottle.

Ceramides

The lipids that hold the skin barrier together. Oestrogen decline — which begins in perimenopause — directly reduces ceramide production. When ceramide levels fall, the barrier becomes permeable. Water escapes. Irritants enter. Everything becomes more reactive. Products that replenish ceramides address the root cause of most of what presents as sensitive or dry skin after forty. We look for them in moisturisers and barrier repair formulations.

Thermal Spring Water

Not a marketing ingredient. Avène's thermal spring water has a specific mineral composition — high silica, low mineral content — that has been studied for its effect on reactive and compromised skin. It is anti-irritant, not just soothing. The difference matters. Avène's Cicalfate and their SPF range are built around it.

SPF — Sun Protection Factor

The single most evidence-backed intervention available in skincare. Daily SPF50 reduces cumulative UV damage, prevents pigmentation from worsening, and protects the collagen that remains. Most people apply half the amount required for the stated protection. The number on the bottle assumes 2mg per square centimetre of skin — more than most people use. Apply generously. Reapply if you are outside for more than two hours. SPF applied once in the morning and not reapplied offers approximately two hours of meaningful protection.

Zinc Oxide and Titanium Dioxide

Mineral UV filters. They sit on the surface of the skin and reflect UV radiation rather than absorbing it. Better tolerated by reactive and sensitive skin than chemical filters. More likely to leave a white cast, though modern formulations have largely addressed this. Avène's Sunsimed uses a hybrid approach — mineral filters with minimal cast — formulated specifically for skin prone to pigmentation.

A word on fragrance

Fragrance is the most common cause of contact dermatitis in skincare. It serves no functional purpose in a skincare formulation — it is there for the experience of using the product, not for what it does to skin. Reactive skin and fragrance have a straightforward relationship. Where the formulation allows it, we choose fragrance-free. Where it does not, we tell you clearly in the product description.