What Affects the Skin’s Absorption of Skincare Ingredients?

The skin can absorb certain external substances — but thanks to its natural barrier, it doesn't allow just anything to pass through. This protective function is essential to keeping harmful substances out. Unfortunately, some brands go to extremes, using harsh methods or formulations that damage the skin barrier just to increase absorption. Even some aesthetic treatments rely on micro-injuries to force active ingredients deeper into the skin.

So, what actually affects how well your skin absorbs skincare products?

1. Oil-Solubility vs. Water-Solubility

The outermost layer of the skin — the stratum corneum — is like a brick wall, with corneocytes as bricks and lipids as mortar. Based on the principle of "like dissolves like," oil-soluble ingredients are more readily absorbed because they can blend with the skin’s natural lipids and penetrate more deeply.

2. Thickness of the Stratum Corneum

The thicker the stratum corneum, the harder it is for skincare ingredients to penetrate. Thinner areas of skin — like the delicate area around the eyes — absorb products more easily, but also require gentler, milder formulas to avoid irritation. In contrast, thicker or calloused skin may need extra care to boost absorption.

3. Hydration Level of the Skin

When the skin is well-hydrated, the gaps between cells in the stratum corneum expand, allowing more ingredients to seep in. This is why using a toner, hydrating mist, or sheet mask before applying serums and creams can significantly enhance their effectiveness.

⚠️ However, over-hydration can do more harm than good — it may break down the skin barrier, causing sensitivity, dryness, and redness.

4. Molecular Size & Concentration of Ingredients

Smaller molecules penetrate the skin more easily than larger ones. Also, the actual concentration of active ingredients plays a crucial role — higher-quality products with meaningful levels of real actives (like VG’s essential oil-rich creams and serums) are far more effective than those that use trace amounts just to pad an ingredient list.

When you open a product and are met with a genuine botanical essential oil aroma, that’s often a sign of authentic, concentrated plant-based actives — not just marketing fluff.