The vitamin your moisturiser is missing and what it does

There's a vitamin that strengthens your skin barrier, reduces inflammation, slows visible ageing and has documented benefits for eczema and psoriasis.

Most skincare doesn't include it. Not because it doesn't work, but because water-based creams can't carry it effectively.

Vitamin D is fat-soluble.

What vitamin D does to your skin

Research published in PMC (2024) found that vitamin D and its metabolites exert anti-ageing and protective effects on skin through anti-inflammatory action and by regulating the keratinocytes responsible for maintaining the skin's barrier.

In practical terms, vitamin D does three things your skin needs:

• Barrier repair. Vitamin D directly upregulates the enzymes responsible for lipid synthesis in the stratum corneum — the outermost skin layer that prevents moisture loss and blocks irritants. When the barrier is compromised, vitamin D supports the structural process that rebuilds it.
• Anti-inflammatory action. Vitamin D inhibits the production of inflammatory cytokines. For dry, reactive, or eczema-prone skin where chronic inflammation is the underlying problem, this matters. There is a documented link between vitamin D deficiency and higher rates of atopic dermatitis.
• Collagen protection. Vitamin D inhibits collagenase, the enzyme that breaks down collagen. Less collagenase activity means slower collagen degradation and less visible ageing over time.

Why most skincare can't deliver it

Fat-soluble vitamins require a fat matrix to be absorbed through the skin. Applied in a water-based cream, vitamin D sits on the surface. It can't cross into the lipid layers where it's needed.

In tallow, it travels in the same kind of lipid environment your skin barrier is built from.

Tallow contains it naturally

Grass-fed beef tallow naturally contains vitamin D alongside vitamins A, E and K. No synthetic addition required. The fat is both the carrier and the source.

Everyday Tallow Balm and SOS Relief Tallow Balm both carry vitamin D, whereas water-based skincare simply cannot.