Why We Formulate with Bio-Identical Lipids
Your skin barrier is a highly organized structure, often compared to a brick-and-mortar wall. The "bricks" are your skin cells (corneocytes), and the "mortar" holding them together is a precise mixture of lipids.
When your barrier is healthy, this mortar prevents water from escaping and irritants from entering. When it is damaged, you experience dryness, redness, and sensitivity.
The Golden Ratio
The mortar in a healthy human skin barrier is composed of three primary lipids in a very specific, naturally occurring ratio:
- 50% Ceramides
- 25% Cholesterol
- 10-15% Free Fatty Acids (predominantly Stearic Acid)
Researchers describe the best balance differently depending on age and skin condition, so there isn't one fixed ratio that suits everyone.
At Iduna, we choose lipids that resemble the ones your skin makes and match them to what each product is for. Not every product uses ceramides or cholesterol: AquaBio Botanical, for example, is built on plant oils, so check each product's ingredient list.
Why the Ratio Matters
Applying just ceramides, or just cholesterol, is often insufficient for true barrier repair. In fact, studies have shown that applying a single lipid to damaged skin can sometimes delay the repair process, as it further disrupts the natural balance.
Supplying these lipids together, rather than one at a time, is what the research on barrier repair points to.