What not to mix with sunscreen?

Avoid mixing sunscreen with other products in your palm before applying. Be mindful about using highly acidic products like vitamin C serums or AHAs at the same time as sunscreen, as very low pH actives can potentially affect certain UV filters. The safest approach is to layer products in the correct order rather than blending them together.

The interaction between sunscreen and other skincare actives is an area of ongoing research. Some studies suggest that vitamin C (ascorbic acid) at a low pH can degrade certain chemical UV filters over time. The practical implication is to apply vitamin C serum first, allow it to absorb, then apply sunscreen on top as a separate layer. AHAs and BHAs also increase photosensitivity, which makes the sunscreen layer even more important on mornings you use these. Retinol is best used at night to avoid this concern altogether. Correct layering solves most compatibility issues without needing to eliminate any step.