Can foundation interfere with sunscreen ingredients?
Your welcome! For a “physical” sunscreen that has actives that are zinc or titanium, the answer is no. For the chemical sunscreens that rely on binding to skin cells to work, the answer is probably – but I’ve never seen any research done on this. For chemical sunscreens it may make sense to put them on first or only over an antioxidant serum or gel.
I absolutely disagree with the last statement. Zinc oxide is the only sunscreen ingredient that blocks both UVB well and the full spectrum of UVA. If you’re using a high percentage zinc sunscreen (8-20%) you don’t need a chemical sunscreen. Not sure who told you that, but hopefully it wasn’t a dermatologist. Link to sunscreens and more info on sunscreens.
Hope this helps, Dr. I