Sunflower seed oil is actually good for your skin barrier—it kept skin hydration up and caused no irritation over 4 weeks. Olive oil, on the other hand, actively damaged the skin barrier and caused redness, even in people without sensitive skin. The takeaway: not all natural oils are created equal.
19 adults tested oils on their forearms for 4-5 weeks in controlled studies. Researchers measured skin barrier integrity, hydration, pH, and redness before and after.
Funding not disclosed in abstract