Diffuse facial redness appears for several reasons: sun damage, rosacea, acne scarring, other types of scars, keratosis pilaris, sensitive skin, and genetics. The redness can be present all the time, or become more noticeable with certain trigger factors such as heat, wind, exercise, or wine consumption. An increased number of very superficial blood vessels, combined with sensitive skin or skin that flushes easily, leads to the increased red appearance of the skin.