The Correlations between Follicular Fluorescence and Casual Sebum Levels in Subjects with Normal Skin.

Performing objective measurements of skin oiliness requires a device that can directly measure the sebum level on the skin surface, while ultraviolet-induced red fluorescence (UVRF) can be used to indirectly assess the oiliness on the skin. There have been reports showing the association between these two methods in subjects with oily skin, acne-prone skin, but not in subjects with normal skin. We sought to study the association between UVRF and casual sebum level in terms of assessing the facial oiliness in individuals with normal skin. Thirty subjects with normal skin were recruited for measurements of both casual sebum level and UVRF (porphyrin count) on specified areas of the face (i.e., forehead, nose, and cheek). There were very strong positive correlations with statistical significance in the areas of the forehead, nose, and cheeks (r=0.88, <0.001; r=0.89, <0.001; and r=0.95, <0.001, respectively) when porphyrin counts in each area were compared to those of the whole face. Porphyrin counts were also positively correlated with the casual sebum level with statistical significance on the cheeks (r=0.43, =0.02), while the forehead and nose showed more modest correlations without statistical significance (r=0.35, =0.06 and r=0.36, =0.05, respectively). UVRF is correlated with casual sebum level. It might be useful for evaluating the facial oiliness of people with normal skin.