There's more to the bacterium Cutibacterium acnes than meets the eye. Youngoldman/iStock via Getty Images PlusThe skin is the largest organ of the body, and it plays a crucial role as the first line of defense against pathogens and insults from the external environment. It provides important functions like temperature regulation and moisture retention. And despite the misconception that lipids harm your skin by causing oiliness and acne, they actually play a vital role in maintaining the skin