Whether caused by sun damage, skin inflammation or aging, the origins of dark spots and uneven complexion lie deep within the skin. "Melanin is what gives skin its color and in excess can result in the appearance of dark spots and discoloration," explains Dr. Ranella Hirsch, board-certified dermatologist. "This can be the result of UV exposure or subsequent to inflammatory skin conditions such as acne. Dark spots affect many skin types and can be quite upsetting to those affected." In the following question and answer session, Hirsch explains the facts about uneven pigmentation and dark spots. Question: What is the most common cause of brown spots? Hirsch: Exposure to the sun's harmful UV rays is the number one cause of brown spots. Question: Are there certain areas of the body where brown spots are more common? Hirsch: The areas with the greatest sun exposure, like the face, hands and décolleté are the most prone to sun spots. Question: I've heard that acne can leave behind brown spots, too. Is this true? Hirsch: In patients with darker complexions, breakouts can be followed by sustained dark spots, which are clinically referred to as post-inflammatory hyperpigmentation (PIH). Question: Are certain ethnicities more prone to uneven pigmentation? Hirsch: People with darker skin naturally have more melanin at baseline, making them more likely to pigment as a response to skin irritation. Question: Are brown spots permanent? Hirsch: Dark spots caused by UV exposure will typically not go away without some sort of treatment. Question: What is the top preventative measure I can take to prevent and/or lessen the appearance of brown spots? Hirsch: Wear sunscreen everyday (yes, even in the winter). Also, be sure to reapply sunscreen often when exposed to the sun for extended periods of time. Sunscreen defends your skin against brown spots in two ways: It prevents new spots from forming. It stops pre-existing spots from darkening. Want to read more? Subscribe to one of our monthly plans to continue reading this article.