Age spots (also called liver spots or solar lentigo) are collections of pigment caused by exposure to the sun. They also sometimes result from bruising that leaves blood pigments behind. They are most common in people over age 55. The spots commonly appear on the hands but can occur almost anywhere, especially sun-exposed areas such as the face, back, arms, feet, shoulders and face. These spots are common on the backs of the hand, face and legs. Those who tan extensively will also have them over the shoulders, back, chest and many other areas of skin. Lentigines are superficial collections of skin pigment called melanin which have accumulated within the top layer of skin called the epidermis. Ephelides are common in lighter type skin in individuals who sunburn easily. Lentigines usually appear later in life and can occur in all skin types. http://skin-care.health-cares.net/age-spots.php If you're a teen, chances are pretty good that you have some acne. Almost 8 in 10 teens have acne, along with many adults. Acne is a condition of the skin that shows up as different types of bumps. These bumps can be blackheads, whiteheads, pimples, or cysts. Teens get acne because of the hormonal changes that come with puberty. If your parents had acne as teens, it's more likely that you will, too. The good news is that, for most people, acne goes away almost completely by the time they are out of their teens. The type of acne that a lot of teens get is called acne vulgaris (the meaning of "vulgaris" isn't as bad as it sounds — it means "of the common type"). It usually shows up on the face, neck, shoulders, upper back, and chest. The hair follicles, or pores, in your skin contain sebaceous glands (also called oil glands). These glands make sebum, which is an oil that lubricates your hair and skin. Most of the time, the sebaceous glands make the right amount of sebum. As a teen's body begins to mature and develop, though, hormones stimulate the sebaceous glands to make more sebum, and the glands may become overactive. Pores become clogged if there is too much sebum and too many dead skin cells. Bacteria (especially one called Propionibacterium acnes) can then get trapped inside the pores and multiply, causing swelling and redness — the start of acne. If a pore gets clogged up and closes but bulges out from the skin, you're left with a whitehead. If a pore gets clogged up but stays open, the top surface can darken and you're left with a blackhead. Sometimes the wall of the pore opens, allowing sebum, bacteria, and dead skin cells to make their way under the skin — and you're left with a small, red bump called a pimple (sometimes pimples have a pus-filled top from the body's reaction to the bacterial infection). Clogged pores that open up very deep in the skin can cause nodules, which are infected lumps or cysts that are bigger than pimples and can be painful. There are a few myths out there about things that cause acne. Acne isn't caused by eating greasy foods like french fries or pizza, chomping on chocolate, or drinking sodas. Some people do find that they notice their breakouts get more severe when they eat too much of a certain food, though. If you're one of them, it's worth trying to cut back on that food to see what happens. Stress doesn't usually cause acne either (although it can make existing acne worse because stress increases sebum production). There are also myths about what helps make acne better. Acne isn't really helped by the sun. Although a tan can temporarily make acne look less severe, it won't help it go away permanently — and some people find that the oils their skin produces after being in the sun make their pimples worse. http://www.kidshealth.org/teen/your_body/skin_stuff/acne.html