Acne is a common skin disease that is characterized by a variety of lesions: comedones (whiteheads and blackheads) papules (raised red areas), and pustules (raised skin eruptions filled with pus). Acne is most often found on the forehead, nose and cheeks, but body acne is also possible, and the legs, back and shoulders can be affected. Acne generally starts during adolescence and fades considerably during the 20s or 30s, but occasionally, someone can pass through adolescence unscathed and develop acne in his or her 30s or 40s.

The exact cause of acne vulgaris (the word acne comes for the Greek word for peak, and vulgaris means common) is not known, but an increase in hormonal activity, e.g., during puberty or menstruation, common skin bacteria, stress, and sebaceous glands (small glands under the skin) that are producing too much sebum (a thick secretion of fat and dead skin) may all contribute. There is likely no single cause for acne, but many factors, and there are many other explanations for why it occurs.

But although the exact cause of acne is not known, the process of the disease has been clearly outlined. The sebaceous glands are attached to hair follicles that start below the surface of the skin, and sebum normally passes to the surface of the skin through the hair follicles. However, in acne, there is an overproduction of sebum, and the skin cells that line the follicle and normally move to the surface with sebum proliferate. The combination of excess sebum and dead skin cells blocks the hair follicle, sebum builds up, and a whitehead or a blackhead is produced (Many people think blackheads are dirt in the pores; that's not true. The black color comes from a chemical change in the sebum/dead skin compound and from the presence of pigment cells). If the process continues, bacteria that are normally present in the skin (Propionibaterium acnes) find this environment very conducive to growth. The result? Infection, inflammation and the pus-filled lesions that most people associate with acne.

Acne can't be cured, but it can be managed, and this can be a challenge, especially if you have body acne with widespread lesions. Traditionally, people have been instructed to avoid certain foods such as french fries, potato chips, chocolate and others, but there is no definite evidence that these foods cause acne or make a pre-existing condition worse. The most basic and the simplest steps in treating acne are to keep the skin clean and oil-free (a real challenge for people with body acne). That sounds simple, but there are literally hundreds of acne products on the market - most of which promise more than they deliver - so it's hard to know which one to choose The quick answer is that there are no 'miracle' treatments and everything you need you can find at the local pharmacy. Use a mild, water-based skin cleanser that will not clog pores and use an exfoliant. Exfoliation removes the surface layer of dead skin cells and helps keep the pores open and draining.

The second step to treating body acne is topical treatments. There are a variety of these and you may have to experiment - at times with help from your doctor - to find one that works. Benzoyl peroxide is an antibacterial that can be purchased over the counter, and topical antibiotics such as erythromycin, clindamycin, and tetracycline can be used. These are especially useful for people with body acne as they can be applied directly to the areas with lesions.

If topical treatments are ineffective, you doctor may prescribe oral antibiotics (e.g., erythromycin, tetracycline) or for women, oral contraceptives; oral medications are also especially useful for people with body acne as a) topical treatments can be awkward or inconvenient to apply in hard to reach places, and b) oral medication is delivered directly to the affected areas below the surface of the skin. Oral retinoids such as isotretinoin reduce sebaceous gland secretions and can also be effective and light therapy has been used with some success; again, these treatments would be very convenient for people with body acne. Finally, one of the most important ways to treat acne is to use patience. It may take months for some of these therapies to make a difference and if you have a bad case of body acne, it can be difficult to wait.