Acne consists of spots and painful bumps on the skin. It's most noticeable on the face, but can also appear on the back, shoulders and buttocks. Severe acne can cause scarring.

What causes acne?

The causes of acne continue to be investigated by scientists, but even after decades of research there are no definite answers. It appears that a person's genes have the strongest influence on whether they get acne or not. This could be due to the way skin reacts to hormonal changes.

The skin contains sebaceous (oil) glands that naturally release sebum, an oily substance that helps protect it. During puberty, changes in levels of the hormone testosterone can cause changes in the sebum produced. This happens in both boys and girls.

The sebum can block hair follicles. When dead skin cells mix with the blockage, it can lead to the formation of spots. Bacteria in the skin multiply, which can cause pain and swelling (inflammation) beneath the blockages.

If you have acne, it can be made worse by:

• stress
• a poor diet
• being overweight
• not exercising enough
• being pregnant
• having polycystic ovarian syndrome.

There are different kinds of spots:

• blackheads are small, blocked pores
• whiteheads are small, hard bumps with a white centre
• pustules are spots with a lot of pus visible
• nodules are hard, painful lumps under the skin.

Inflammatory acne is when the skin is also red and swollen. This needs to be treated early to prevent scarring, and should be discussed with your doctor.

Try not to pick or squeeze spots as this can cause inflammation and lead to scarring. Spots will eventually go away on their own, but they might leave redness in the skin for some weeks or months afterwards.

If you have acne, wash your skin gently with a mild cleanser and use an oil-free moisturiser. Scrubbing or exfoliating can irritate the skin, making it look and feel sore.

Myths about acne

Several myths about what causes acne are described below.

Food

Research shows that eating low GI foods and cutting down on processed foods can help acne. But remember changing what you eat can only do so much. Medical treatments are still the main way to improve severe acne.

If you notice your acne is worse after you eat certain foods, cut these out for a while and see what happens.

Bad hygiene

Some people believe that acne is caused by bad personal hygiene, but this is not true. If you are going to get acne, you will get it no matter how much you clean your skin. Too much cleaning can make the condition worse by removing the protective oils in your skin.

Make-up

There is also a myth that wearing make-up can cause spots, but there is no evidence that this is the case. The less you touch your skin, the fewer bacteria will be spread to your skin. If you wear make-up, wash your hands before putting your make-up on and always remove it before going to bed.

If acne is severe, your doctor can refer you to a dermatologist who may prescribe medication.