To put it simply, pimples appear when the oil glands (pores) in the skin get blocked. 

Hormones make the oil glands produce more oil (sebum) and if a pore becomes blocked, the oil builds up and causes irritation. Bacteria multiply quickly in these blocked pores, which can make the redness, swelling and tenderness of pimples worse.

Your face, neck, chest, shoulders and upper back are most likely to be affected by acne because they have the highest number of oil glands. 

Acne usually starts at puberty when increased levels of sex hormones (known as androgens) create an increase in the size and oil production of glands.   Androgens are male hormones and are the same hormones that stimulate the growth of facial hair, muscle development and other distinctly male characteristics. 

You may have a higher chance of developing acne if other people in your family have had it too.


Acne is the most common skin disease

If you have acne, you’re not alone. It’s the most common of skin diseases – affecting 85% of Australians aged 15-24 years old. And it doesn’t matter whether you’re a guy or girl as both sexes get acne.

Teenage boys and young men have higher levels of androgens (male hormones like testosterone) than teenage girls so they are more likely to have acne, and unfortunately, are also more likely to have severe acne. 

Androgens are not the only hormones that play a role in acne. Many women and teenage girls notice their acne worsens just before their period. This is due to changes in female sex hormones (such as oestrogen), which can contribute to blockage and inflammation of pores. 

Women are more likely to suffer with ongoing acne. In some cases, this means acne can be hanging around even in your 30s and 40s. Women can also develop acne for the first time later in life and bear the burden of adult acne – a frustrating condition that’s becoming more common and appears to be linked to both hormones and stress.

Hormonal changes related to pregnancy or to stopping and starting oral contraceptives (the pill) can cause acne in some women. 

Once you reach your mid-20s, acne often clears up by itself, especially in men.  However, for some young people acne is a serious, ongoing problem that needs medical help for the physical and psychological issues acne can sometimes cause.

There are a number of lifestyle factors that can affect acne including stress, diet and exercise. Weight can also affect acne. In women, acne can be aggravated by pregnancy and conditions like polycystic ovarian syndrome.

Find out about treatments for acne