Looking after oily skin
It's not just teenagers who have oily skin, for many people of all ages it's a fact of life.
"Just as some people are tall and some people are short – some people have dry skin and some people have oily skin – it is part of the natural spectrum and is probably genetic in origin," says consultant dermatologist Dr John Ashworth.
So while genes can play a part, if your mum or dad had oily skin you are more likely to have it as well, hormones, especially in women, can also have an effect.
"Hormonal changes can also be responsible for oily skin as an adult, especially with the onset of your menstrual cycle, during pregnancy and the menopause," says Hermione Lawson from the British Skin Foundation.
For both sexes oily skin can by stimulated by a physical or emotional situation.
"It can be caused by stress, weather and even stimulation by aggressive scrubbing or washing," says Hermione.
Where does the oil come from?
Oil is produced by the sebaceous glands.
"Some people have overactive sebaceous glands that produce excess sebum, or oil, that contributes to the look of oily skin," says Matt Gass from the British Association of Dermatologists.
The glands are more plentiful in the face, neck, chest, head and back, so that's why those areas tend to be affected by oil production the most.
To get from the glands to your skin the oil flows into nearby follicular pores, and eventually works its way to the surface. When too much oil is produced skin no longer looks healthy but shiny and greasy.
Whatever's causing your oily skin there are steps you can take to control it, so you get more glow and less shine.
Keep it clean
It's tempting to use the strongest products on the market to wash away the oil but that's not the answer.
"Don't overly scrub your skin or use harsh, abrasive cleansers thinking that this will help. It is likely to just inflame your skin and could make it worse," says Matt.
Oil production is increased by irritation, so a stronger cleanser may make your skin produce more oil, which defeats the object.
So when it comes to cleansing go gently.
You may need a couple of different cleansers depending on the time of year. In colder months your skin will naturally be drier so use a very gentle cleanser. In the summer when your skin may be sweaty as well, you may prefer a more thorough, deeper cleaning product.
"You may find using a cleanser and toner that contains salicylic acid or benzoyl peroxide will help," says Hermione.
Oil free cosmetics
With oily skin use powder or mineral based cosmetics rather than those that are oil based and avoid crème blushers and eyeshadows, stick to powder-based.
"Choose oil-free, water-based cosmetics that are labelled as being 'non-comedogenic', which means they should not block the pores and cause spots," says Matt. "Remove make-up at night with mild soap or a gentle cleanser."
Avoid using everyday hand soap on your face as it's too harsh and may cause irritation and strip the skin of the oils it actually needs.