Living an unhealthy lifestyle can age a woman's skin by over ten years, an in-depth international study has revealed.
The true damage caused by sun beds, smoking and a lack of fruit and moisturisation in accelerating the ageing process emerged following research on 585 women in the UK, China and Spain.
The study, published yesterday, showed the factors influencing their skin were the same even taking into account the backgrounds and skin type of the women involved.
It also emerged 'lifestyle choices' often account for as much as 33 per cent of how old a woman looks.
Dr Andrew Mayes, who led the study for Simple skincare, said: 'We already knew genetics accounted for about 50 per cent of how old people look, but we didn't know how much would be accounted for by their lifestyles.
'Even we were surprised by just how much it was; both in terms of the number of years and the percentage.'
The study which was carried out over the last eight years involved women aged 45 to 75 in the UK, 30 to 70 in Spain and 25 to 70 in China.
Study sites with controlled laboratory conditions were established in Bedford in the UK, Madrid in Spain and Shanghai in China.
Those who took part were asked a string of questions about their lifestyles including whether or not they liked to sun tan and if they were smokers or non-smokers.
Other questions included how often the women moisturised, whether they eat fruit and veg, whether they brush their teeth and if they have all their own teeth.
The research team also took digital images of the women which were then assessed for how old they looked to identify their perceived age and whether they looked younger or older than their actual age.
The research team, led by Dr Mayes, then compared the perceived ages of those with good versus bad lifestyles.
They concluded the difference was 10.4 years.
Dr Mayes added: 'The number of years' difference was most staggering - we had just seen some data out of a group of plastic surgeons in the US and Canada suggesting that a face and neck lift (together with eyelid and forehead modifications) could take an average of about 8.5 years off your facial age.
'Then we got our data through demonstrating a saving of over 10 years. It's fair to say at first we couldn't quite believe it.
'But the evidence was there in front of us - women with a healthy lifestyle looked much younger than those with an unhealthy lifestyle.
'Simply put; good skin health is about more than fancy creams and lotions - it's about how we live our lives and how we treat our bodies and the steps we need to take do not need to be extreme.
'They can be small and steady and the effects will be seen over time without the need for plastic surgery.'