Ageing effect is worse among women
Smokers in their 20s are biologically two decades older than they should be, researchers have discovered.
Scientists analysed blood samples from tens of thousands of volunteers to assess how smoking can affect biological ageing.
They predicted the majority of smokers under the age of 30 to actually be aged between 31 and 40, or 41 to 50.
On the other hand, the ages of 62% of the non-smokers were calculated accurately, the researchers found.
The same trend was found for 31 to 40 year olds, in which the ages of almost half of the smokers were predicted to be 41 to 50.
Older smokers did not show such effects, possibly because those most affected had already died, according to the study reported in the Daily Mail.
The research, carried out by Baltimore-based artificial intelligence solutions company Insilico Medicine, looked at the blood profiles of 149,000 adults, of which 33% (49,000) reported being smokers.
The researchers combined an age-prediction model using a technique called deep learning and various biochemical markers among the participants.
These included levels of blood sugar, fasting glucose, iron stores and urea, a waste product excreted in urine.
The findings, published in Scientific Reports, showed that female smokers were worse off than males in terms of their biological age.
Study author Dr Polina Mamoshina said the study provides scientific evidence that smoking is likely to accelerate ageing.