The 11,613 study participants, aged 21-93 years and with an average age of 51, were tracked for almost 12 years by a team of researchers in Denmark.
Smokers accounted for 57% of female participants and 67% of male participants. Average alcohol consumption was 2.6 drinks per week for women and 11.4 for men.
The researchers studied four signs of aging that have previously been linked to a heightened risk of cardiovascular ill health and/or death: earlobe creases; a greyish opaque colored ring or arc around the peripheral cornea of both eyes (arcus corneae); yellow-orange plaques on the eyelids (xanthelasmata); and male pattern baldness (receding hairline or a bald patch on the top of the head).
The most common sign of aging among both sexes was arcus corneae, with a prevalence of 60% in men and 70% in women.
The study found that those who smoked and drank heavily had a consistently heightened risk of looking older than their true age, as well as developing arcus corneae, earlobe creases and xanthelasmata.
Smoking also in the spotlight
In detail, compared to weekly alcohol consumption of up to seven glasses, a total 28 glasses or more was associated with a 33% heightened risk of arcus coneae among female participants and 35% among men who drank 35 glasses or more per week.
Moderate drinking is defined as up to one glass of alcohol per day for women or men age 65 and over, and up to two glasses per day for adult men under 65.
Moreover, the study found that smoking a packet of 20 cigarettes per day for 15 to 30 years was associated with a 41% heightened risk among women and 12% among men, compared to non-smokers.
However, the occurrence of the visible signs of aging was no different among light-to-moderate drinkers than it was among non-drinkers, the research showed.
Finally, male pattern baldness was not consistently associated with heavy drinking or smoking. The researchers suggest that this may be because it is more strongly linked to genes and male hormone levels.