You've heard the statistics. Smoking causes three million deaths per year worldwide.1-2It causes many forms of cancer and untold pain and suffering, not to mention billions of dollars in preventable health care costs. Common sense would say that smoking negatively affects almost every bodily condition, including acne. But evidence remains unclear whether this is true.3-9
To date, nine studies have examined the association between smoking and acne. Of these, three reported that smoking actually reduces acne, at least in some populations.4,7-8
A study published in the Journal of Investigative Dermatology in 2006 in which trained nurses interviewed 27,083 young men over a 20 year period came to a surprising conclusion: "Active smokers showed a significantly lower prevalence of severe acne than nonsmokers."4
In another study, published in 2007 in the Journal of the European Academy of Dermatology and Venereology, researchers reported that of the 594 participants studied, "In girls, smoking was significantly associated with lower prevalence of acne. No significant associations between acne and smoking variables were detected among boys."7
A third study, published in the journal Clinical and Experimental Dermatology in 1993 interviewed 165 patients with acne. “Amongst 96 males, 19.7% were smokers compared to an expected prevalence of 34.5% from national statistics. For 69 females, a prevalence of 12.1% was obtained compared to 32.7% expected. The findings of this study support the hypothesis that some component of cigarette smoke, possibly nicotine, has an anti-inflammatory action on acne.”8
However, four studies reached the opposite conclusion, that smoking is associated with increased acne.5,9-11
A study published in the British Journal of Dermatology in 2001 examined 896 men and women and showed that smokers tended to have a higher incidence of acne, and the more they smoked, the more severe their acne presented itself.5
Similar results were reported by a study published in 2004 in Clinical and Experimental Dermatology, which examined 1264 patients with acne from India and Hong Kong. “When data from both geographical locations were collectively analysed, we again found that significantly more male patients with acne than male controls were smokers. The difference was insignificant for females.”9
A more recent study of 1046 adult women performed in 2009 showed a "strong correlation" between smoking and non-inflammatory acne.11
The most recent study to find a correlation between smoking and acne came in 2012 and looked at 17,345 Chinese adolescents and adults. Data pointed toward a significant association with adolescent acne.10
Other studies have showed no statistical difference between smokers and non-smokers in regards to acne.3,6In short, evidence is conflicting and the medical research community needs quite a bit more data to come to a consensus.
Smoking Impairs Wound Healing and Worsens Skin Appearance
While smoking may or may not aggravate acne, it does harm the skin.12Among other things, smoking is linked to poor wound healing. Medically speaking, acne lesions are wounds, and thus it would make sense that smoking might cause our bodies to heal acne lesions more slowly. In order for acne lesions to heal, the skin needs to receive sufficient blood supply, and skin cells need to divide in order to make new cells to repair the wound. Smoking reduces these functions and considerably slows down the healing process.1-2
Smoking is also closely associated with wrinkles and premature skin aging. Quitting smoking, or not taking up smoking in the first place, is one of the best preventative measures against premature aging. Smoking also stains the teeth and can hasten hair loss.1-2Not surprisingly, in surveys of body esteem, smokers tend to rank lower than non-smokers.13
Smoking Increases Inflammation
Harmful effects of smoking are largely due to the fact that smoking results in the production of compounds called free radicals, which cause the body to produce inflammatory molecules called cytokines.14These molecules play a role in the early stages of acne formation. Studies have shown that cytokine levels are high in clogged pores and when healthy skin is exposed to high levels of cytokines, it starts to develop acne.15
What about e-cigarettes? A study published in 2016 in the journal Chest showed that tobacco and electronic cigarettes both increase the levels of inflammatory molecules (sNOX2-dp and 8-isoPGF2a) and decrease the levels of anti-inflammatory molecules (vitamin E and nitric oxide) in the blood. “After having smoked either a T-cigarette or an E-cigarette, significant changes in the levels of sNox2-dp, 8-isoPGF2α, Vitamin E and NO bioavailability (were found).”14
Smoking May Change Hormone Levels
One of the ways that smoking may influence acne is by changing hormone levels. Hormones, particularly higher than normal levels of testosterone in both men and women, and imbalances of the female hormones estrogen and progesterone in women, are known to worsen acne. Studies have shown that smoking reduces levels of estrogen in women and can impair the function of the ovaries, the organs that produce estrogen. Smoking can also cause menstrual cycles to become irregular.
The link between smoking and testosterone is not as clear, with studies reporting conflicting data. Testosterone is present in both males and females, and is intricately linked with acne. Higher testosterone levels usually mean more incidence and severity of acne. We only have research on testosterone levels in male smokers at this time. The research suggests that bioavailable testosterone, or the testosterone available to the body’s tissues, seems to remain unchanged in smokers. A review in the European Journal of Endocrinology concluded, “Significantly increased, decreased and unchanged levels of total testosterone in male smokers have been reported in various studies…No significant differences in the levels of bioavailable testosterone have been demonstrated between smokers and nonsmokers.”16
Nicotine, the Wild Card
As with many things in life, there are exceptions to the rule. For instance, evidence is showing that smoking may actually help protect against mouth sores and rosacea. The potential positive effects of smoking are most likely from nicotine, and not from smoking itself. Nicotine by itself is not necessarily harmful. In the case of acne, the constriction of blood vessels that nicotine produces may inhibit the production of more severe forms of acne in a lucky few people.17How and if this happens is still up to debate.