INTRODUCTION

As the demographic shifts toward an older population and life expectancy continues to rise, the process of aging becomes unavoidable, leading to a heightened focus on its implications for all humans. The skin, being the body’s largest organ and constantly exposed to external harmful factors, exhibits the most apparent signs of aging. Skin aging is characterized as a gradual deterioration in the skin’s functional and regenerative abilities over time¹.

The following findings can be observed in skin aging: reduced skin thickness; fewer sweat glands and dermal blood vessels; a reduction in the density and functionality of melanocytes and Langerhans cells; degeneration of the elastic fibers; decreased collagen synthesis; and variations in bone and fat density². Two mechanisms contribute to skin aging. The first is intrinsic aging, which cannot be delayed or stopped and is determined by genetics, race, age, gender, and physiological processes. The second is extrinsic aging, influenced by various external factors, including sunlight, smoking, and dietary habits³. To delay aging, protection from these factors is crucial.

The effects of smoking on the skin have been previously investigated. A previous study found that smoking was associated with skin aging, and it increased perioral wrinkles in older women, but not in men⁴. Smoking increases the risk of delayed wound healing, allergic contact dermatitis, hidradenitis suppurativa, acne, androgenic alopecia, lupus erythematosus, polymorphous photodermatosis, and skin cancers (actinic keratosis, squamous cell carcinoma, basal cell carcinoma, melanoma, and anogenital cancer)⁵.

The demand for cosmetic procedures is growing due to the increasing variety of cosmetic surgeries, easier access, lower prices, and widespread use of social media. Interest is more common among women, although interest among men is also rising, and the age of initiation of cosmetic surgery is gradually decreasing^6,7. The desire to look more attractive in photos is the biggest driver of interest in cosmetic surgery. Reasons include the increasing use of social media, fascination with people portrayed in the media, feelings of inadequacy, and the desire for beautiful photos that lead to more interactions⁷.

The aim of this study was to compare skin properties, skin care product usage patterns, and the status of minimally invasive cosmetic procedures and self-evaluated skin quality based on smoking habits.

METHODS

Study design and participants

This is a cross-sectional study conducted in the Department of Dermatology outpatient clinic of Ordu University, Türkiye, between November 2023 and May 2024. The study consisted of 679 healthy individuals. The participants completed a self-administered questionnaire. The patients were recruited from the general dermatology clinic of Ordu University, with insignificant diseases, such as warts and calluses, and their healthy relatives and provided written informed consent before enrollment.

Participants eligible for inclusion in this cross-sectional study were adults aged between 18–65 years. All participants were required to provide informed consent and possess the ability to read, comprehend, and independently complete the questionnaire.

Exclusion criteria encompassed a history of dermatological conditions such as eczema, psoriasis, acne vulgaris, or vitiligo, as well as any systemic diseases known to affect skin quality, including but not limited to diabetes mellitus, thyroid disorders, autoimmune diseases, and chronic kidney or liver disorders. Participants with incomplete or inconsistent responses on the questionnaire were also excluded from the study. Prior to the study, ethical approval was obtained from the Ethics Committee of Ordu University (Approval number: 2023/289; Date: 10 November 2023).

A simple random sampling method was used to determine the study population. The first 13 questions of the questionnaire assessed demographic data and the frequency and duration of tobacco and alcohol use. Questions 14–36 focused on skin type, the use of skin care products, and cosmetic procedure applications. Question 37 asked participants to evaluate their own 12 body parts.

While preparing the study questionnaire, questions were formulated by examining previous studies and existing academic knowledge and current literature and previous studies. The questionnaire was analyzed by three dermatologists for content, measurement, and consistency. The questionnaire was revised according to their suggestions. The revised questionnaire was distributed to 10 people to analyze its comprehensibility and finalized according to their comments and suggestions. The finalized questionnaire was statistically analyzed after 30 participants completed it (Figure 1). The questionnaire was validated with reliability analysis (Cronbach’s alpha). The analysis shows excellent internal consistency among the 12 skin quality measurement items, with a Cronbach’s alpha of 0.859. This indicates high reliability of the scale as a measurement tool. The scale demonstrates strong internal consistency and appears to reliably measure whatever skin quality construct it was designed to assess.

Figure 1

Flow chart of the study

Demographic information (gender, age, education level, marital status, employment status, place of residence, and monthly income), smoking status, use of electronic cigarettes, status of waterpipe (shisha or hookah) smoking, alcohol usage, and skin type (dry, oily, normal, combination, or sensitive) were assessed. Additional questions about facial or body lesions (discoloration, freckles, redness/telangiectasia, acne, and scars), and frequency of makeup applications (always, frequently, on special occasions, and never). The participants were also asked about regular skin care product usage, use of dietary supplements for skin health, use of hand/face/body moisturizers, frequency of moisturizer use (every day, 1–2 times per week, as needed, or never), use of anti-aging products, regular skin care routines (masks, peels, or skin cleansing), and sun protection methods. The participants reported their sun protection practices, including protective clothing (hats, glasses, etc.), avoiding outdoor activities during peak hours (between 10:00 and 16:00), and sunscreen usage (only in summer, year-round, or never). The frequency of sunscreen reapplication (once daily, twice daily, or every 2–3 hours) and areas of application (face, hands, arms, neck, and décolleté) were also recorded. Other questions addressed cosmetic procedures such as neurotoxin injections, fillers, mesotherapy, and platelet-rich plasma injections, as well as the age of first application.

Smoking status and electronic cigarette use were categorized as active smokers, ex-smokers, and non-smokers. The duration of cigarette use and the quantity smoked were also assessed.

RESULTS

The validated questionnaire was distributed to 1000 individuals, of whom 721 returned the questionnaire; 42 completed questionnaires were excluded from the study because of missing or inappropriate results. The remaining 679 results were included in the statistical evaluation. The flowchart of the study is shown in Figure 1. The study population consisted of 286 males and 393 females. The age distribution of the study group was as follows: <20 (2.8%), 20–40 (63.2%), 41–60 (32.1%), and >60 years (1.9%); 4.6% were educated at primary school, and the rest were educated from at least high school; 60.4% were employed, and 80% were living in urban areas; and 32.9% of respondents had monthly earnings below the minimum wage. Smoking status was active, never, and ex-smoker in 42.4%, 45.8%, and 11.8%, respectively. E-cigarettes were actively used by 5.6%, never used by 87.2%, and 7.2% were ex-smokers; 9.3% were active hookah users, and 11.5% were ex-hookah users. The demographic characteristics of the participants are shown in Table 1.

The comparison of skin type, skin symptoms, and skin care product use between tobacco product users and non-users is presented in Table 2. The results of the chi-squared analysis showed that active smokers and individuals who had quit smoking were more likely to have a dry skin type, whereas individuals who had never smoked were more likely to have a normal skin type (p=0.012). According to post hoc Bonferroni analyses, the prevalence of dry skin was significantly lower in non-smokers compared to active smokers (p=0.042) and former smokers (p=0.018). The prevalence of normal skin was significantly higher in non-smokers than in active smokers and former smokers (p=0.008 and p=0.003, respectively). The rate of regular skin care was significantly lower in former smokers compared to never smokers and active smokers (p=0.025 and p=0.004, respectively). The frequency of body moisturizer use was significantly higher in non-smokers than in active smokers and former smokers (p=0.038 and p=0.012, respectively). Regarding the frequency of moisturizer use, daily use was more common among non-smokers, whereas never use was more prevalent among active smokers (p=0.022 and p=0.005, respectively).

The frequency of minimally invasive cosmetic procedures is shown in Table 3. According to the chi-squared analysis results, among the participants who had botulinum toxin injections, 59.5% were active smokers (p=0.006). Similarly, the majority of those who had undergone mesotherapy for skin pigmentations were active smokers (p=0.026). In post hoc Bonferroni analyses, the frequency of neurotoxin administration was significantly higher in active smokers compared to non-smokers (p=0.003) and former smokers (p=0.032). Additionally, the rate of hyperpigmentation mesotherapy was significantly higher in active smokers than in non-smokers (p=0.018).

Tables 4 and 5 present a comparison of perceived skin quality, wrinkles, and blemishes on 12 body regions between active smokers, ex-smokers, and never smokers. The chi-squared analysis results showed that compared to individuals who had never smoked, active smokers exhibited poorer skin quality, with more wrinkles, spots, and pigmentation on all 12 body areas (p<0.001). According to post hoc Bonferroni analyses, skin parameter values were significantly worse in active smokers compared to non-smokers across all body regions (p<0.001). Former smokers exhibited intermediate values, falling between those of non-smokers and active smokers (p<0.001).

The chi-squared analyses of e-cigarette and hookah use were as follows. Active electronic cigarette (e-cigarette) users had worse skin quality in the glabellar area, around the eyes, the mustache area, around the mouth, the neck, and the back region (p=0.026, p=0.034, p=0.011, p=0.021, p=0.039, and p=0.007, respectively). They also exhibited more pigmentation in the glabellar area and on the back (p=0.041 and p=0.07, respectively). Hookah users were found to have poorer back skin quality and increased pigmentation on the back (p=0.004 and p=0.009, respectively).

The total skin quality score was 25.47 ± 7.01, 27.35 ± 6.94, and 32.1 ± 3.71 for active smokers, ex-smokers, and never smokers, respectively. Total skin quality scores were also significantly worse in active smokers compared to never smokers (Figure 2A). A ROC analysis was performed to assess whether the total skin quality score could differentiate active smokers from never smokers, and to identify the threshold at which skin quality begins to decline (Figure 2B). The analysis yielded an area under the curve value of 0.792 (95% CI: 0.755–0.830). The cut-off value for the total skin quality score in active smokers was determined to be 30.5, with a sensitivity of 74.7% and a specificity of 72.0%.

Figure 2

Relationship between smoking status and total skin quality scores: A) Comparison of total skin quality scores by smoking status (one-way ANOVA followed by Bonferroni post hoc test); B) Estimation of the cut-off value at which active smokers begin to experience a deterioration in total skin quality score (ROC analysis)

The participants who used electronic cigarettes had worse total skin quality scores compared to those who had never used e-cigarettes (25.9 ± 6.28 vs 28.95 ± 6.54) (p=0.016). However, hookah use did not significantly affect total skin quality.

There was an inverse relationship between total skin quality and the number of cigarettes.

The regression model explained 34.7% of the total skin quality variance [R²=0.347, F(1, 676)=359.78, p<0.001]. This indicates that the duration of smoking has a moderate effect on skin quality. Each one-year increase in smoking duration is associated with a mean decrease in skin quality of 0.45 units. This effect is statistically significant (Beta= -0.589, p<0.001, 95% CI: -0.50 – -0.40), Constant term=31.43, p<0.001 (Figure 3A).

Figure 3

Correlation and regression analysis between smoking habits and total skin quality score: A) Analysis by smoking duration; B) Analysis by the number of cigarettes smoked per day

Linear regression analysis to examine the relationship between the number of cigarettes smoked per day and skin quality showed that cigarette consumption had a statistically significant negative effect on skin quality (B= -0.34, p<0.001). The model explained approximately 19% of the variance in skin quality (R²=0.189, Figure 3B).

The logistic regression analysis examined the association between smoking status and skin quality, including wrinkles and skin spots. The final model identified seven significant predictors, with Nagelkerke R²=0.31, indicating a moderate effect size. The model correctly classified 72.16% of cases, with higher accuracy for non-smokers (79.28%) than active smokers (62.5%).

Participants with good forehead skin quality were less likely to be smokers (B= -0.70, SE=0.22, p=0.001). The odds of being a smoker were 2.02 times lower (OR=2.02; 95% CI: 1.31–3.12) for those with good skin quality compared to those with poor quality. The presence of forehead skin spots was associated with a reduced likelihood of smoking (B= -0.64, SE=0.27, p=0.016, OR=1.90; 95% CI: 1.12–3.20). Participants with skin spots in the eyebrow area were 3.17 times more likely to be smokers (B=1.15, SE=0.36, p=0.001, OR=3.17; 95% CI: 1.56–6.47). Good skin quality around the eyes was linked to a lower likelihood of smoking (B= -0.84, SE=0.21, p<0.001, OR=2.33; 95% CI: 1.54–3.51). Better cheek skin quality was associated with a marginally reduced smoking likelihood (B= -0.41, SE=0.21, p=0.046, OR=1.51, 95% CI: 1.01–2.25). Good neck skin quality significantly predicted lower odds of smoking (B= -0.89, SE=0.26, p=0.001, OR=2.43; 95% CI: 1.45–4.09). The presence of skin spots (present) on the shoulders was strongly associated with higher odds of smoking (B=1.13, SE=0.24, p<0.001, OR=3.10; 95% CI: 1.94–4.93). The constant (intercept) was significant (B=1.35; SE=0.27, p<0.001), indicating baseline smoking odds when all predictors are zero.

Structural equation modelling (SEM) was used to examine the effect of smoking status (yes vs no), age groups (reference: <20, vs 20–40, 41–60 and >60 years) and gender (female vs male) on skin score. According to the results of the analysis, it was carried out to examine the effects of age groups, smoking status and gender on total skin quality. The model was estimated by maximum likelihood (ML) method and tested on a sample of 679 participants. The model fit indices showed an excellent fit (CFI=1.000, TLI=1.000, RMSEA=0.000, SRMR=0.000). The model explained 29.5% of the variance in skin quality (R²=0.295).

The findings regarding age groups showed that the age group of 41–60 years (compared to the <20 years reference group) led to a significant decrease in skin quality (β= -0.255, p=0.007). In the ≥60 years age group, this effect was even more pronounced (β= -0.192, p<0.001). Smoking had the strongest negative effect on skin quality (β= -0.449, p<0.001). In terms of gender, women reported lower skin quality compared to men (β= -0.136, p<0.001).

DISCUSSION

Skin aging is characterized by dryness, decreased epidermal and dermal thickness, wrinkle formation, cutaneous lesions, irregular pigmentations, age spots, sagging, hair greying, and inappropriate wound healing^12-15. As the most visible organ of the body, aging-related changes in the skin have a significant impact on individuals’ social lives and well-being³.

In a recent study, the authors investigated the skin aging characteristics of those perceived as elderly and found that skin tone and pigmentation were the most significant factors influencing perceived age in younger individuals, while wrinkles and sagging were more critical in older individuals. In addition, the cheeks, eyes, and forehead were strongly associated with perceived age¹⁶. Another study revealed that older age, urban living, tobacco smoke exposure, dry skin type, increased sun exposure, and working in toxic environments increased the odds of skin aging¹⁷. In our study, smoking, a primary cause of aging, was associated with worse perceived skin quality, more wrinkles, and blemishes. Active smokers frequently had a dry skin type. Furthermore, despite ultraviolet (UV) exposure being another important factor in aging, our study showed that effective sun protection practices were uncommon. Interestingly, even active smokers who consistently protected themselves from UV light exhibited poor skin quality, indicating that UV protection cannot mitigate the detrimental effects of smoking.

A meta-analysis examining factors influencing skin aging revealed conflicting findings regarding the impact of smoking on facial wrinkles and lentigines. However, all four studies included in the analysis found a dose-dependent correlation between smoking and wrinkles¹⁸. In our study, perceived skin quality decreased with increasing duration and quantity of smoking. It has been reported that smoking increases the activity of the matrix metalloproteinases-1 and -3, reducing collagen production, and it also increases the elastic fibers in the reticular dermis^4,5,19. Chen et al.²⁰ examined the effects of smoking on skin lipids, reporting that smoking disrupted lipid homeostasis, leaving the skin more vulnerable to aging and disorders. Our study corroborated these findings, as active smokers reported worse skin quality, more wrinkles, and increased skin pigmentation in all areas compared to never smokers.

The prevalence of e-cigarette use is rising, particularly among children and young adults. E-cigarette use can lead to nicotine dependence and associated adverse effects on the brain and lungs while also increasing susceptibility to tobacco and other substances^21,22. In our study, the rate of active e-cigarette users was 5.6%, and quitters comprised 7.2% of participants. E-cigarette users had worse skin quality between the eyebrows and around the eyes and mouth, and on the neck and back. Total skin quality was significantly lower among active e-cigarette users than never users. Since e-cigarette sales are prohibited in our nation, our survey found a low rate of e-cigarette use. Furthermore, some of the skin changes brought on by e-cigarettes may be related to smoking because some of the patients who use them are either current smokers or have stopped. These factors suggest that a bigger sample size be used to examine the effects of e-cigarette use on skin health.

Waterpipes contain nicotine, carbon monoxide, polycyclic hydrocarbons, and other toxicants, potentially rendering them more harmful than cigarette smoke. A study of adolescents aged 12–16 years across 72 countries, found a hookah use prevalence of 6.8%, with the highest rates in European Union and Eastern Mediterranean countries²³. In our study, the rate of active hookah users was 9.3%, with 11.5% classified as quitters. Hookah users exhibited poorer back skin quality and a higher rate of pigmentation in this area. However, it is important to note that some of the skin changes found in hookah users may be related to smoking, since participants who use hookah are likely to be active smokers and quit smoking, as well as passively exposed to cigarettes because they are in a smoking environment.

External factors influencing aging rarely act independently but often combine their effects¹⁹. A recent study investigating the combined effect of UV light and smoking on skin aging found that smoking and UVA1 exposure synergistically contributed to premature extrinsic aging²⁰. In our study, 71% of the participants reported using some form of sun protection, with 46.4% using sunscreen, 33.4% using sunscreen year-round, and only 5.3% reapplying sunscreen every 2–3 hours. Our data underscore the inadequacy of current sun protection methods.

The demand for cosmetic procedures is increasing. A recent study using qualitative semi-structured interviews identified motivations for minimally invasive dermatologic cosmetic procedures and reported that, in addition to enhanced cosmetic appearance, patients sought to improve mental, emotional, and physical well-being, as well as social, work, and/or school performance²⁴. According to the American Society for Dermatologic Surgery, the rate of cosmetic treatments doubled from 2013 to 2017, with wrinkle-relaxing procedures increasing by 60% from 2012 to 2019²⁵. In our study, neurotoxin injections were the most preferred cosmetic procedures, particularly among active smokers. In addition, mesotherapy for hyperpigmentation was more common in this group. Given the widespread desire to maintain a youthful appearance and prevent aging, leveraging the information that smokers are more likely to undergo cosmetic procedures, particularly neurotoxin applications, in smoking cessation campaigns could be an effective strategy to encourage individuals, especially young people, to quit smoking.

Several dermatological features significantly predicted smoking status. Notably, skin spots in the eyebrow and shoulder areas were associated with higher smoking odds, while good skin quality in the forehead, eye area, cheeks, and neck, was linked to reduced smoking likelihood. These findings suggest that visible skin characteristics may serve as markers for smoking behavior.

CONCLUSIONS

This study examined the effects of smoking and other tobacco products on skin quality, skin care routines, and approaches to minimally invasive cosmetic procedures. Active smokers exhibited poorer perceived skin quality and a higher frequency of wrinkles and blemishes in all body areas evaluated. Adverse effects of e-cigarettes and hookah on the skin were also observed. Smokers were more likely to have a dry skin type and sought neurotoxin treatments and mesotherapy more frequently. We consider that highlighting the negative effects of smoking on the skin, alongside its well-known role in triggering numerous diseases, including many organ cancers, could be beneficial in smoking cessation efforts.