Smoking and Psoriasis: Is There a Link?

A landmark 2026 systematic review and meta-analysis published in Frontiers in Public Health analyzed 30 observational studies involving over 25 million participants. The findings were definitive [citation:1][citation:9].

• 📈 Current smokers: 67% increased risk of developing psoriasis compared to never smokers (summary relative estimate = 1.67, 95% CI: 1.46–1.90) [citation:1][citation:9].
• 📉 Former smokers: 38% increased risk compared to never smokers (summary relative estimate = 1.38, 95% CI: 1.18–1.62) — demonstrating that quitting reduces risk but does not eliminate it entirely [citation:1][citation:9].
• ⚠️ Dose-response relationship: The more you smoke, the higher your risk. An increase in the number of pack-years of smoking increased the risk of developing psoriasis [citation:1].
• 🔬 Comparison with alcohol: The study found that smoking shows a stronger and more consistent association with psoriasis risk than alcohol consumption, which showed a smaller and less consistent effect [citation:1][citation:9].

Researchers have identified several mechanisms by which cigarette smoke contributes to the development and exacerbation of psoriasis. A 2011 review in the British Journal of Dermatology outlined the key pathways [citation:6].

🔥 Oxidative Stress

Cigarette smoke contains thousands of chemicals that generate reactive oxygen species (ROS) — free radicals that damage cells. Smoking initiates the formation of free radicals that stimulate cell signalling pathways active in psoriasis, including mitogen-activated protein kinase (MAPK), nuclear factor-κB (NF-κB) and Janus kinase/signal transducers and activators of transcription (JAK-STAT) [citation:6]. Smoking damages the skin by increasing the formation of reactive oxygen species and decreasing the gene expression of antioxidants [citation:6].

🩸 Immune System Activation

Nicotine stimulates innate immune cells integral to the pathogenesis of psoriasis, including dendritic cells, macrophages, and keratinocytes. These cells release cytokines that activate T lymphocytes and perpetuate a cycle of chronic inflammation [citation:6]. A 2024 Stanford-indexed study noted that “psoriasis has a clear and strong connection with smoking in both its pathogenesis and clinical course” [citation:10].

🧬 Genetic Susceptibility

Smoking enhances the expression of genes known to confer an increased risk of psoriasis, including HLA-Cw6, HLA-DQA1*0201 and CYP1A1 [citation:6]. This may explain why some individuals are more susceptible to smoking-induced psoriasis than others.

🔄 The Inflammation Cycle

As illustrated in Figure 5 of a 2024 NIH publication, smoking behaviors may trigger psoriasis by activating inflammatory, oxidative, and genetic mechanisms mediated by free radicals and nicotine [citation:2]. The diagram shows how free radicals and nicotine contribute to the inflammatory cascade that drives psoriatic lesions.

Smoking doesn’t just increase the risk of developing psoriasis — it also makes existing psoriasis worse and complicates treatment [citation:10].

• 😔 Increased severity: Smoking can cause a serious worsening of both the disease itself and systemic complications such as cardiovascular events, psoriatic arthritis (PsA), cancer, and depression [citation:10].
• 💊 Reduced treatment response (biologics): A 2026 prospective study of 192 patients with psoriasis undergoing biologic treatment found that non-smokers had significantly higher PASI 75 response rates at weeks 4, 8, 12, 24, and 48. The adjusted odds ratios ranged from 2.57 to 2.75, meaning non-smokers were approximately 2.5x more likely to achieve good treatment response [citation:4].
• 📉 Dose-dependent effect: Both tobacco smoking duration and daily cigarette consumption were negatively correlated with the reduction in PASI score at weeks 4 to 48 after treatment (P < .05) [citation:4].
• 🩺 Reduced drug survival: An Australasian study found that on univariable analysis, smokers were 34% more likely to discontinue biologic treatment compared to non-smokers and were 27% less likely to attain PASI90 and 33% less likely to attain PASI100 [citation:8].

Psoriatic arthritis is a form of inflammatory arthritis that affects up to 30% of people with psoriasis. The relationship between smoking and PsA is complex.

• ⚠️ Smoking increases risk of developing PsA: The 2026 meta-analysis specifically examined subtype-specific outcomes including PsA and found that smoking is associated with an increased risk of developing psoriatic arthritis [citation:1].
• 🦿 Progression of joint damage: However, a 2025 study from the University of Toronto investigating 1,736 patients with PsA found that cigarette smoking did not appear to be significantly associated with the progression of joint damage in PsA (estimate -0.18, 95% CI -0.94 to 0.58 for current smokers) [citation:7].
• 📋 The bottom line: Smoking increases your risk of developing PsA, but once you have PsA, smoking may not accelerate joint damage progression. However, given the many other health risks of smoking, cessation remains strongly recommended.

The 2026 meta-analysis confirmed a positive dose-response relationship between smoking and psoriasis risk [citation:1][citation:9]. This means:

• ✅ The more cigarettes you smoke per day, the higher your risk
• ✅ The longer you smoke, the higher your risk
• ✅ Higher cumulative pack-years = higher risk
• ✅ Light smoking (fewer than 10 cigarettes/day) still increases risk, just not as much as heavy smoking

Non-smokers are not safe from smoking-related health effects — and psoriasis is no exception. The 2026 meta-analysis included data on passive smoking exposure, though the effect size is smaller than active smoking [citation:1].

• 👨‍👩‍👧 Children in smoking households are exposed to the same oxidative stress and immune-activating chemicals as active smokers
• 🏢 Occupational exposure in smoky workplaces may pose cumulative risk
• 🩺 Genetic susceptibility matters: Individuals with a family history of psoriasis may be more vulnerable to passive smoking effects

The evidence is clear: quitting smoking reduces your risk of developing psoriasis and improves outcomes if you already have it [citation:1][citation:5].

• 📉 Risk decreases after quitting: Former smokers have a 38% increased risk (down from 67% for current smokers) [citation:1][citation:9].
• ⏳ The longer you stay quit, the lower your risk: Smoking cessation was associated with a decreased risk of developing psoriasis, and the risk-reducing effect was more pronounced in those maintaining a smoke-free status [citation:5].
• 💊 Better treatment outcomes: Non-smokers with psoriasis have significantly higher response rates to biologic treatments [citation:4][citation:8].
• 🩺 Improved overall health: Quitting smoking reduces your risk of cardiovascular disease — a particularly important benefit since psoriasis itself increases cardiovascular risk.

All tobacco smoke triggers psoriasis — regardless of brand or source. Native cigarettes (Playfare, Canadian, DuMont, Nexus, Rolled Gold) contain the same nicotine, oxidative stressors, and immune-activating chemicals as commercial brands [citation:6].

• 💰 Cost savings: Native cigarettes cost $29-50 per carton — compared to $140-180 for commercial brands — a savings of 70-80%.
• 🚫 Not “healthier” for psoriasis: Native cigarettes cause the same oxidative stress, immune activation, and genetic effects as any other cigarette.
• 📦 Online delivery: Cigstore.ca ships to every province and territory with $29 flat shipping (free over $290).
• 🩺 Medical note: If you have psoriasis or are at risk, no form of smoking is safe — regardless of brand or price. Quitting is the only effective intervention.