Association between processed meat intake and asthma symptoms in the French NutriNet-Santé cohort.

PURPOSE: Processed meat intake may adversely affect lung health, but data on asthma remains sparse. The magnitude of the processed meat-asthma association may also depend on other unhealthy behaviors. We investigated the association between processed meat intake and the asthma symptom score, and the combined role of unhealthy weight, smoking, low diet quality, and high processed meat intake on the asthma score. METHODS: In 2017, 35,380 participants to the NutriNet-Santé cohort answered a detailed respiratory web-questionnaire. Asthma was defined by the asthma symptom score (sum of 5 questions; continuous variable). Based on repeated 24-h dietary records collected on a dedicated website, processed meat consumption was classified as 0, < 2, 2-5, > 5 servings/week. We examined the combined role of body mass index (BMI) (< 25 vs. ≥ 25 kg/m2), smoking (never vs. ever), diet quality score (highest vs. lowest), and processed meat (≤ 5 vs. > 5 servings/week) on the asthma symptom score. RESULTS: Participants were aged 54 on average (women: 75%, smokers: 49%, BMI ≥ 25: 32%, ≥ 1 asthma symptoms: 27%). After adjustment for confounders, processed meat intake was positively and significantly associated with asthma symptom score: odds ratios (ORs) (95% CI) for > 5 vs. 0 servings/week were 1.15 (1.04-1.27) in women; 1.23 (1.01-1.50) in men. Compared to participants with 0 unhealthy behaviors, ORs for the asthma symptom score among participants with the 4 combined unhealthy behaviors were 2.18 (1.91-2.48) in women; 2.70 (2.10-3.45) in men. CONCLUSION: High processed meat consumption was associated with higher asthma symptoms, and combining overweight/obesity, smoking, low diet quality, with high processed meat intake was strongly associated with asthma symptoms.