Fruit, vegetable and dietary antioxidant intake in school age, respiratory health up to young adulthood

Background Dietary antioxidants may protect the lung against oxidative damage and prevent chronic respiratory disease. We aimed to investigate fruit, vegetable and antioxidant intake (measured as total antioxidant capacity, TAC) at age 8 years in relation to asthma and lung function up to 24 years. Methods In this study of 2506 participants from a Swedish birth cohort, diet was assessed using food frequency questionnaires. Information on asthma was collected by questionnaires, and lung function was measured by spirometry at ages 8, 16 and 24 years. Generalized estimating equations and mixed effect models were used to assess overall, age‐ and sex‐specific associations. Results After adjustment for confounders, a higher fruit intake at age 8 years was associated with a tendency to reduced odds of prevalent asthma (T3 vs. T1, OR 0.78; 95% CI 0.60–1.01, p‐trend .083), with reduced odds of incident asthma and increased odds of remittent asthma (≥median, OR 0.76; 95% CI 0.58–0.99 and OR 1.60; 95% CI 1.05–2.42, respectively) up to 24 years. Comparable, but non‐significant, odds ratios were observed in analyses of long‐term fruit intake (mean intake at ages 8 and 16 years). In contrast, no association was observed with vegetable intake. A higher dietary TAC (T3 vs. T1) at 8 years was associated with reduced odds of prevalent asthma (OR 0.73; 95% CI 0.58–0.93, p‐trend .010) and improved lung function development (FEV1‐z +0.11; 95% CI 0.01–0.21, p‐trend .036 and FVC‐z +0.09; 95% CI −0.01–0.20, p‐trend .072) up to 24 years. Associations were more pronounced among males, and regarding asthma, participants sensitized to aeroallergens. Conclusions Antioxidant intake in school age may improve asthma and lung function up to young adulthood. Although our results should be interpreted with caution, they emphasize the importance of following current dietary guidelines regarding consumption of antioxidant‐rich foods as part of a balanced diet. This longitudinal study of 2506 participants from the population‐based birth cohort BAMSE aimed to investigate the association of fruit, vegetable and dietary total antioxidant capacity (TAC) at age 8 years, with repeated measures of asthma and lung function up to 24 years. Diet and asthma were assessed by questionnaires and lung function by spirometry. Results from this study suggest that high fruit and dietary antioxidant intake in school age may improve asthma and lung function up to young adulthood.