Serum tocopherol levels and vitamin E intake are associated with lung function in the normative aging study.
Clin Nutr. 2015 Feb 7. Epub 2015 Feb 7. PMID: 25715694
BACKGROUND & AIMS: The results of studies assessing relationships between vitamin E intake and status and lung function are conflicting. This study aimed to evaluate the effect of vitamin E intake and serum levels of tocopherol isoforms on lung function in a cross-sectional sample of 580 men from the Normative Aging Study, a longitudinal aging study.
METHODS: Regression models were used to look at associations of serum tocopherol isoform levels and vitamin E intake with lung function parameters after adjustment for confounders. Vitamin E intake was measured using a food frequency questionnaire and serum levels ofγ, α, and δ-tocopherol levels were measured using high-performance liquid chromatography.
RESULTS: After adjustment for potential confounders, serumγ-tocopherol had a significant inverse association with forced vital capacity (β = -0.10, p = 0.05). Alpha and δ-tocopherol were not associated with any lung function parameter. After classifying COPD status according to Global Initiative for Obstructive Lung Disease (GOLD) stage criteria, serum levels of δ-tocopherol were lower in participants with more severe COPD (p = 0.01). Serum levels of δ-tocopherol were also lower in participants with greater levels of smoking (p = 0.02). Both vitamin E intake (β = 0.03, p = 0.02; β = 0.03, p = 0.01) and use of vitamin E supplements (β = 0.05, p = 0.03; β = 0.06. p = 0.02) were positively associated with FEV1 and FVC, after adjusting for confounders. Subjects who took vitamin E supplements had significantly higher α-tocopherol levels (p < 0.0001) and lower γ-tocopherol levels (p < 0.0001) than non-users.
CONCLUSION: In this study, there is a positive association between dietary vitamin E intake and lung function, and evidence of an inverse relationship between serum levels ofγ-tocopherol and lung function.