Dietary antioxidant vitamin intake and lung function in the general population.

Abstract

We have investigated the relation between lung function and dietary intake of the antioxidant vitamins C and E in the general population in a cross-sectional survey of a random sample of adults from the electoral register of an administrative area of Nottingham. In 2,633 subjects 18 to 70 yr of age, we measured FEV1 and FVC, allergen skin sensitivity to grass pollen, cat fur, and Dermatophagoides pteronyssinus, pack-years smoking exposure by personal recall, and usual dietary intake of vitamins C and E by semiquantitative food frequency questionnaire. After adjustment for the effects of age, sex, height, mean allergen skin wheal diameter, and pack-years smoking history, both FEV1 and FVC were significantly and independently related to mean daily intake of vitamin C, such that a standard deviation (40 mg/d) higher vitamin C intake was associated with a 25.0 (95% CI, 5.2 to 44.8; p = 0.01) ml higher FEV1 and a 23.3 (0.94 to 45.7, p = 0.04) ml higher FVC. There was also an association between vitamin E intake and lung function, such that a standard deviation (2.2 mg) higher intake of vitamin E was associated with a 20.1 (1.3 to 40.4, p = 0.04) ml higher FEV1 and a 23.1 (1.0 to 45, p = 0.04) ml higher FVC. However, vitamin C and vitamin E intakes were significantly correlated (r = 0.29, p < 0.001), and after allowing for the effects of vitamin C there was no additional independent effect of vitamin E on either FEV1 or FVC.(ABSTRACT TRUNCATED AT 250 WORDS)

Lung function and blood levels of copper, selenium, vitamin C and vitamin E in the general population

“…We have previously reported that FFQ estimates of intake of vitamin C were directly related to FEV 1 in this population (Britton et al, 1995). An association between plasma vitamin C and lung function has also been demonstrated in several other studies (Ness et al, 1996;Hu & Cassano, 2000;Schunemann et al, 2001;Kelly et al, 2003) and is consistent with the hypothesis that increased antioxidant status protects the lungs against loss of lung function.…”

“…The negative finding in relation to vitamin E also corroborates our analysis of data on vitamin E intake in this population (Britton et al, 1995), although the validity of the conclusions based on the analyses of the plasma vitamin E levels is questioned by the fact that we were unable to obtain fasting samples, and do not have estimates of serum cholesterol or triglycerides to adjust for confounding by these variables (Hunter, 1990;Traber & Jialal, 2000). Some (Hu & Cassano, 2000;Schunemann et al, 2001) but not all (Grievink et al, 1999;Grievink et al, 2000) studies have described positive associations between serum vitamin E and lung function, but those that did demonstrate an effect used either fasting samples (Schunemann et al, 2001) or adjusted for serum triglycerides and total cholesterol in their analysis (Hu & Cassano, 2000); and so we are unable to exclude the possibility that our nonfasting samples were insufficient to detect an effect.…”

“…A total of 2633 participants responded and provided complete dietary and lung function data in the original survey, representing between 48 and 59 per cent of those potentially eligible (Britton et al, 1995). Of 528 individuals in the systematic subsample, venous blood was provided by and successfully analysed for plasma vitamin C, vitamin E and copper in 479 (91 per cent), and for serum selenium in 472 (89 per cent) participants.…”

“…Data for the study were taken from participants in a crosssectional survey of diet and lung disease that has been described previously (Britton et al, 1994b(Britton et al, , 1995. Briefly, participants were identified by systematic sampling from the electoral register of a Local Authority Area in Nottingham, and those aged 18-70 y on 1st January 1991 were invited to attend a local General Practice surgery or health centre for a questionnaire assessment and lung function tests.…”

“…In particular, there is epidemiological evidence that a low dietary intake of nutrients that contribute to antioxidant defences increases susceptibility to impaired lung function with no threshold effect, but this evidence relates predominantly to nutrients such as vitamins C (Schwartz & Weiss, 1994;Britton et al, 1995;Grievink et al, 1998;Hu et al, 1998;Chen et al, 2001;Gilliland et al, 2003) and E (Dow et al, 1996;Butland et al, 2000) that can be measured in population studies using self-reported Food Frequency Questionnaires (FFQs). Few studies have looked at the effect of lung function using biological markers of these vitamins, and very little is known of the effects of other antioxidant cofactors that cannot be estimated reliably by FFQ methods, such as selenium and copper (Hunter, 1990).…”