Antioxidant vitamin intakes assessed using a food-frequency questionnaire: correlation with biochemical status in smokers and non-smokers

Abstract

The increasing interest in the possible role of antioxidant vitamins in many disease states means that methods of assessing vitamin intakes which are suitable for large-scale investigations are now required. The suitability of the food-frequency questionnaire, which was developed by the Medical Research Council -Cardiff Group, for determining dietary intake of antioxidant vitamins in epidemiological studies was investigated in 196 Scottish men. The validity of the dietary data was assessed by comparison with serum vitamin concentrations, and separate analyses were performed for current smokers and nonsmokers. The results showed that total energy intake and the percentage of energy derived from sugar were higher in smokers, and that both dietary and serum values of vitamin C, /I-carotene and vitamin E were lower in smokers than non-smokers. After adjustment for serum lipids, energy intake and body mass index, correlation coefficients between dietary and serum vitamins C and E were similar for smokers (r 0555 and 0.25 respectively) and non-smokers (r 0.58 and 0.32 respectively). Correlation between dietary and serum carotenes was reduced from 0.28 in non-smokers to 0.09 in smokers and correlations for retinol and total vitamin A were weakly significant only for non-smokers. The food-frequency questionnaire assigned > 70% of subjects correctly into the upper or lower plus adjacent tertiles of serum vitamin values, with the exception of @-carotene and total vitamin A for smokers. Thus, the foodfrequency questionnaire appeared to be an adequate tool for assigning individuals into tertiles of serum antioxidant vitamins with the main exception of &carotene for smokers. Marked differences do occur between the vitamins and between the smoking groups which may reflect reduced accuracy of reporting on the food-frequency questionnaire or differential absorption and metabolism of the vitamins. Dietary antioxidant vitamins: Biochemical markers: Smoking

Effects of smoking and smoking cessation on dietary habits of a Swiss urban population

“…Values are slightly different than preferably``from those'' in Table 2 because the model does no include current smokers. Bolton-Smith et al, 1991Strickland et al, 1992;Thornton et al, 1994;Margetts & Jackson, 1993;Morabia & Wynder, 1990;Subar et al, 1990;Midgette et al, 1993). The diminution of total carbohydrates intake and of antioxidants such as betacarotene in heavy smokers has been observed in British smokers (Margetts & Jackson, 1993) whereas a diminution of saccharose consumption had been noted in Australian female smokers (Midgette et al, 1993).…”

“…It has been hypothesized that the effect of nicotine on smell and taste leads smokers to prefer meat and fatrich foods instead of fruits or vegetables (Redington, 1984;Grunberg, 1982;Perkins et al, 1990;Frye et al, 1990). Indeed, there is evidence that, after smoking cessation, diet changes and becomes more similar to that of never smokers (Cade and Margetts, 1991;Hebert & Kabat, 1990;Curtin et al, 1997;Bolton-Smith et al, 1991Strickland et al, 1992;Thornton et al, 1994;Morabia & Wynder, 1990;Midgette et al, 1993).…”

Low muscle mass in older men: The role of lifestyle, diet and cardiovascular risk factors

“…Dietary intake data were obtained using a food frequency questionnaire; development and validation have been described (19)(20)(21). Participants reported usual frequency of consumption of 86 food and drink types.…”

“…several exposure variables were based on self-reports, so misclassification was possible. However, previous food frequency questionnaire validation reduces the risk of bias for dietary variables (19)(20)(21).…”

Associations between dietary flavonoid intakes and bone health in a scottish population

“…(3,5) The FFQ quantifies intakes of 98 foods in the present and past (up to 12 years and 20 to 30 years of age) and has been validated using biochemical markers of antioxidant status and 7-day weighed records. (20,21) Dietary flavonoid intakes of the foods were calculated using a nutrient database that was validated for use with an earlier version of the FFQ. (22) When nutrient information was missing (eg, for cooked vegetables), the US Department of Agriculture (USDA) database was consulted.…”