Dietary maximum exposure assessment of vitamins and minerals from various sources in Korean adolescents / 한국영양학회지

Dietary supplement use is prevalent and represents an important source of nutrition. This study was conducted in order to assess the dietary maximum exposure of vitamins and minerals from various sources including regular diet, vitamin.mineral supplements for non-prescription drug (VMS-NPD), vitamin.mineral supplements for health functional foods (VMS-HFF), and fortified foods (FF). A total of 1,407 adolescent boys and girls attending middle or high schools were chosen from various cities and rural communities in Korea. Users of vitamin and mineral supplements (n = 60, 15-18 years of age) were chosen from the above 1,407 students. Intake of vitamins and minerals from a regular diet and FF was assessed by both food record method and direct interview for three days of two weekdays and one weekend, and those from VMS-NPD and VMS-HFF were assessed by both questionnaire and direct interview, and compared with the recommended nutrient intake (RNI) and the tolerable upper intake level (UL) for Korean adolescents. Daily average exposure range of vitamins and minerals from a regular diet was 0.3 to 4.4 times of the RNI. Some subjects had an excessive exposure to the UL in the following areas: from regular diets, vitamin A (1.7%) and niacin (5.0%); from only VMS-NPD, vitamin C (9.1%) and iron (5.6%); and from only VMS-HFF, niacin (8.6%) > vitamin B6 (7.5%) > folic acid (2.9%) > vitamin C (2.3%). Nutrients of daily total intake from regular diet, VMS-NPD, VMS-HFF, and FF higher than the UL included nicotinic acid for 33.3% of subjects, and, then, in order, vitamin C (26.6%) > vitamin A (13.3%), iron (13.3%) > zinc (11.7%) > calcium (5.0%) > vitamin E (1.7%), vitamin B6 (1.7%). Thus, findings of this study showed that subjects may potentially be at risk due to overuse of supplements, even though most of them took enough vitamins and minerals from their regular diet. Therefore, we should encourage adolescents to have sound health care habits through systematic and educational aspects.

Prevalence of vitamin, mineral supplement use and its related factors among Korean adolescents / 한국영양학회지

This study is conducted in order to investigate the prevalence of vitamin, mineral (VM) supplement use and its related factors among Korean adolescents. Using a cross-sectional study design, information was obtained by questionnaires from adolescents selected by stratified sampling in large, small and middle-size cities, as well as rural areas of the whole country, followed by convenience sampling. The total number of participants in this study was 1,407 adolescents (15.2 +/- 1.6 years) attending middle or high schools, chosen from various cities and rural areas in Korea. The prevalence of VM supplement use was 65.5%, and there was no significant difference between the genders. City dwellers took VM supplements more frequently than those adolescents from rural areas (p < 0.01). The VM supplement users tended to have higher family income, parents' academic background, and socioeconomic status, respectively (p < 0.001). The greater part of VM supplement users replied that they acquired their nutritional information from their parents, relatives and friends, while many nonusers replied that they did it from school classes (p < 0.05). Compared to nonusers, VM supplement users had greater 'self concern about health' (p < 0.05), 'parents' concern about child's health, growth, and nutritional intake' (p < 0.001), and 'parents' concern about child's grade point' (p < 0.01). However, there was no significant difference between users and nonusers when it came to 'self perception of body shape' or 'BMI'. In addition, users significantly had greater nutritional beliefs concerning VM supplements than nonusers (p < 0.001). These results showed that VM supplement use has been common among adolescents in Korea, and supplement use of subjects has been related with various factors. Among them, it was shown that especially parents great influence the use of VM supplements by adolescents. Thus, not only education for adolescents, but also that for parents is needed to help adolescents take VM supplements properly.