Lifestyle patterns, dietary intakes and body compositions of Korean female nursing students and their relations to bone mineral density

Abstract

Osteoporosis is one of the leading global health problems with no definitive cure available. It is usually diagnosed when one has fracture due to dramatically decreased bone mineral density (BMD). Peak bone mass (PBM) is established during ones late-20s. Once PBM is reached, the BMD slowly deteriorates over lifetime period. Therefore, an effort to maximize PBM should be established for osteoporosis prevention. It has been reported that lifestyle patterns, dietary intakes and body compositions have effects on BMD formation. Therefore, this study aims to describe Korean female nursing students current BMD, lifestyle patterns, dietary intakes, body compositions and their relations to BMD. A total of 160 female students attending to a nursing school at a college in Seoul, Korea were evaluated. Data collection took place from June 10th to October 25th of 2013. An ultrasonometer was used to determine BMD, one-on-one interview, survey, 24-hour recall and food diary methods were used to determine general characteristics, past and current lifestyle patterns and dietary intakes. An InBody 720 machine was used to analyze body compositions. Data were analyzed using Windows SPSS 20.0 program. The results are as of the followings: The average BMD (t-score) of the students was 0.37 (±1.26), and among these students 128 (80%) was in the normal range and 32 (20%) were in the below the normal range. Currently, 59 students (36.9%) were involved in regular exercise, and they spend about 1.25 (±1.58) times per week on exercising and spent 11.6 (±9.17) hours per week on outdoor activities. When students were divided into a high frequency group (>5h/wk) and a low frequency group (≤5h/wk) according to their past and current exercise hours, the number of students in the high frequency group were as of the followings: elementary school (71, 44.4%), middle school (43, 26.9%), high school (22, 13.8%) and current (24, 15%). Students were divided into 3 groups according to the analysis of their food diaries: adequate, deficient and excessive. A total of 137 (85.6%) students had excessive sodium intakes and 86 (53.8%) had excessive cholesterol intakes. However, 109 (68.1%) had adequate fiber intake and 81 (50.6%) had adequate vitamin C intakes. Vitamin D deficiency was noted in 104 (65%) students, and calcium deficiency was noted in 84 (52.5%) students. As for the body composition, the average BMI of the students, an indicative of their nutritional status, was 21.3kg/m2 (±1.97). The students were divided into 3 groups according to their BMIs: normal (115, 71.8%), underweight (11, 6.9%) and overweight (34, 21.3%). When the students were divided into normal BMD and below the normal BMD groups, variables that showed significant findings are as of the followings. Among lifestyle patterns, weekly exercise frequency (p=.05) and daily caffeine consumption (p=.07) showed significant differences between the groups. Also, weekly exercise hours during elementary school (p=.07), milk consumption during high school (p=.05) and current days (p=.02), and current breakfast consumption (p=.07) showed significant BMD differences. Only vitamin B5 (p=.07) and copper (p=.03) were significant among nutrients analyzed from the dietary intakes. As for the body compositions, BMI (p=.06) and height (p=.03) showed significant differences. This study showed that despite the fact that exercise frequency and caffeine consumption have effects on BMD, a large number of Korean female nursing students were not engaged in regular exercise and were consuming about 2 cups of caffeine daily. Although past and current milk intakes have a positive effect on BMD, our subjects showed a decreasing trend in milk consumption as they progressed from childhood into the adulthood. More than half of the subjects had excessive intakes of sodium and cholesterol that are known to have negative effects on general health. Also, more than half of the subjects had deficiency in vitamin D and calcium intakes. Therefore, in order to strengthen Korean female college students BMD, there is a need for comprehensive interventional programs that reinforces regular exercise, reduces caffeine, sodium and cholesterol intakes, and increases milk, breakfast, vitamin D and calcium intakes.