發展三項健康飲食指標評估臺灣北部地區青少年與母親飲食質量

Abstract

青少年正值兒童至成人期的轉換階段，此階段飲食營養需供應青春期的生長及發育，同時也奠定成年後的飲食習慣及健康基礎，但國民營養健康狀況變遷調查數度指出青少年的營養狀態及飲食攝取不甚理想。良好的飲食質量能滿足個體的營養需求也會影響到孩童的生長發育，甚至降低罹患慢性疾病的風險，因此本研究欲從飲食質量的層面探討青少年飲食表現，包含飲食變化性(dietary diversity)、飲食多樣性(dietary variety)及飲食品質(dietary quality assessment method)，並進一步分析影響青少年飲食質量的相關因素。 受訪者為本研究室民91及93世代中124對青少年及其母親，於青少年11-15歲間每年收集其24小時飲食回憶，歷年共累積257份有效問卷。為更符合本土的飲食習慣及建議，本次將以臺灣每日飲食指南為基礎建立三種不同的飲食質量指標：飲食變化性分數(DDS)、臺灣健康飲食多樣性指標(TW HFD-index)及臺灣健康飲食指數2015版(HEI-2015-NTNUR)，並以此分別評估青少年及其母親的飲食變化性、飲食多樣性及飲食品質。 研究結果顯示，11-15歲間男性身高年變化量顯著高於女性且男女性身高及體重在14歲後具有顯著差異。青少年發育方面，女性初經年齡(中位數11.8歲)早於男性變聲年齡(中位數12.9歲)。另外，女性初經年齡與BMI呈顯著負相關(r = -0.32, p< 0.05)。飲食部分，母親及青少年於追蹤期間營養素攝取量大多維持穩定，但青少年及母親歷年平均的平均營養素足量比分別僅達0.67及0.62，有營養素攝取缺乏(< 70% DRIs)的情形。 飲食質量方面，青少年歷年平均飲食變化性分數為4.36 ± 0.72，飲食多樣性0.46 ± 0.06，飲食品質51.30 ± 6.21，飲食質量表現隨年齡上升顯著變差；母親表現則歷年持平，飲食變化性分數為4.34 ± 0.85，飲食多樣性0.47 ± 0.06，飲食品質53.62 ± 8.94。各評估項目中，全榖雜糧類、奶類與水果類得分最低。母子間營養素攝取量及飲食質量具顯著正相關(r = 0.19-0.54, p < 0.05)，可見青少年飲食深受母親影響，但隨青少年年齡上升，母子間飲食相關性有減弱的趨勢。 青少年及母親飲食質量與多數營養素攝取量及足量比呈顯著正相關(r = 0.18-0.65, p < 0.05)，能適度反應營養素攝取情形。與體位的相關性，青少年的飲食質量與身高年變化量呈顯著正相關(r = 0.24-0.31, p < 0.05)，而飲食質量對青少年及母親現階段體位無顯著影響。分析影響飲食質量的相關因素，青少年睡眠時間及母親飲食質量表現對青少年飲食質量有正向影響；母親僅職業對其飲食品質具顯著影響力。 綜上所述，良好的飲食質量確實能使個體攝取較充足的營養素，也有助於青少年身高增長。另外也發現隨青少年年齡增加，與母親飲食相關性減弱，顯示除提供主要照顧者飲食教育外，也應特別針對青少年進行營養教育，以增進其飲食質量表現。

Adolescence is the period of transition between childhood and adulthood and serves the critical foundation of dietary habit and health development. However, nutritional inadequacy mentioned by Nutrition and Health Survey in Taiwan for adolescents. High dietary quality can meet individual nutritional requirements, promote growth in childhood and decrease risks of chronic diseases in adulthood. The aims of study are to estimate dietary quality, including dietary diversity, dietary variety and dietary quality assessment method, and examine related factors for dietary quality of adolescents and their mothers. Total 124 mother-child dyads participated in two prospective cohort studies from 2002 and 2004 were included. These subjects provided 257 questionnaires, including 24-hour dietary recall for children from 11 to 15 years old. We constructed three dietary indices based on current Taiwan dietary guidelines. In this study, we used dietary diversity score (DDS), Taiwan Healthy Food Diversity index (TW HFD-index) and Healthy Eating Index-2015-National Taiwan Normal University Revised (HEI-2015-NTNUR) to examine dietary quality for adolescents and their mothers. The average for height velocity of boys was higher than the girls during the following period and their height and weight had significantly different after 14 years old. The timing of secondary sex characteristics was earlier in girls (median age = 11.8) than boys (median age = 12.9), and there was a significantly negative correlation (r = -0.32, p< 0.05) between menarche time and BMI for girls. The nutrient intakes remain non-significant (p for trend>0.05), but the mean adequate ratio (MAR) was only 0.67 and 0.62 from 11 to 15 years old for adolescents and their mothers, respectively. These results indicated that most of them had a problem about nutrient inadequacy (< 70% DRIs). For the dietary quality, the mean and standard deviation score was 4.36 ± 0.72 for DDS, 0.46 ± 0.06 for TW HFD-index and 51.30 ± 6.21 for HEI-2015-NTNUR in adolescents. The mean and standard deviation of the dietary quality score for mothers was 4.34 ± 0.85, 0.47 ± 0.06 and 53.62 ± 8.94 separately. Dietary quality declined significantly for adolescents from 11 to 15 years old, but not for their mothers. We observed that the scores of grains, dairy and fruits intake were particularly low in total 7 food groups. There were low to moderate positive correlations (r = 0.19-0.54, p< 0.05) of nutrients intakes and dietary quality scores between adolescents and their mothers. In other words, the diet for adolescents were strongly influenced by their mothers, but the correlation weakened when adolescents getting older. We found that all three dietary quality scores had significantly positive correlations (r = 0.18-0.65, p < 0.05) with most of nutrients and nutrient adequacy ratio (NAR) scores. Moreover, dietary quality score had a significantly positive correlation (r = 0.24-0.31, p < 0.05) with annual height velocity for adolescents, but it didn’t affect body weight of adolescents and their mothers from 11 to 15 years old. For the related lifestyle factors, we found that the sleep duration for adolescents and the three dietary quality scores for mothers had significant positive effects on the three dietary quality scores for adolescents, but only the occupation had significant impact on HEI-2015-NTNUR score for mothers. In conclusion, high dietary quality can helpto consume adequate nutrients and promote height growth for adolescents. In addition, dietary correlation between adolescents and their mothers decreased with the age of the adolescents. To improve dietary quality of adolescents, we suggest nutrition education should be provided for adolescents themselves in addition to their care givers.