Department of Human Nutrition, University of Otago, PO Box 56, Dunedin 9054, New Zealand.
Nutr J. 2013 Apr 24;12:51. doi: 10.1186/1475-2891-12-51.
Associations between food choice and body composition in previous studies of adolescents have been inconsistent. This may be due to the body composition measures used, or these associations may be affected by the dieting status of adolescents. The objective of this study was to investigate the association between dietary patterns and body composition in adolescents, and determine if these associations are moderated by dieting status.
Information on food consumption and current dieting status was collected, using a web-based survey, in 681 adolescents (mean age 15.8 (SD 0.9) years) from schools in Otago, New Zealand. Non-dieters were defined as those reporting not being on a diet as they were "happy with their weight". Principal components analysis (PCA) was used to determine dietary patterns. Body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), fat mass index (FMI), and fat-free mass index (FFMI) were examined as outcomes. Generalized estimating equations were used to examine associations between dietary patterns and body composition.
PCA produced three dietary patterns: 'Treat Foods', 'Fruits and Vegetables', and 'Basic Foods'. A standard deviation increase in 'Basic Foods' was associated with a 3.58% decrease in FMI (95%CI -6.14, -0.94) in the total sample. When separate sex analysis was undertaken significant negative associations were found in boys only, between the 'Basic Food' score and WC, WHtR, FMI, and FFMI, while the 'Fruits and Vegetables' pattern was negatively associated with FMI. Associations between 'Treat Foods' and BMI, WC, and WHtR in non-dieters were positive, while these associations were negative for all other participants.
Significant associations were found between dietary patterns and indices of both central and total adiposity, but not BMI. Therefore using only BMI measures may not be useful in this age group. Since our results were significant for boys and not girls, nutrition messages designed to prevent obesity may be particularly important for adolescent boys. As an interaction between dieting status and 'Treat Foods' existed, future studies should also explore the role of dieting when investigating food choice and body composition.
以往青少年的食物选择与身体成分的研究结果并不一致。这可能是由于所使用的身体成分测量方法不同，或者这些关联可能受到青少年节食状态的影响。本研究的目的是调查青少年饮食模式与身体成分之间的关系，并确定这些关联是否受到节食状态的调节。
在新西兰奥塔哥的学校，通过网络调查收集了 681 名青少年（平均年龄 15.8（0.9）岁）的食物消费和当前节食状态信息。非节食者被定义为那些报告自己“对体重满意”而不节食的人。采用主成分分析（PCA）确定饮食模式。将体重指数（BMI）、腰围（WC）、腰高比（WHtR）、脂肪质量指数（FMI）和去脂体重指数（FFMI）作为研究结果。采用广义估计方程检验饮食模式与身体成分之间的关系。
PCA 产生了三种饮食模式：“款待食品”、“水果和蔬菜”和“基础食品”。在总样本中，“基础食品”的标准差增加与 FMI 降低 3.58%（95%CI -6.14，-0.94）相关。当进行单独的性别分析时，仅在男孩中发现“基础食品”得分与 WC、WHtR、FMI 和 FFMI 之间存在显著负相关，而“水果和蔬菜”模式与 FMI 呈负相关。非节食者中，“款待食品”与 BMI、WC 和 WHtR 之间存在正相关，而对于所有其他参与者，这些关联则为负相关。
饮食模式与中心和总体肥胖的指标之间存在显著关联，但与 BMI 无关。因此，仅使用 BMI 测量可能对该年龄组不适用。由于我们的结果仅在男孩中显著，而在女孩中不显著，因此设计用于预防肥胖的营养信息可能对青少年男孩尤为重要。由于节食状态与“款待食品”之间存在交互作用，因此未来的研究还应在研究食物选择与身体成分时探讨节食的作用。
