食品加固,或者获取食物的动机,可以预测选择和消费。蔬菜消费量远低于成人的推荐量,因此,了解如何增加蔬菜强化可以为如何增加消费提供有价值的见解。
我们试图确定每日食用美国人饮食指南(DGA)推荐的蔬菜摄入量是否会导致超重和肥胖成年人对蔬菜强化的敏感性。
BMI≥25kg/m2的健康成年人,每天食用≤1杯当量蔬菜,被随机分配到蔬菜干预组(VI;n=55)或注意力对照组(AC;n=55)。VI包括每天提供DGA建议的数量和类型的蔬菜(〜270克/天),持续8周。参与者再随访8周以评估持续消费。通过共振拉曼光散射光谱法(RRS)每周测量顺应性。使用计算机选择范例在第0、8、12和16周测试蔬菜补强。
在VI组中,RRS强度从第0周增加到第8周(从22,990增加到37,220),在第16周恢复到基线(27,300)。在AC组中没有观察到变化。处理(P=0.974)和时间(P=0.14)对蔬菜强化没有主要影响,处理x时间交互作用(P=0.44)。性别没有调节作用(P=0.07)。年龄(P=0.60),BMI(P=0.46),延迟贴现(P=0.24),6-正丙基硫氧嘧啶品尝者状态(P=0.15),或膳食对蔬菜强化变化的抑制作用(P=0.82)。
这些研究结果表明,提供多种蔬菜以满足DGA建议8周对蔬菜强化没有影响,并强调了增加成人蔬菜消费的困难。该试验在clinicaltrials.gov注册为NCT02585102。
Food reinforcement, or the motivation to obtain food, can predict choice and consumption. Vegetable consumption is well below recommended amounts for adults, so understanding how to increase vegetable reinforcement could provide valuable insight into how to increase consumption.
We sought to determine whether daily consumption of the Dietary
Guidelines for Americans (DGA) recommendations for vegetable intake induces sensitization of vegetable reinforcement in adults with overweight and obesity.
Healthy adults with a BMI ≥ 25 kg/m2 who consumed ≤1 cup-equivalent of vegetables/day were randomly assigned to a vegetable intervention (VI; n = 55) or an attention control (AC; n = 55) group. The VI consisted of the daily provision of vegetables in the amounts and types recommended by the DGA (∼270 g/day) for 8 weeks. Participants were followed for an additional 8 weeks to assess sustained consumption. Compliance was measured weekly by resonance Raman light-scattering spectroscopy (RRS). Vegetable reinforcement was tested at weeks 0, 8, 12, and 16 using a computer choice paradigm.
In the VI group, RRS intensity increased from week 0 to 8 (from 22,990 to 37,220), returning to baseline by week 16 (27,300). No change was observed in the AC group. There was no main effect of treatment (P = 0.974) or time (P = 0.14) and no treatment x time interaction (P = 0.44) on vegetable reinforcement. There was no moderating effect of sex (P = 0.07), age (P = 0.60), BMI (P = 0.46), delay discounting (P = 0.24), 6-n-propylthiouracil taster status (P = 0.15), or dietary disinhibition (P = 0.82) on the change in vegetable reinforcement.
These findings suggest no effects of the provision of a variety of vegetables to meet DGA recommendations for 8 weeks on vegetable reinforcement and highlight the difficulty in increasing vegetable consumption in adults. This trial was registered at clinicaltrials.gov as NCT02585102.