Price discounts on low energy dense foods on food intake and health status

The objective of this study was to observe the effects of a multi-level (30%, 15%, and 0%) randomized discount on fruits, vegetables, and non-caloric beverages on changes in dietary intake. This randomized controlled trial (RCT) comprised an 8-week baseline, a 32-week intervention, and a 16-week follow-up. 24-hour dietary recalls were conducted during the baseline period and before the intervention midpoint. In-person clinical measures were analyzed from Week 8 (end of baseline) and 24 (midpoint). This report is from an interim analysis up to the intervention period midpoint at Week 24, as the study is still ongoing. Participants with BMIs of 24.5-50 kg/m2 and ages 18-70 years old who were the primary household shoppers were recruited from several New York City supermarkets, starting in September 2018. Of these, we analyzed 20 in the 30% discount group, 25 in the 15% discount group, and 19 in the 0% discount group. The 30% discount group reported greater intake of vegetables (+98.4 g ± 48.9 SD, P = 0.049) and diet soda (+63.3 g ± 29.3, P = 0.035) relative to the baseline period, compared to the 0% discount group. The clinical measures including body weight remained unchanged. The participants who experienced the COVID-19 pandemic had a marginal increase in body weight of 1.5 kg, P = 0.053. In conclusion, we observed a significant increase in intake of vegetables and diet soda in the 30% discount group relative to the 0% discount group.本研究旨在探究多级（30%、15%及0%）随机折扣对水果、蔬菜及无热量饮料的膳食摄入变化的影响。本随机对照试验（randomized controlled trial, RCT）包含8周基线期、32周干预期与16周随访期。研究于基线期及干预期中点前开展24小时膳食回顾调查；于第8周（基线期末）及第24周（干预期中点）采集并分析实地临床测量数据。本报告为截至干预期第24周中点的中期分析结果，因研究仍在进行中。招募对象为体质指数（Body Mass Index, BMI）24.5~50 kg/m²、年龄18~70岁的家庭主要购物者，招募工作于2018年9月起在纽约市多家超市启动。最终纳入分析的受试者包括：30%折扣组20人、15%折扣组25人、0%折扣组19人。数据分析结果显示，相较于0%折扣组，30%折扣组的蔬菜摄入量较基线期显著提升（+98.4 g ± 48.9 SD，P=0.049），无糖苏打水摄入量亦较基线期显著提升（+63.3 g ±29.3 SD，P=0.035）。包括体重在内的各项临床测量指标未出现显著变化。受新冠疫情影响的受试者体重小幅上升1.5 kg（P=0.053）。综上，本研究观察到相较于0%折扣组，30%折扣组的蔬菜与无糖苏打水摄入量出现显著提升。