Monteiro Sofia, Pujol-Busquets Georgina, Smith James, Larmuth Kate
Global Health Research Group, Kiel Institute for the World Economy, Kiel, Schleswig-Holstein, Germany.
Faculty of Health Sciences, Universitat Oberta de Catalunya (Open University of Catalonia, UOC), Barcelona, Catalonia, Spain.
PLoS One. 2025 Apr 8;20(4):e0319503. doi: 10.1371/journal.pone.0319503. eCollection 2025.
There is reasonable concern that self-reported nutrition assessments do not reflect actual food choices. Yet, a correspondence between both is imperative to evaluate any intervention on food preferences. This paper makes such a comparison. It provides evidence from a low-carbohydrate nutrition education program, which is assessed with both surveys and an incentivized behavioral measure of food choice. The main result is that there is a large correspondence between survey and behavioral measures for our sample of 95 women from two historically underprivileged communities in the Western Cape, South Africa. Compared to the control, the treatment group reported a 35% lower intake from the high-carbohydrate/ ultra-processed food Red List and 60% higher intake from the low-carbohydrate whole foods Green List. The treatment group was also 40% less likely to buy anything from the Red List with a supermarket voucher. In terms of the Green List, the treatment group was significantly more likely to buy eggs, organ meat, traditional fats, avocado and fish but there was no difference in red meat and chicken, non-starchy vegetables and full cream dairy. Low-cost incentivized measures of revealed preferences can be designed to validate subjective habits, increasing confidence in the quality of evidence from nutrition intervention studies.
人们有理由担心自我报告的营养评估不能反映实际的食物选择。然而，两者之间的对应关系对于评估任何关于食物偏好的干预措施来说是必不可少的。本文进行了这样的比较。它提供了来自一个低碳水化合物营养教育项目的证据，该项目通过调查和一种激励性的食物选择行为测量方法进行评估。主要结果是，对于我们从南非西开普省两个历史上处于弱势的社区抽取的95名女性样本，调查和行为测量之间存在很大的对应关系。与对照组相比，治疗组报告称，来自高碳水化合物/超加工食品“红名单”的摄入量降低了35%，来自低碳水化合物全食物“绿名单”的摄入量提高了60%。治疗组使用超市代金券从“红名单”购买任何东西的可能性也降低了40%。就“绿名单”而言，治疗组购买鸡蛋、内脏肉、传统脂肪、鳄梨和鱼的可能性显著更高，但在红肉和鸡肉、非淀粉类蔬菜和全脂乳制品方面没有差异。低成本的显示偏好激励措施可以设计用来验证主观习惯，增强对营养干预研究证据质量的信心。
