Purpose

Randomised controlled trials identify causal links between variables but not why an outcome has occurred. This analysis sought to determine how psychological factors assessed at baseline influenced response to personalised nutrition.

Design/methodology/approach

Web-based, randomised, controlled trial (RCT) was conducted across seven European countries. Volunteers, both male and female, aged over 18 years were randomised to either a non-personalised (control) or a personalised (treatment) dietary advice condition. Linear mixed model analysis with fixed effects was used to compare associations between internal and external health locus of control (HLoC), nutrition self-efficacy (NS-E) and self-report habit index (S-RHI) at baseline (N = 1444), with healthy eating index (HEI) and Mediterranean diet index (MDI) scores between conditions post-intervention (N = 763).

Findings

An increase in MDI scores was observed between baseline and six months in the treatment group which was associated with higher NS-E (p < 0.001), S-RHI (p < 0.001) and external HLoC (p < 0.001). Increase in HEI between baseline and six months in the treatment group was associated with higher NS-E (p < 0.001) and external HLoC (p = 0.009). Interaction between time and condition indicated increased HEI scores (p < 0.001), which were associated with higher S-RHI scores in the treatment than control group (p = 0.032). Internal HLoC had no effect on MDI or HEI.

Originality/value

Psychological factors associated with behaviour change need consideration when tailoring dietary advice. Those with weaker habit strength will require communication focussed upon establishing dietary habits and support in integrating advised changes into daily routine. Information on habit strength can also be used to inform how progress towards dietary goals is monitored and fed back to the individual. Those with stronger habit strength are more likely to benefit from personalised nutrition.

中文翻译：

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自我效能、习惯强度、健康控制点和对个性化营养 Food4Me 干预研究的反应

目的

随机对照试验确定变量之间的因果关系，但不确定结果发生的原因。该分析试图确定基线评估的心理因素如何影响对个性化营养的反应。

设计/方法/方法

在七个欧洲国家进行了基于网络的随机对照试验 (RCT)。年龄超过 18 岁的男性和女性志愿者被随机分配到非个性化（对照）或个性化（治疗）饮食建议条件。使用具有固定效应的线性混合模型分析来比较基线时的内部和外部健康控制点 (HLoC)、营养自我效能 (NS-E) 和自我报告习惯指数 (S-RHI) 之间的关联 ( N  = 1444 )，干预后条件之间的健康饮食指数 (HEI) 和地中海饮食指数 (MDI) 得分 ( N  = 763)。

发现

在治疗组的基线和六个月之间观察到 MDI 评分的增加，这与更高的 NS-E ( p  < 0.001)、S-RHI ( p  < 0.001) 和外部 HLoC ( p  < 0.001) 相关。治疗组基线和六个月之间 HEI 的增加与较高的 NS-E ( p  < 0.001) 和外部 HLoC ( p  = 0.009) 相关。时间和条件之间的相互作用表明 HEI 评分增加 ( p  < 0.001)，这与治疗组中 S-RHI 评分高于对照组 ( p  = 0.032) 相关。内部 HLoC 对 MDI 或 HEI 没有影响。

原创性/价值

在定制饮食建议时，需要考虑与行为改变相关的心理因素。那些习惯强度较弱的人将需要专注于建立饮食习惯的沟通，并支持将建议的改变融入日常生活。关于习惯强度的信息也可用于告知如何监测饮食目标的进展并将其反馈给个人。那些习惯强度更强的人更有可能从个性化营养中受益。