Integrating dietitians' perspectives and behavioral efficacy into food-based dietary guidelines implementation

Area of Science:

• Nutrition Science
• Public Health
• Behavioral Science

Background:

• Diet-related non-communicable diseases pose a significant public health challenge.
• Diet quality is influenced by socioeconomic factors, and current dietary guidelines often lack behavioral impact.
• Translating guidelines into everyday eating, especially in low-involvement contexts, remains difficult.

Purpose of the Study:

• To investigate how dietitians operationalize dietary guidelines in portion-size counseling.
• To determine if different guideline formats influence food intake in a real-world setting.
• To optimize the design of food-based dietary guidelines for improved actionability.

Main Methods:

• Study 1: Survey of 441 French dietitians on portion size and consumption timeframe communication.
• Study 2a: Randomized cafeteria field experiment (n=336) comparing three graphic guideline designs with a control.
• Study 2b: Online experiment (n=201) assessing processing fluency of guideline formats.

Main Results:

• Dietitians predominantly use concrete, meal-level cues for portion advice, not grams.
• A food-group design with clear imagery and concise daily guidance reduced energy selection and intake in a cafeteria setting.
• The optimal format balanced visual richness with ease of processing, achieving moderated fluency.

Conclusions:

• Food-based dietary guidelines are more actionable when aligned with dietitians' practical language and presented with balanced visual appeal and processing ease.
• Involving dietitians in guideline development and conducting real-world trials are crucial for policy implications.
• Tailoring guideline graphics to specific dietary contexts can enhance their effectiveness.