The SWITCH Dietary and Behavioural Intervention Study

Behavioral support is designed to help participants adhere to the dietary recommendations through personalized coaching and motivational strategies. Participants engage in weekly or bi-weekly coaching sessions, either online or in person, where they receive guidance on overcoming challenges and maintaining dietary changes. The coaching incorporates evidence-based behavior change techniques, such as goal setting, self-monitoring, feedback on performance, problem-solving, and stimulus control. To further support behavior change, participants receive practical tools, including visual aids, educational videos, and structured meal planning resources. The overall goal of behavioral support is to encourage sustainable dietary habits by providing continuous encouragement and individualized strategies.

Food support, which is provided exclusively to participants in the Optimized Lifestyle Intervention Group, ensures that they have access to key foods required to meet dietary targets. These foods include whole grains such as whole grain bread, oats, and pasta; vegetables in both fresh and frozen forms; fruits and berries, including apples, pears, and frozen berries; legumes such as lentils, beans, and chickpeas; and seafood, including fatty fish, lean fish, and mussels. To facilitate adherence, participants also receive recipes and meal plans that incorporate these foods. Some fresh food items are made available at supermarkets near participants' residences to improve accessibility and convenience. Food support aims to reduce barriers to dietary change by ensuring that participants have the necessary ingredients to follow the SWITCH diet effectively.

Dietary advice consists of a simple document outlining the SWITCH diet, which is based on European and Nordic dietary guidelines. Participants receive this information in written form without any additional guidance, counseling, or support. The SWITCH diet emphasizes increased consumption of whole grains, vegetables, fruits, legumes, and seafood while limiting processed foods, added sugars, and excessive salt.