A Small Nudge for Better Health Through Reduced Salt Intake, Increased Vegetable Intake, and Smaller Portion Size

A healthy diet is an important pillar for public health and for the prevention of several lifestyle diseases (e.g. obesity, cardiovascular diseases). However, diet choices are often not conscious choices. While it may help to make individuals more aware of healthy options for example through education or nutrition labels, it remains difficult for many to eat healthy. The food environment in which choices are made has an impact on the choice. Smart design of the food environment may help individuals to make a healthier choice, by nudging them towards the healthier alternative, while not limiting the availability of the less healthy choice.

This study tests how these 'nudges' can affect food behavior and health of participants in a 4-week rehabilitation course at Feiring Heart clinic. Nudges will be implemented in the cafeteria at the clinic.

Three types of nudges will be tested:

• Salt nudge: aims to reduce salt (sodium) intake. Salt will be less easily available in the cafeteria, and other spices (without sodium) will be made easily available. Food in the buffet that is either very high or very low in salt will be labeled.
• Vegetable nudge: aims to increase vegetable intake. Names of the vegetable dishes in the buffet will be made more attractive, signs will be placed with reminders to eat more vegetables, and with visual indications of the percentage of vegetables that should be part of a meal.
• Portion size nudge: aims to decrease portion size. Smaller plates will be provided, and utensils for self-serving calorie-dense foods in the buffet will be smaller than normal.
• One period will also combine all the nudges described above.

Outcomes include measures of food intake during the 4-week rehabilitation course, and whether food habits 6 weeks and 6 months after the 4-week course have changed, compared to before the course. BMI will be monitored during the 4-week period and self-assessed in the 6 months after. Physical activity habits will be considered during the entire experimental period, and satisfaction with the cafeteria food and service will be monitored throughout to assess whether the nudges impact customer satisfaction.

Results are expected to be transferable to other heart clinics, and cafeterias in other institutions.

Inclusion criteria

• Participants should be part of the 4 week rehabilitation course at the Feiring heart clinic
• Participants should be willing and able to complete the necessary registration of food choices, and the relevant questionnaires

Exclusion criteria

• None