The Impact of Financial Incentives on Completion of a No Money No Time 6-Week Culinary Nutrition eHealth Challenge.

Introduction: No Money No Time is a culinary nutrition website focused on diet quality improvement. The aim was to compare participant retention in a 6-week eHealth challenge, with and without use of financial incentives and to compare demographic characteristic, diet quality and engagement outcomes between them.

Methods: The single-arm, pre-post studies [Spring Eatz (30 August to 17 September, 2023) and RE$ET (20th February to March, 2024)] recruited adults ≥ 18 years from Australia into a 6-week nutrition challenge delivered via weekly emails that directed participants to the No Money No Time (NMNT) purpose-built culinary and nutrition-related health website from after completing the embedded Healthy Eating Quiz (HEQ) and consenting to data use for research purposes. At the start of each challenge week participants received an email with links to targeted NMNT content, relevant recipes, plus specific time and cost-efficient advice to help improve dietary patterns. Weeks 2-5 included a prize draw of 4 × AUD$25 eGift cards randomly drawn from participants actively engaging with challenge materials and a week 6 final draw of 4 × AUD$100 eGift cards from participants completing the HEQ and feedback survey post-challenge. Data was collected on diet quality (HEQ score), demographics (gender, age, vegetarian status, number of people/weekly household grocery expenditure, expenditure on food purchased away from the home, weight and height). NMNT website analytics were collected via Active Campaign software.

Results: The incentivised challenge recruited significantly more males (22% vs. 15%) and a younger demographic (mean age 45 y vs. 50 y) compared to unincentivized (p < 0.01). There was a significantly greater 6-week retention in the incentivised challenge compared to no incentivisation (21% vs. 16%, z-score = 2.14, p < 0.05), with significant increases in diet quality (HEQ score) in adjusted models ( + 4.5 points, p < 0.05), which was not significantly different to the unincentivized challenge p = 0.09.

Conclusions: The 6-week eHealth nutrition challenge using financial incentives improved diet quality and led to significantly greater retention compared to an unincentivized challenge, with overall retention still relatively low. Engagement with weekly emails exceeds global email marketing campaigns. Future iterations should incorporate strategies to increase participant engagement. An email campaign represents a low-cost approach to achieve short-term improvement in diet quality.