The COVID-19 pandemic affects eating habits, diet quality and physical activity differently among individuals; it is unclear how these behaviours will evolve as the pandemic continues. In this observational study, dietary intake will be frequently collected using an artificial intelligence (AI)-enhanced mobile application combined with real-time analysis, and lifestyle behaviours from online questionnaires, to provide timely, relevant data for public health decision making.

A thousand nine hundred and twenty adult men and women aged 18 years and older, living in the community and owning a smartphone or tablet, will be recruited all over Canada. Rapid recruitment will be achieved using social media and professional networks. All data will be collected online to allow a broad reach even in remote regions. Self-reported eating habits, physical activity, sleep, alcohol consumption, anxiety and depression data will be collected using validated questionnaires on an online survey platform, and dietary intake data using the mobile application Keenoa. With the application, participants take pictures of their meals, which are analyzed and accessible to researchers in real-time, providing comprehensive data on nutrient and food intake, and hence patterns and diet quality. Diet will be tracked for a full week at study entrance and repeated 6 times during a year, and once one year later, along with follow-up questionnaires on lifestyle behaviours.

The main study objectives are 1) to evaluate how eating habits, diet quality and related lifestyle behaviours of Canadian adults are impacted by confinement phases of the pandemic over one year; and 2) determine the association between eating behaviours and diet quality with contextual socio-demographic, education, emotional and health factors, and identify emerging explanatory factors as clusters.

Inclusion Criteria:

• Men and women aged 18 years and over, living in Canada
• Owning a smartphone and having access to internet
• Able to read and understand English or French

Exclusion Criteria:

• Any active and uncontrolled acute disease that interferes with usual food intake
• Being hospitalized
• Pregnancy or lactation

Approximately 1,920 adult men and women will be recruited from several regions of Canada, and stratified by age (18-45 y, 45-65 y, 65 y+).