JMIR Publications

ABSTRACT

Background:

Dietary intake assessment is an integral part of addressing sub-optimal dietary intakes. Existing food-based methods often used in personalised nutrition are time consuming and burdensome for users to report the individual foods consumed at each meal. However, ease of use is the most important feature for individuals choosing a nutrition or diet app. Intakes of whole meals can be reported in a way that is less burdensome than reporting individual foods. No study has developed a method of dietary intake assessment where individuals report their dietary intakes as whole meals rather than individual foods.

Objective:

To develop a novel meal-based method of dietary intake assessment and test its ability to estimate nutrient intakes compared to a web-based 24-hour recall (24HR).

Methods:

Participants completed a web-based generic meal-based recall. This involved, for each meal type (breakfast, light meal, main meal, snack, beverage), choosing, from a selection of meal images, the ones that most represented their intakes during the previous day. Meal images were based on generic meals from previous research that were representative of actual meal intakes in Ireland. Participants also completed a web-based 24HR. Both methods were completed on the same day, three hours apart. Participants were randomized as to which method they completed first. Two weeks after the first dietary assessments, participants repeated the process in the reverse order. Estimates of mean daily nutrient intakes and categorisation of individuals according to nutrient-based guidelines (e.g., low, adequate, high) were compared between the two methods.

Results:

161 participants completed the study. For the 26 nutrient variables compared, the median percentage difference between the two methods was 7.4% with P-values ranging from <0.001 to 0.965, and effect sizes for the differences were small for 21 variables, moderate for three variables, and large for two variables. Correlation coefficients were statistically significant (P <0.05) for 21 of the 26 variables. Statistically significant correlations ranged from 0.16 to 0.45 with a median correlation of 0.32. When participants were classified according to nutrient-based guidelines, the proportion of individuals who were classified into the same category ranged from 52.8% to 84.5%.

Conclusions:

A generic meal-based method of dietary intake assessment provides comparable estimates of nutrient intake to a web-based 24-hour recall, but with varying levels of agreement among nutrients. Further work is required to refine and improve the generic recall across a range of nutrients. Future work will examine the feasibility of incorporating image recognition of whole meals into the generic recall.