2.3.2. Intake of Fruit and Vegetables

Data on the participants’ diets were registered via RiksmatenFlex, a web-based dietary assessment tool created by the Swedish Food Agency [21], using a repeated 24 h multiple pass recall. RiksmatenFlex is self-administrative and can be used on smartphones, tablets, and computers. In the RiksmatenFlex program, the participant enters the meals they have consumed and receives follow-up questions about the amount and specific food type. To help to determine serving sizes, pictures of different amounts of the dish in question were shown, and the participant chose the amount most similar to their portion size. This method gives detailed information about nutrient content and specific food groups in the registered diet and has been validated in this age group [20].

After an introduction to the program, the participants were able to register their diet themselves. The participants registered their diet for three whole days, i.e., the day that they visited the research center, the preceding day, and a randomly selected day after. Therefore, both the preceding day and the randomly selected day were registered retrospectively. The data from the day at the research center were excluded as the participants’ diets were provided for them for part of the day and therefore did not reflect a normal day. Therefore, the diet data were an average of the other two days. The participants registered the day that preceded the visit at the research center with guidance from the researchers and the last day they registered at home by themselves. The registration was checked for quality and completeness [21]. A total of 1036 participants had two days of dietary registrations, while 97 had one day and 6 participants had no completed registered days. Of those that had two complete days, 317 had two weekdays (Monday to Thursday), while the remaining participants had one weekday and one weekend day (Friday to Sunday).

The fruit and vegetable intake was based on the intake of vegetables, legumes, root vegetables, mushrooms, fruits, and berries in grams. Components of dishes, such as the tomatoes included in a lasagna were counted as well. The intake in grams was summed up and averaged over the two days. Additionally, energy intake in kilocalories (kcal) was calculated and averaged over the included days.

Participants were classified into under, plausible, or over-energy reporters using the ratio between energy intake (EI) and total energy expenditure (TEE). The calculations for TEE were done by using data on physical activity, weight (kg), and gender, as previously described [22]. Plausible reporters were categorized as those falling within one standard deviation (0.31) around the mean (0.82) of the ratio, while those that had a ratio of less than 0.51 were classified as under-reporters and those with a ratio of more than 1.13 were classified as over-reporters. Only those with two days of registered dietary intake were included in the calculations. A total of 1008 participants fulfilled the criteria. Of those, 690 (68.5%) were classified as plausible reporters.