Introduction
Observational studies often use food frequency questionnaires (FFQs) to assess diet soft drink intake as an indicator of non-nutritive sweetener (NNS) consumption (Keller et al., 2020; Mullee et al., 2019). However, NNS products extend far beyond diet soft drinks. Therefore the aim of this study was to (1) compare the use of a FFQ as an assessment of NNS intake, in comparison to a four week food diary and 24 hour food recalls and (2) identify patterns of NNS consumption.
Methods
Healthy adult participants completed a FFQ and then used a smartphone app (Easy Diet Diary, Xyris Software) to complete an estimated food diary of all food and beverage intake over a four week period. During this period they also completed three 24 hour food recalls. All dietary assessment methods were used to calculate NNS exposure and were compared.
Results
12 participants were recruited and 8 completed the study. Participants weighted 71.29kg (±7.83 SD). The food diary identified a higher frequency of NNS compared to the FFQ in five participants. All 8 participants consumed NNS and food diaries were filled out on 92.86% of days. Ten of the 28 NNS products consumed across all participants were diet soft drinks. One participant consumed diet soft drink only and 3 participants consumed no diet soft drink.
Conclusion
As demonstrated by these participants, there are a variety of food and beverage products contributing to NNS intake. NNS research needs to look beyond exclusively identifying the amount of diet soft drink in an individual’s diet. A multiple-week food diary is able to identify a variety of NNS containing products, however, it is also a high respondent burden method for dietary intake assessment. There are aspects of FFQs which could be improved to more accurately determine NNS intake without a high respondent burden.