Innovative dietary intake measurement tools, such as web-based food records, are becoming increasingly available for self-monitoring. However, the accuracy of this method has not been well studied. This pilot study aimed to evaluate the accuracy of energy intake (EI) estimated by a web-based food record, by comparison with total energy expenditure (TEE) measured by doubly-labelled water (DLW) in overweight and obese women.Methods
Total energy expenditure (TEE) was assessed in weight stable (±1 kg) women (n = 9), with a mean (SD) age of 34.5 (11.3) years and body mass index of 29.2 (1.4) kg m–2 over 10 days using the DLW technique. All food and beverages were self-reported for 9-days using a web-based food record and mean daily EI calculated. Food record accuracy was assessed by calculating the absolute (EI − TEE) and percentage (EI/TEE × 100) differences between EI and TEE. Women were identified as under-reporters of EI based on the 95% confidence limits of the expected EI: TEE of 1.Results
The mean (SD) self-reported EI was 8351 (1225) kJ day−1 [1996 (293) kcal day−1] and TEE was 10 648 (1774) kJ day−1 [2545 (424) kcal day−1]. The mean (SD) absolute difference in self-reported EI and TEE was −2301 (1535) kJ day−1 [−550 (367) kcal day−1], representing a mean reporting accuracy of 79.6% (14.1%), with four participants under-reporting EI.Conclusions
This pilot study highlights the opportunity for the use of the Internet as a novel medium for recording and assessing dietary intake. Although further research is needed in more diverse population groups, the accuracy of web-based food records for assessing EI appears to be consistent with other published dietary intake methods.