Summary: In a secondary analysis of a diabetes self-management app trial, users logging meals still averaged only 17.1 g/day of dietary fibre over a year, below the 20 g target, with no link between fibre intake and HbA1c or other characteristics, suggesting basic app feedback is not enough to raise fibre intake.
PICO Summary
| Element | Detail |
|---|---|
| Population | 47 of 66 intervention users with at least 7 days of complete meal records; secondary analysis of a 12-month RCT of the DialBetesPlus app, Japan. |
| Intervention | Use of the app’s dietary self-monitoring with basic nutritional feedback over 1 year. |
| Comparison | The recommended fibre intake of 20 g/day and above. |
| Outcome | Average fibre intake was 17.1 g/day (density 10.5 g/1000 kcal), with a rolling average consistently below 18 g and only a slight upward trend. Intake was highest at dinner. No significant correlation was found between fibre intake and age, sex, BMI, HbA1c, blood pressure, or logging frequency. |
Expert Commentary
This is a quietly valuable study precisely because it reports a shortfall rather than a success, and that honesty is its strength. The implicit hypothesis, that giving people a self-monitoring app with nutritional feedback would nudge fibre toward recommended levels, was not borne out: even engaged users who logged meals averaged about 17 g a day, stuck below 18 g across the year, and showed no relationship between fibre intake and HbA1c or any participant characteristic. The reasonable reading is that passive tracking and generic feedback are insufficient to change a stubborn dietary behaviour, which echoes the wider digital-health pattern where measurement alone rarely drives change. I would treat the absolute numbers cautiously, since they derive from app-based meal logging that can misestimate intake, and from a selected subset with adequate records, but the direction is informative. Can I use this with my patients? Yes, as a corrective expectation. It reminds me not to assume that recommending a tracking app will fix low fibre intake, and that achieving the fibre target usually needs more active strategies, concrete food swaps, dietitian input, or structured goals, rather than self-monitoring alone.
References
Sze WT, Waki K, Nakada R, Yamauchi T, Nangaku M, Ohe K. Dietary fiber estimate of DialBetesPlus app users: secondary analysis of data from a randomized controlled trial. JMIR Form Res. 2025;9:e69340. doi:10.2196/69340