The effect of an app-based dietary education on dietary intake and cardiometabolic risk markers in people with type 2 diabetes: results from a randomized controlled trial.

Background: mHealth, i.e. mobile-health, strategies may be used as a complement to regular care to support healthy dietary habits in primary care patients. We evaluated the effect of a 12-week smartphone-based dietary education on overall diet quality (primary outcome), and dietary intake and cardiometabolic risk markers (secondary outcomes) in people with type 2 diabetes.

Methods: In this two-armed randomized clinical trial, people with type 2 diabetes were recruited within a primary care setting and randomized 1:1 to a smartphone-delivered dietary education for 12 weeks or a control group receiving regular care only. Dietary intake and cardiometabolic risk markers were measured at baseline and after 3 months. Diet was assessed using a 4-day dietary record and a food frequency questionnaire (FFQ). Overall diet quality was estimated with a Nordic Nutrition Recommendation (NNR) score and specific dietary intake was estimated for 13 food groups/nutrients. We used linear regression models to examine differences in change from baseline to the 3-month follow-up between the intervention and control group, adjusted for baseline values of each outcome variable.

Results: The study included 129 participants (67 in the intervention group and 62 controls), of whom 61% were men. At baseline, mean age was 63.0 years and mean body mass index was 29.8 kg/m². When analyzing dietary record data, we found no effect of the intervention on diet quality or intake, however, the control group had increased their score by 1.6 points (95%CI: -2.9, -0.26) compared to the intervention group. In the analyses of FFQ data, the intervention group had lowered their daily intake in grams of saturated (β = -4.1, 95%CI: -7.9, -0.2) and unsaturated (mono- and polyunsaturated) (β = -6.9, 95%CI: -13.5, -0.4) fat more than the control group. The intervention group also presented lower serum triglycerides levels than the controls (β = -0.33, 95%CI: -0.60, -0.05). No statistical differences were found in any other dietary variables or cardiometabolic risk markers.

Conclusion: While we found no effect on overall diet quality, our findings suggest that a smartphone-based dietary education might impact dietary fat intake and corresponding cardiometabolic risk markers in people with type 2 diabetes. Our results should be considered hypothesis-generating and need to be confirmed in future studies.

Trial registration: Registered at ClinicalTrials.gov ( NCT03784612 ). Registered 24 December 2018.