Multiple behavior changes in diet and activity: a randomized controlled trial using mobile technology

Abstract

Background: Many patients exhibit multiple chronic disease risk behaviors. Research provides little information about advice that can maximize simultaneous health behavior changes.

Methods: To test which combination of diet and activity advice maximizes healthy change, we randomized 204 adults with elevated saturated fat and low fruit and vegetable intake, high sedentary leisure time, and low physical activity to 1 of 4 treatments: increase fruit/vegetable intake and physical activity, decrease fat and sedentary leisure, decrease fat and increase physical activity, and increase fruit/vegetable intake and decrease sedentary leisure. Treatments provided 3 weeks of remote coaching supported by mobile decision support technology and financial incentives. During treatment, incentives were contingent on using the mobile device to self-monitor and attain behavioral targets; during follow-up, incentives were contingent only on recording. The outcome was standardized, composite improvement on the 4 diet and activity behaviors at the end of treatment and at 5-month follow-up.

Results: Of the 204 individuals randomized, 200 (98.0%) completed follow-up. The increase fruits/vegetables and decrease sedentary leisure treatments improved more than the other 3 treatments (P < .001). Specifically, daily fruit/vegetable intake increased from 1.2 servings to 5.5 servings, sedentary leisure decreased from 219.2 minutes to 89.3 minutes, and saturated fat decreased from 12.0% to 9.5% of calories consumed. Differences between treatment groups were maintained through follow-up. Traditional dieting (decrease fat and increase physical activity) improved less than the other 3 treatments (P < .001).

Conclusions: Remote coaching supported by mobile technology and financial incentives holds promise to improve diet and activity. Targeting fruits/vegetables and sedentary leisure together maximizes overall adoption and maintenance of multiple healthy behavior changes.

Figures

Figure 1

Study Design & Participant Flow

Figure 2

Figure 2a: Standardized Composite Diet-Activity Improvement over Time for Each Treatment* *Abbreviations: FV↑ indicates increase fruit/vegetable; Fat↓ indicates decrease saturated fat; PA↑ indicates increase physical activity; Sed ↓ indicates decrease sedentary leisure. Gray background indicates treatment phase (weeks 0–3); white background indicates follow-up without treatment (weeks 4–20). Figure 2b: Mean (and SD¥) Standardized Composite Diet-Activity Improvement over Time for Increase Fruits/Vegetables, Decrease Sedentary Leisure versus All Other Treatments Combined* *Abbreviations: ¥SD indicates standard deviation. FV↑ indicates increase fruit/vegetable; Fat↓ indicates decrease saturated fat; PA↑ indicates increase physical activity; Sed↓ indicates decrease sedentary leisure. Gray background indicates treatment phase (weeks 0–3); white background indicates follow-up without treatment (weeks 4–20).

Figure 2

Figure 2a: Standardized Composite Diet-Activity Improvement over Time for Each Treatment* *Abbreviations: FV↑ indicates increase fruit/vegetable; Fat↓ indicates decrease saturated fat; PA↑ indicates increase physical activity; Sed ↓ indicates decrease sedentary leisure. Gray background indicates treatment phase (weeks 0–3); white background indicates follow-up without treatment (weeks 4–20). Figure 2b: Mean (and SD¥) Standardized Composite Diet-Activity Improvement over Time for Increase Fruits/Vegetables, Decrease Sedentary Leisure versus All Other Treatments Combined* *Abbreviations: ¥SD indicates standard deviation. FV↑ indicates increase fruit/vegetable; Fat↓ indicates decrease saturated fat; PA↑ indicates increase physical activity; Sed↓ indicates decrease sedentary leisure. Gray background indicates treatment phase (weeks 0–3); white background indicates follow-up without treatment (weeks 4–20).

Figure 3

Standardized Improvement in Each Behavior Produced by Increase Fruits/Vegetables, Decrease Sedentary Leisure Treatment* *Abbreviations: FV indicates fruits/vegetables; Fat indicates saturated fat; PA indicates physical activity; Sed indicates sedentary leisure. Gray background indicates treatment phase (weeks 0–3); white background indicates follow-up without treatment (weeks 4–20).

Figure 4

Effects of the 4 Treatments on Changes Over Time in Each Behavior Expressed in Natural Units* *Abbreviations: FV indicates fruits/vegetables; Fat indicates saturated fat; PA indicates physical activity; Sed indicates sedentary leisure. Gray background indicates treatment phase (weeks 0–3); white background indicates follow-up without treatment (weeks 4–20)