The effects of a web-based computer-tailored diet and physical activity intervention based on self-determination theory and motivational interviewing: A randomized controlled trial

Rationale and design of a randomized placebo-controlled nutritional trial embracing a citizen science approach

Modulation of the gut microbiota through specific dietary interventions shows potential for maintenance and optimization of health. A dietary fiber diet and fermented foods diet appear to alter the gut microbiota, but evidence is limited. Therefore, we designed the Gut Health Enhancement by Eating Favorable Food study, a 21-week randomized controlled trial studying effects of dietary fibers and fermented foods on gut microbiota diversity and composition, while also stimulating dietary behavior changes through a citizen science (CS) approach. We hypothesized that a high-fermented food diet would increase microbial diversity, whereas a high-dietary fiber diet would stimulate the growth of specific fiber-degrading bacteria. The following elements of CS were adopted: education on the gut microbiota, tailored dietary intervention, remote data collection by participants, sharing of personal gut microbiota outcomes with participants, and vlogs by participants for dissemination of results. Here we describe the study protocol and report the flow of participants, baseline characteristics, and compliance rates. Completed in March 2024, the trial included 147 healthy adults randomized to a high-dietary fiber intervention, high-fermented food intervention, or control group. Each group received an additional study product after 2 weeks: dried chicory root, a fermented beverage, or maltodextrin (placebo). A 3-month follow-up assessed the participants' ability to sustain dietary changes. The recruitment of participants was successful, reflected by 1448 applications. The compliance with the dietary guidelines and study products was >90%. This study shows that including elements of CS in an randomized controlled trial is feasible and may help recruitment and compliance.

Effectiveness of behavioural interventions with motivational interviewing on physical activity outcomes in adults: systematic review and meta-analysis

OBJECTIVE

To evaluate the effectiveness of behavioural interventions that include motivational interviewing on physical activity outcomes in adults.

DESIGN

Systematic review and meta-analysis.

STUDY SELECTION

A search of seven databases for randomised controlled trials published from inception to 1 March 2023 comparing a behavioural intervention including motivational interviewing with a comparator without motivational interviewing on physical activity outcomes in adults. Outcomes of interest were differences in change in quantitative measures of total physical activity, moderate to vigorous physical activity (MVPA), and sedentary time.

DATA EXTRACTION AND SYNTHESIS

Two reviewers extracted data and assessed risk of bias. Population characteristics, intervention components, comparison groups, and outcomes of studies were summarised. For overall main effects, random effects meta-analyses were used to report standardised mean differences (SMDs) and 95% confidence intervals (CIs). Differential effects based on duration of follow-up, comparator type, intervention duration, and disease or health condition of participants were also examined.

RESULTS

129 papers reporting 97 randomised controlled trials totalling 27 811 participants and 105 comparisons were included. Interventions including motivational interviewing were superior to comparators for increases in total physical activity (SMD 0.45, 95% CI 0.33 to 0.65, equivalent to 1323 extra steps/day; low certainty evidence) and MVPA (0.45, 0.19 to 0.71, equivalent to 95 extra min/week; very low certainty evidence) and for reductions in sedentary time (-0.58, -1.03 to -0.14, equivalent to -51 min/day; very low certainty evidence). Evidence for a difference in any outcome compared with comparators of similar intensity was lacking. The magnitude of effect diminished over time, and evidence of an effect of motivational interviewing beyond one year was lacking. Most interventions involved patients with a specific health condition, and evidence of an effect of motivational interviewing to increase MVPA or decrease sedentary time was lacking in general population samples.

CONCLUSIONS

Certainty of the evidence using motivational interviewing as part of complex behavioural interventions for promoting total physical activity in adults was low, and for MVPA and sedentary time was very low. The totality of evidence suggests that although interventions with motivational interviewing increase physical activity and decrease sedentary behaviour, no difference was found in studies where the effect of motivational interviewing could be isolated. Effectiveness waned over time, with no evidence of a benefit of motivational interviewing to increase physical activity beyond one year.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020219881.

Health-promotion interventions targeting multiple behaviors: A meta-analytic review of general and behavior-specific processes of change

Although health-promotion interventions that recommend changes across multiple behavioral domains are a newer alternative to single-behavior interventions, their general efficacy and their mechanisms of change have not been fully ascertained. This comprehensive meta-analysis (6,878 effect sizes from 803 independent samples from 364 research reports, N = 186,729 participants) examined the association between the number of behavioral recommendations in multiple-behavior interventions and behavioral and clinical change across eight domains (i.e., diet, smoking, exercise, HIV [Human Immunodeficiency Virus] prevention, HIV testing, HIV treatment, alcohol use, and substance use). Results showed a positive, linear effect of the number of behavioral recommendations associated with behavioral and clinical change across all domains, although approximately 87% of the samples included between 0 and 4 behavioral recommendations. This linear relation was mediated by improvements in the psychological well-being of intervention recipients and, in several domains (i.e., HIV, alcohol use, and drug use), suggested behavioral cuing. However, changes in information, motivation, and behavioral skills did not mediate the impact of the number of recommendations on behavioral and clinical change. The implications of these findings for theory and future intervention design are discussed. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Recruitment strategies for reaching adults aged 50 years and older with low socioeconomic status for participation in online physical activity interventions

Background

Generally, the health condition of those with higher socioeconomic status (SES) is better compared to those with lower SES. The application of appropriate strategies to reach low SES populations with electronic health (eHealth) interventions is thus of major importance to reduce health inequalities. eHealth-studies providing detailed information on recruitment strategies are scarce, despite the fact that this information is crucial for comparable research and implementation.

Objective

To provide insight into the reach, sample characteristics and costs of three pre-planned strategies for recruiting adults aged 50 years and older with low SES for participation in an online physical activity intervention, as part of a field study.

Methods

Recruitment took place via (1) invitation letters via a municipality, (2) gyms and (3) social media advertisements, aiming to include 400 participants. Additional procedures were followed to reach specifically the low SES group. Response rates, sociodemographic characteristics and costs per strategy were assessed.

Results

The highest response was shown for the municipality approach (N = 281), followed by social media (N = 71) and gyms (N = 45). Ten participants were recruited via family/friends. The most low-educated participants were reached via the municipality (N = 128) followed by social media (N = 9), gyms (N = 8) and family/friends (N = 5). Recruitment costs were with €2,142.37 the highest for the municipality compared to €96.81 for social media and no costs for gyms.

Conclusions

Recruitment via invitation letters through a municipality has the highest potential for reaching low SES participants of the three applied strategies, although the higher recruitment costs need to be taken into account.

Motivational interviewing-an evidence-based, collaborative, goal-oriented communication approach in lifestyle medicine: A comprehensive review of the literature

The global threat of noncommunicable diseases (NCDs) is alarmingly increasing. The health and economic burden of improper lifestyle choices is immense. Reducing modifiable risk factors has been demonstrated to significantly prevent chronic diseases. At this crucial time, lifestyle medicine (LM) has been recognized as an evidence-based medical domain applicable to NCDs. Among the tools used in LM, motivational interviewing (MI) is a patient-centered, collaborative counseling approach. In this evidence-based review article, we discuss recent literature on the application of MI in the six LM pillars defined by the British Society of LM (BSLM): healthy eating, mental wellbeing, healthy relationships, physical activity, minimizing harmful substances, and sleep. MI helps strengthen patients' motivation to ameliorate behaviorally influenced health problems, improve treatment adherence, and optimize medical interventions. Technically correct, theoretically congruent, and psychometrically sound MI interventions yield satisfactory outcomes and help improve patient quality of life. Lifestyle change is often a gradual process involving multiple efforts and setbacks. MI is based on the idea that change is a process rather than an event. Extensive literature evidence supports the benefits of MI treatment, and interest in research on MI application is increasing across all BSLM pillars. MI helps people alter their thoughts and feelings about making changes by recognizing obstacles to change. Even interventions of short duration have been reported to yield better outcomes. Healthcare professionals must understand the relevance and importance of MI in clinical practice.

A Proof-of-Concept Pilot Test of a Behavioral Intervention to Improve Adherence to Dietary Recommendations for Cancer Prevention

OBJECTIVES

Prevention programs that can help adults improve the quality of their diets to reduce cancer risk are needed. This Phase IIa study prospectively tested a mHealth intervention designed to improve adherence to dietary quality guidelines for cancer prevention.

METHODS

All participants (N = 62) received nutrition education and a self-regulation skills curriculum, with a primary target of changing grocery shopping behavior. Using a randomized, factorial design, the study varied whether each of the following 4 components were added to the 20-week intervention: (1) location-triggered app messaging, delivered when individuals arrived at grocery stores, (2) reflections on benefits of change, delivered with extra coaching time and tailored app messages, (3) coach monitoring, in which food purchases were digitally monitored by a coach, and (4) involvement of a household member in the intervention.

RESULTS

Benchmarks were successfully met for recruitment, retention, and treatment acceptability. Across conditions, there were significant reductions in highly processed food intake (P < .001, η2 = .48), red and processed meat intake (P < .001, η2 = .20), and sugar-sweetened beverage intake (P = .008, η2 = .13) from pre-to post-treatment. Analyses examining whether each intervention component influenced change across time found that participants who received coach monitoring increased their intake of fruits, vegetables, and fiber, whereas those with no coach monitoring had less improvement (P = .01, η2 = .14). The improvement in red and processed meat was stronger among participants with household support ON, at a marginally significant level, than those with household support OFF (P = .056, η2 = .07).

CONCLUSION

This study showed feasibility, acceptability, and preliminary signals of efficacy of a remotely delivered intervention to facilitate adherence to dietary guidelines for cancer prevention and that coach monitoring and household support may be especially effective strategies. A fully powered clinical trial is warranted to test an optimized version of the intervention that includes nutrition education, self-regulation skills training, coach monitoring, and household member involvement.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04947150.