Stages of change to increase fruit and vegetable intake and its relationships with fruit and vegetable intake and related psychosocial factors (original) (raw)
Related papers
2014
Background and Purpose: To evaluate the effectiveness of two subsequent intervention components (motivational and self-regulatory components), placed in different order, to promote fruit and vegetable (FV) intake. Methods: After baseline assessment, university students (N = 205, aged 18-26 years) were allocated to two groups. One group received a motivational intervention (outcome expectancies, risk perception, and task self-efficacy) followed by a self-regulatory intervention (planning and dietary selfefficacy) after 17 days. The second group received the same intervention conditions in the opposite order. Follow-up assessments were done after another 17 days. Results: Both intervention sequences yielded gains in terms of FV intake and self-efficacy. However, this gain was only due to the self-regulatory component whereas the motivational component did not contribute to the changes. Moreover, changes in intention and self-efficacy mediated between intervention sequence and follow-up behavior, suggesting that improving these proximal predictors of FV intake was responsible for the behavioral gains. Conclusions: Findings highlight the superiority of a self-regulatory intervention over a motivational intervention when it comes to dietary changes in this sample of young adults. Moreover, changes in dietary selfefficacy may drive nutritional changes.
Global Health Promotion, 2013
This study tested the effect of theory-based interventions designed to increase fruit and vegetable intake (FVI). Adults (n = 291) were randomized into four groups: implementation intentions (II) group; self-efficacy (SE) group; combination of implementation intentions and self-efficacy (II+SE) group; and a control group receiving written information on nutrition. They were reassessed at 1, 3, 6 and 12 month follow-up. This study found that short interventions such as SE and II+SE can achieve significant differences in FVI at six-month follow-up compared to the control group. However, this effect was not maintained at 12-month follow-up. Practitioners should add materials or follow up meetings to ensure maintenance of behavioral change. (Global Health Promotion, 2013; 20 Supp. 2: 83-87).
Health Education Research, 2006
Effects of interventions targeting self-efficacy alone or combined with action plans were examined in the context of fruit and vegetable consumption. E-mail messages were sent to a self-efficacy group, a combined self-efficacy and action planning group and a control group. At a 6-month follow-up, 200 adults reported their fruit and vegetable consumption, along with current levels of self-efficacy and planning. The two experimental groups gained equally from the interventions, as documented by changes in behavior. In both intervention groups, change in respective cognitions predicted change in fruit and vegetable consumption. Parsimonious interventions might contribute to health behavior change.
Psychology & Health, 2011
This study tested the effect of interventions designed for people who do not eat yet the recommended daily fruit and vegetable intake (FVI) but have a positive intention to do so. Adults (N = 163) aged 20–65 were randomised into four groups: implementation intentions (II group), self-efficacy (SE group), combination of II + SE group) and a control group receiving written information on nutrition. Study variables were measured at baseline, post-intervention and at 3-month follow-up. At follow-up, compared to the control group, FVI increased significantly in the II and II + SE groups (1.5 and 1.9 servings per day, respectively). Most psychosocial variables significantly increased compared to the control group, with the exception of SE for vegetable intake (VI). Moreover, at 3-month follow-up, change in FVI was mediated by changes in fruit intake (FI) intention and VI action planning. In conclusion, II interventions were efficient to increase FVI, with or without consideration for the development of SE. Thus, future studies should favour the adoption of this approach to bridge the intention–behaviour gap for FVI.
Appetite, 2012
Interventions to increase fruit and vegetable intake typically apply manipulations that do not distinguish fruits and vegetables as separate food groups. This study aimed to compare the efficacy of separate implementation intention instructions with a combined implementation intention instruction on separate indices of fruit and vegetable intake, and investigate the written content of implementation intentions for behavioural strategies focusing on the 'target' action of consumption or the 'preparatory' actions that enable consumption. Participants (N = 580) were randomised to one of three conditions (control; separate implementation intentions; combined implementation intention). The findings were: (a) the combined instruction was successful in increasing fruit intake but not vegetable intake, whereas the separate instructions generated a significant increase in both fruit intake and vegetable intake, and (b) 'target' strategies appear more beneficial for increasing fruit intake where as preparatory strategies show some promise for vegetable intake. The conceptual and practical implications of this work are discussed in relation to future research into increasing fruit and vegetable consumption.
A Systematic Review of Behavioral Interventions to Promote Intake of Fruit and Vegetables
Journal of the American Dietetic Association, 2011
This review concluded that behaviour-based interventions modestly increased the intake of fruit and vegetables across the target population in the USA, but increases were small compared with the recommended level of intake. These conclusions should be interpreted with caution because of uncertainty on study quality and limitations in the review methods. Authors' objectives To assess the effectiveness of behaviour-based interventions on the promotion of fruit and vegetable intake. Searching PubMed and PsycINFO were searched for English studies between 2005 and 2010. Search terms were reported. Reference lists of retrieved studies were screened and experts in the field were contacted for any additional relevant studies. Study selection Randomised controlled trials (RCTs with at least 30 participants) and studies of pre-post, single-group design (with at least 80 participants), that evaluated behaviour-based interventions to promote intake of fruit and vegetables in the USA, were eligible for inclusion. Studies were only included if they explicitly reported the behaviour theory or construct used for the behaviour-based interventions. Studies of individuals with a specific clinical diagnosis (such as cancer, hypertension, diabetes or obesity) were excluded. Eligible studies had to report the outcome of fruit and vegetable intake (servings per day). The included studies adopted a variety of behaviour theories and/or constructs applied in the interventions, such as Transtheoretical Model, social cognitive theory, behavioural construct of self-efficacy and health promotion model with tailored messages. Motivational interviewing and group/individual diet education appeared to have been the main elements of behaviour-based interventions. For controlled trials, the most common comparators were no intervention and standard programme without tailored education sessions. The dietary measurement instruments used to estimate fruit and vegetables intake also varied between studies. The most commonly used tools were food frequency questionnaires, National Cancer Institute fruit and vegetables screener and 24-hour dietary recalls. Most included studies recruited healthy adults or children; some studies recruited special populations (such as work-site-based, minority and lower-income populations). The authors did not state how many reviewers assessed studies for inclusion. Assessment of study quality The authors did not state that they assessed study quality. Data extraction Data were extracted on mean and standard deviation for daily number of serving before and after intervention where possible. The significance levels between group comparisons were also reported. Data extraction was performed in triplicate. Methods of synthesis The studies were combined in a narrative synthesis, stratified by age group and specific populations. An average value of the outcome across studies was calculated. Results of the review Thirty-four studies were included in the review. The total number of included participants was not reported. Where reported, the sample size of studies ranged from 38 to 48,835.
The Impact of Nutrition-Teaching Self-Efficacy on Daily Fruit and Vegetable Intake
2011
The Impact of Nutrition-Teaching Self-Efficacy on Daily Fruit and Vegetable Intake by Leslie E. Rawls Hoglund M.Ed., Liberty University, 2008 Graduate Certificate in Public Health, The George Washington University, 2003 BS, Liberty University, 2000 Dissertation Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Public Health
Journal of Behavioral Medicine, 2012
Fruit and vegetable consumption represents a nutritional goal to prevent obesity and chronic illness. To change dietary behaviors, people must be motivated to do so, and they must translate their motivation into actual behavior. The present experiment aims at the psychological mechanisms that support such changes, with a particular focus on dietary self-efficacy and planning skills. A randomized controlled trial compared a theory-based psychological intervention with a health education session in 114 participants. Dependent variables were fruit and vegetable consumption, intention to consume more fruit and vegetables, planning to consume more, and dietary selfefficacy, assessed before the intervention, 1 week afterwards, and at 6-week follow up. Significant group by time interactions for all four dependent variables documented superior treatment effects for the psychological intervention group, with substantially higher scores at posttest and follow-up for the experimental group, although all students benefited from participation. To identify the contribution of the main intervention ingredients (self-efficacy and planning), regression analyses yielded mediator effects for these two factors. A social-cognitive intervention to improve fruit and vegetable consumption was superior to a knowledge-based education session. Self-efficacy and planning seem to play a major role in the mechanisms that facilitate dietary changes.
Motivating 18- to 24-Year-Olds to Increase Their Fruit and Vegetable Consumption
Journal of the American Dietetic Association, 2006
Objective This study assessed the effectiveness of a 4-month intervention using stage-based newsletters, computer-based communication, and motivational interviewing to increase fruit and vegetable consumption by college students aged 18 to 24 years. Design Participants were stratified by stage of change for fruit and vegetable consumption and randomized to an intervention or control group. Participants completed the staging algorithm for fruit and vegetable intake, which included a one-item food frequency question, a 26-item food frequency questionnaire (FFQ), an 18-item decisional balance questionnaire, and a five-item self-efficacy questionnaire at baseline and completion of study. Subjects A convenience sample of 437 college students enrolled in a rural, land grant university was enrolled in the study. Only nondietetics majors between ages 18 to 24 years were included in the study. A total of 314 students finished the study for a completion rate of 72%. Intervention After baseline staging and randomization, the intervention group participants received four stage-based newsletters, one motivational interview, and an individually tailored e-mail follow-up over a 4-month period. Control group participants only received assessment at baseline and at completion. Main outcome measures Two fruit and vegetable instruments, a one-item food frequency question, and a 26-item FFQ measured daily consumption of fruits and vegetables at baseline and postintervention. Statistical analyses performed The SAS system for Windows, version 8 (1999, SAS Institute, Inc, Cary, NC), was used for analysis, including the following tests: PROC GLM, PROC FREQ, and PROC NPAR1WAY, Kruskal-Wallis, Fisher, Wilcoxon rank sum, and 2 . Results Fruit and vegetable consumption increased significantly more for the intervention group than the control group. Consumption increased in the intervention group by one serving a day for both instruments compared with 0.4 servings a day in the control group for a one-item instrument and no change in the control group for a 26-item FFQ. Conclusions. This intervention is an effective way to increase fruit and vegetable consumption by young adults.