Emily Brindal

Features Predicting Weight Loss in Overweight or Obese Participants in a Web-Based Intervention: Randomized Trial

Background Obesity remains a serious issue in many countries. Web-based programs offer good potential for delivery of weight loss programs. Yet, many Internet-delivered weight loss studies include support from medical or nutritional experts, and relatively little is known about purely web-based weight loss programs. Objective To determine whether supportive features and personalization in a 12-week web-based lifestyle intervention with no in-person professional contact affect retention and weight loss. Methods We assessed the effect of different features of a web-based weight loss intervention using a 12-week repeated-measures randomized parallel design. We developed 7 sites representing 3 functional groups. A national mass media promotion was used to attract overweight/obese Australian adults (based on body mass index [BMI] calculated from self-reported heights and weights). Eligible respondents (n = 8112) were randomly allocated to one of 3 functional groups: information-based (n = 183), supportive (n = 3994), or personalized-supportive (n = 3935). Both supportive sites included tools, such as a weight tracker, meal planner, and social networking platform. The personalized-supportive site included a meal planner that offered recommendations that were personalized using an algorithm based on a user’s preferences for certain foods. Dietary and activity information were constant across sites, based on an existing and tested 12-week weight loss program (the Total Wellbeing Diet). Before and/or after the intervention, participants completed demographic (including self-reported weight), behavioral, and evaluation questionnaires online. Usage of the website and features was objectively recorded. All screening and data collection procedures were performed online with no face-to-face contact. Results Across all 3 groups, attrition was high at around 40% in the first week and 20% of the remaining participants each week. Retention was higher for the supportive sites compared to the information-based site only at week 12 (P = .01). The average number of days that each site was used varied significantly (P = .02) and was higher for the supportive site at 5.96 (SD 11.36) and personalized-supportive site at 5.50 (SD 10.35), relative to the information-based site at 3.43 (SD 4.28). In total, 435 participants provided a valid final weight at the 12-week follow-up. Intention-to-treat analyses (using multiple imputations) revealed that there were no statistically significant differences in weight loss between sites (P = .42). On average, participants lost 2.76% (SE 0.32%) of their initial body weight, with 23.7% (SE 3.7%) losing 5% or more of their initial weight. Within supportive conditions, the level of use of the online weight tracker was predictive of weight loss (model estimate = 0.34, P < .001). Age (model estimate = 0.04, P < .001) and initial BMI (model estimate = -0.03, P < .002) were associated with frequency of use of the weight tracker. Conclusions Relative to a static control, inclusion of social networking features and personalized meal planning recommendations in a web-based weight loss program did not demonstrate additive effects for user weight loss or retention. These features did, however, increase the average number of days that a user engaged with the system. For users of the supportive websites, greater use of the weight tracker tool was associated with greater weight loss.

Personal and lifestyle characteristics predictive of the consumption of fast foods in Australia.

OBJECTIVE To identify key predictors of fast-food consumption from a range of demographic, attitudinal, personality and lifestyle variables. METHODS We analysed data from a nationwide survey (n = 20 527) conducted in Australia by Nielsen Media Research. Items assessing frequency of fast-food consumption at (1) eat in and (2) take away were regressed onto 12 demographic, seven media consumption, and 23 psychological and lifestyle variables, the latter derived from factor analysis of responses to 107 attitudinal and behavioural items. RESULTS Stepwise multiple regression analyses explained 29.6% of the variance for frequency of take-away and 9.6% of the variance for frequency of eat-in consumption of fast foods. Predictors of more frequent consumption of fast food at take away (and, to a lesser extent, eat in) included lower age - especially under 45 years, relative indifference to health consequences of behaviour, greater household income, more exposure to advertising, greater receptiveness to advertising, lesser allocation of time for eating, and greater allocation of time to home entertainment. There were no effects for occupational status or education level. CONCLUSIONS The effects for age suggest that fast-food take-away consumption is associated with a general cultural shift in eating practices; individual differences in attitudinal and lifestyle characteristics constitute additional, cumulative, predictive factors. The role of advertising and the reasons for the lesser explanatory value of the eat-in models are important targets for further research.

Combined Home and School Obesity Prevention Interventions for Children What Behavior Change Strategies and Intervention Characteristics Are Associated With Effectiveness

This review identifies studies describing interventions delivered across both the home and school/community setting, which target obesity and weight-related nutrition and physical activity behaviors in children. Fifteen studies, published between 1998 and 2010, were included and evaluated for effectiveness, study quality, nutrition/activity content, behavior change techniques, and theoretical basis, using validated assessment tools/taxonomies. Seven studies were rated as effective. Behavior change techniques used to engage families, and techniques associated with intervention effectiveness were coded. Effective studies used about 10 behavior change techniques, compared with 6.5 in ineffective studies. Effective interventions used techniques including providing general information on behavior–health links, prompting practice of behavior, and planning for social support/social changes. Different behavior change techniques were applied in the home and school setting. The findings of this review provide novel insights into the techniques associated with intervention effectiveness that can inform the development of public health obesity prevention strategies.

Improving children's dairy food and calcium intake: can intervention work? A systematic review of the literature

OBJECTIVE Strategies are needed to address the shortfall in childrens dairy food and Ca intakes. The present review identified interventions targeting an increase in childrens dairy food or Ca intakes, and determined characteristics associated with successful intervention. DESIGN A systematic literature search identified fourteen intervention studies, published in English, between 1990 and 2010. Studies were evaluated for study population, setting and mode of delivery, dietary targets and outcome measures, measures of intervention intensity, intervention description, the use of behaviour change techniques and intervention effectiveness. SETTING Interventions targeting an increase in dairy food or Ca intake. SUBJECTS Children aged 5-12 years. RESULTS Ten of the fourteen studies were considered to be effective. Studies focusing on encouraging intake of dairy foods or Ca alone were all effective, compared with 55 % of studies promoting dairy within the context of a healthy diet. Effective interventions tended to be higher in intensity, provide dairy foods and were delivered across a variety of settings to a range of primary targets. The number of behaviour change techniques used did not differentiate effective and ineffective interventions, but the use of taste exposure and prompting practice appeared to be important for effective intervention. CONCLUSIONS Interventions that target an increase in childrens dairy food or Ca intake could potentially increase childrens dairy food intake by about one serving daily. Research conducted outside the USA is needed. The review has identified some promising strategies likely to be part of effective interventions for improving dairy and Ca intakes in countries where childrens intake is insufficient.

Ingesting breakfast meals of different glycaemic load does not alter cognition and satiety in children

Background/Objectives:The effect of Glycaemic Index (GI) and Load (GL) of breakfasts on satiety and aspects of cognitive function in children is inconclusive. We aimed to assess if isocaloric breakfasts differing in GL (by replacing high-GI carbohydrate foods with dairy protein foods) acutely alter cognitive function and satiety in 10- to 12-year-old children.Subjects/Methods:A total of 39 children, aged 11.6±0.7 years with body mass index 18.9±3.0 kg/m2 (Mean±s.e.) participated in a randomised crossover trial of three isocaloric breakfasts (1.3 MJ): high GL (HGL: 7 g protein, 9 g fat, 50 g carbohydrate, GL 33); medium GL (MGL: 14 g protein, 9 g fat, 45 g carbohydrate, GL 24) and low GL (LGL: 18 g protein, 10 g fat, 38 g carbohydrate, GL 18). Blood glucose was recorded using a continuous glucose monitor. Subjective hunger and cognitive performance were measured before and hourly after consuming the test breakfast via a computer-delivered battery. Ad libitum intake at a buffet lunch meal was measured at 3 h at the end of testing.Results:Incremental area under the glucose curve (iAUC) was significantly different with HGL>MGL>LGL (P<0.001). Glucose concentrations fell below baseline after 83±6 min for HGL, 63±5 min (MGL) and 67±5 min (LGL)(P=0.009). Breakfast GL did not significantly alter changes in cognitive function or self-reported satiety throughout testing. Energy intake at lunch was not significantly different between treatments (HGL 2943±168 kJ; MGL 2949±166 kJ; LGL 2993±191 kJ).Conclusions:Reducing breakfast GL by replacing carbohydrate with protein does not alter satiety or cognition over 3 h in 10- to 12-year-old children.

Engaging Families in Lifestyle Changes Through Social Networking

Previous research has shown that providing family engagement and social support play important roles in weight management success, helping to achieve long-term lifestyle changes. Traditionally, the support provided by online health communities is primarily targeted at individuals and does not involve their families. SOFA (SOcial FAmilies), a novel approach for engaging, motivating, and persuading families to adopt a healthy lifestyle, is proposed. SOFA is an online social network for families coupled with a repository of health-related educational content. This article reports the results of a live user study aimed at investigating how user profile representation and system-assigned tasks influence users engagement with the system and change their attitude toward a healthy lifestyle. The results show that representing family members as individuals increases the number of active members per family as well as their retention, contribution to, and engagement with the network. The results also show that family-based social networks positively change the attitude of family members toward a healthy lifestyle.

The effect of beverages varying in glycaemic load on postprandial glucose responses, appetite and cognition in 10–12-year-old school children

Reducing glycaemic index (GI) and glycaemic load (GL) inconsistently improves aspects of cognitive function and appetite in children. Whether altering the GL by lowering carbohydrate relative to protein and fat has a role in these effects is unknown. Therefore, we assessed the differential effects of beverages varying in GL and dairy composition on appetite, energy intake and cognitive function in children. A total of forty children (10–12 years) completed a double-blind, randomised, crossover trial, receiving three isoenergetic drinks (approximately 1100 kJ): a glucose beverage (GI 100, GL 65), a full milk beverage (GI 27, GL 5) and a half milk/glucose beverage (GI 84, GL 35). For 3 h post-consumption, subjective appetite and cognitive performance (speed of processing, memory, attention and perceptual speed) were measured hourly. At completion, each child was provided a buffet-style lunch and energy intake was calculated. Blood glucose was objectively measured using the Continuous Glucose Monitoring System. Blood glucose AUC values were significantly different between the drinks (P,0·001), but did not sustain above the baseline for 3 h for any drink. Mixed modelling revealed no effect of beverage on subjective appetite or energy intake. Participant sex and drink GL significantly interacted for short-term memory (P,0·001). When girls consumed either milk-containing beverage, they recalled 0·7–0·8 more words compared with 0·5 less words after the glucose drink (P#0·014). Altering GL of drinks by reducing carbohydrate and increasing protein did not affect appetite or cognition in children. Girls may demonstrate improved short-term memory after consuming beverages with higher protein and lower GL.

Improving health information access through social networking

Sustaining user participation is a challenge for even the most popular web sites. In this work we report on an effort to increase exposure to, and interaction with, a repository of health based information by coupling the repository with a social networking application. We hypothesize that we can sustain user interaction with a repository and increase nutrition knowledge through content browsing by reporting on the browsing actions of other users in a Social Networking Systems activity feeds. We report on the findings of a live user study, which showed that coupling health content with a social networking system successfully increased content browsing and that highly engaged users are seen to have an altered attitude toward control over their health.

Eating in groups: Do multiple social influences affect intake in a fast-food restaurant?

This study investigated multiple social influences to determine whether they affect amount eaten at a fast-food environment. Using observational methods, data on meal duration, foods eaten and personal characteristics were collected for 157 McDonald’s patrons. Analysis of covariance revealed that female diners ate less kilojoules when eating in mixed- versus same-sex groups (adjusted difference = 967 kJ, p < .05), while male diners eating in mixed-sex company ate more in groups compared to pairs (adjusted difference = 1067 kJ, p = .019). Influences to increase and restrict the amount eaten can operate simultaneously in an eating environment with gender a critical factor for consideration.

Factors associated with persistent participation in an online diet intervention

In recent years, much work has been carried out in interface design and service quality in order to maximise user experience and sustain engagement. We are often unsure, however, what factors really influence user interactions with the technologies. Here we report on an ongoing examination of the relationships between user demographics, self reported attitudes, efficacy, and system feature, and participation on an online diet support site. Our findings indicate that not only the characteristics of the users themselves are associated with sustained engagement with a weight loss site, but also that usage of particular features on the site results in higher return rates. These findings support a push for designers to understand their users and features of their site, in order to maximise engagement with their target audiences.