Is healthy behavior contagious: associations of social norms with physical activity and healthy eating

Background

Social norms are theoretically hypothesized to influence health-related behaviors such as physical activity and eating behaviors. However, empirical evidence relating social norms to these behaviors, independently of other more commonly-investigated social constructs such as social support, is scarce and findings equivocal, perhaps due to limitations in the ways in which social norms have been conceptualized and assessed. This study investigated associations between clearly-defined social norms and a range of physical activity and eating behaviors amongst women, adjusting for the effects of social support.

Methods

Self-report survey data about particular physical activity (leisure-time moderate-vigorous activity; volitional walking; cycling for transport) and eating behaviors (fast food, soft drink and fruit and vegetable consumption), and social norms and support for these, were provided by 3,610 women aged 18-46 years living in socioeconomically disadvantaged neighborhoods in Victoria, Australia.

Results

Results of regression analyses showed that social norms for physical activity and eating behaviors predicted these respective behaviors relatively consistently; these associations generally remained significant after adjustment for social support.

Conclusions

Acknowledging the cross-sectional study design, these data confirm theoretical accounts of the importance of social norms for physical activity and eating behaviors, and suggest that this is independent from social support. Intervention strategies aimed at promoting physical activity and healthy eating could incorporate strategies aimed at modifying social norms relating to these behaviors.

Influence of peers on breastfeeding discontinuation among new parents: the Melbourne InFANT Program

OBJECTIVE

We aimed to investigate whether the proportion of breastfeeding mothers in first-time parent groups influenced the likelihood of ceasing breastfeeding and whether this was independent of socioeconomic position.

METHODS

Data were from 501 mothers (from 62 first-time parent groups initiated approximately 6 weeks after birth) who provided data at the baseline and mid-intervention assessments of the Melbourne Infant Feeding, Activity, and Nutrition Trial. Parent groups were divided into those in which <or=25% of mothers had ceased breastfeeding by 6 weeks (low-cessation groups) and those in which >25% had ceased by 6 weeks (high-cessation groups).

RESULTS

With the exclusion of mothers who had already ceased breastfeeding by 6 weeks, the proportion of mothers who ceased breastfeeding between the time of parent group initiation (6 weeks) and 6 months was higher in high-cessation groups than in low-cessation groups (37.4% vs 21.7%; P=.001). After adjustment for maternal age, BMI, employment, and education and area-level socioeconomic position, membership in a group in which a large proportion of mothers had ceased breastfeeding by 6 weeks was strongly related to cessation of breastfeeding before 6 months (odds ratio: 2.1 [95% confidence interval: 1.3-3.3]).

CONCLUSIONS

Attendance at parent groups where peers are breastfeeding infants of a similar age may have an important influence on the continuation of breastfeeding to 6 months. First-time parent groups or other similar groups may be an important setting in which to promote the continuation of breastfeeding.

Why do some socioeconomically disadvantaged women eat better than others? An investigation of the personal, social and environmental correlates of fruit and vegetable consumption

The purpose of this paper was to examine the contribution of individual, social and environmental factors to predicting fruit and vegetable consumption among women of low socioeconomic position (SEP). An Australian community sample of 355 women of low SEP provided survey data on sociodemographic information, diet (fruit and vegetable consumption), and various cognitive, behavioural, social and perceived environmental influences on healthy eating. Information on the availability and accessibility of major chain supermarkets and fruit and vegetable stores from participant's residence was collected through objective audits. Women who were older, dieting to lose weight, had a greater taste preference for fruit and perceived the cost of fruit to be lower were more likely to be high fruit consumers. Women who had a high BMI were more likely to be high vegetable consumers. Women who perceived a greater availability of healthy foods in their neighbourhoods were more likely to be high fruit and vegetable consumers. Strategies aimed at increasing fruit and vegetable consumption among low SEP women should focus on modifying perceptions about the cost, availability and taste of fruits and vegetables. Tailoring nutrition interventions to accommodate differences in age, weight-control practices and weight status may also prove beneficial.

Physical activity, sedentary behavior and depression among disadvantaged women

This study investigated associations between components of physical activity (PA; e.g. domain and social context) and sedentary behaviors (SBs) and risk of depression in women from disadvantaged neighborhoods. A total of 3645 women, aged 18-45 years, from disadvantaged neighborhoods, self-reported their PA, SB and depressive symptoms. Crude and adjusted odds ratios and 95% confidence intervals were calculated for each component of PA, SB and risk of depression using logistic regression analyses, adjusting for clustering by women's neighborhood of residence. Being in a higher tertile of leisure-time PA and transport-related PA was associated with lower risk of depression. No associations were apparent for domestic or work-related PA. Women who undertook a small proportion of their leisure-time PA with someone were less likely to be at risk of depression than those who undertook all leisure-time PA on their own. Women reporting greater time sitting at the computer, screen time and overall sitting time had higher odds of risk of depression compared with those reporting low levels. The domain and social context of PA may be important components in reducing the risk of depression. Reducing time spent in SB may be a key strategy in the promotion of better mental health in women from disadvantaged neighborhoods.

A low intensity, community based lifestyle programme to prevent weight gain in women with young children: cluster randomised controlled trial

OBJECTIVE

To develop and evaluate the effectiveness of a community behavioural intervention to prevent weight gain and improve health related behaviours in women with young children.

DESIGN

Cluster randomised controlled trial.

SETTING

A community setting in urban Australia.

PARTICIPANTS

250 adult women with a mean age of 40.39 years (SD 4.77, range 25-51) and a mean body mass index of 27.82 kg/m(2) (SD 5.42, range 18-47) were recruited as clusters through 12 primary (elementary) schools.

INTERVENTION

Schools were randomly assigned to the intervention or the control. Mothers whose schools fell in the intervention group (n=127) attended four interactive group sessions that involved simple health messages, behaviour change strategies, and group discussion, and received monthly support using mobile telephone text messages for 12 months. The control group (n=123) attended one non-interactive information session based on population dietary and physical activity guidelines.

MAIN OUTCOME MEASURES

The main outcome measures were weight change and difference in weight change between the intervention group and the control group at 12 months. Secondary outcomes were changes in serum concentrations of fasting lipids and glucose, and changes in dietary behaviours, physical activity, and self management behaviours.

RESULTS

All analyses were adjusted for baseline values and the possible clustering effect. Women in the control group gained weight over the 12 month study period (0.83 kg, 95% confidence interval (CI) 0.12 to 1.54), whereas those in the intervention group lost weight (-0.20 kg, -0.90 to 0.49). The difference in weight change between the intervention group and the control group at 12 months was -1.13 kg (-2.03 to -0.24 kg; P<0.05) on the basis of observed values and -1.11 kg (-2.17 to -0.04) after multiple imputation to account for possible bias created by missing values. Secondary analyses after multiple imputation showed a difference in the intervention group compared with the control group for total cholesterol concentration (-0.35 mmol/l, -0.70 to -0.001), self management behaviours (diet score 0.18, 0.13 to 0.33; physical activity score 0.24, 0.05 to 0.43), and confidence to control weight (0.40, 0.11 to 0.69). Regular self weighing was associated with weight loss in the intervention group only (-1.98 kg, -3.75 to -0.23).

CONCLUSIONS

Weight gain in women with young children could be prevented using a low intensity self management intervention delivered in a community setting. Self management of health behaviours improved with the intervention. The response rate of 12%, although comparable with that in other community studies, might limit the ability to generalise to other populations.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry number ACTRN12608000110381.

Urban-rural comparison of weight status among women and children living in socioeconomically disadvantaged neighbourhoods

OBJECTIVE

To compare the weight status of women and children living in socioeconomically disadvantaged rural and urban neighbourhoods in Victoria.

DESIGN, SETTING AND PARTICIPANTS

Cross-sectional study of data collected between August 2007 and July 2008 as part of the Resilience for Eating and Activity Despite Inequality (READI) study. Women aged 18-45 years living in 40 rural and 40 urban socioeconomically disadvantaged Victorian areas were surveyed by postal questionnaire. Data from a subset of their children aged 5-12 years were also analysed. Weight and height were self-reported for women and measured for children.

MAIN OUTCOME MEASURES

Women's weight status based on body mass index (BMI): underweight; healthy; overweight; or obese Class I, II or III; children's weight status based on International Obesity Taskforce BMI cut-off points.

RESULTS

Of 11 940 women randomly selected, 4934 (41%) replied to a postal invitation to participate. After exclusions for various reasons, data were available on 3879 women and 636 of their children. Twenty-four per cent of urban and 26% of rural women were classified as overweight; a further 19% of urban and 23% of rural women were classified as obese. Twenty per cent of both urban and rural children were classified as overweight; a further 10% of urban and rural children were classified as obese. In crude analyses, rural women had higher odds of Class I and II obesity (odds ratio [OR], 1.34 and 1.72, respectively) compared with urban women. After adjusting for sociodemographic factors (age, number of children, country of birth, education level, employment status and marital status), there was no difference between urban and rural women in odds of overweight or obesity Class I, II or III. No significant urban-rural difference in odds of overweight/obesity was evident among children.

CONCLUSIONS

The higher prevalence of obesity in rural women compared with urban women was largely explained by individual-level sociodemographic factors, such as age, number of children, country of birth, education level, employment status and marital status. This suggests that higher obesity levels among women in rural areas may be attributable to the sociodemographic composition of these areas.

Personal, social and environmental correlates of resilience to physical inactivity among women from socio-economically disadvantaged backgrounds

While sex and socio-economic disparities in physical activity have been well documented, not all disadvantaged women are inactive. This study aimed to examine correlates of achieving recommended levels of physical activity among women of low socio-economic position. In 2005, a population-based sample of 291 women with low educational attainment provided survey data on leisure time physical activity (LTPA). Participants reported potential personal (enjoyment and self-efficacy; barriers; intentions; guilt and priorities; routines and scheduling; occupational physical activity; television viewing), social (support from family/friends; social participation; sport/recreation club membership; dog ownership) and environmental (aesthetics; safety; local access; footpaths; interesting walks; busy roads to cross; heavy traffic) correlates of physical activity. Nearly 40% of participants achieved recommended LTPA (150 min week(-1)). Multivariable analyses revealed that higher levels of self-efficacy for walking [prevalence ratio (PR) 2.05, 95% confidence interval (CI) 1.19-3.53], higher enjoyment of walking (PR 1.48, 95% CI 1.04-2.12), greater intentions to be active (PR 1.97, 95% CI 1.12-3.45) and having set routines for physical activity (PR 1.91, 95% CI 1.18-3.09) were significantly associated with achieving recommended LTPA. Personal factors were the characteristics most strongly associated with achieving recommended levels of LTPA among women from socio-economically disadvantaged backgrounds.

Personal, social and environmental correlates of healthy weight status amongst mothers from socioeconomically disadvantaged neighborhoods: findings from the READI study

BACKGROUND

Socioeconomically disadvantaged mothers are at high risk of obesity, yet the aetiology of obesity in this group remains poorly understood. The aim of this study was to examine the perceived personal, social and physical environmental factors associated with resilience to obesity among mothers from socioeconomically disadvantaged neighbourhoods.

METHODS

Survey data were provided by a cohort of 1840 women aged 18-46 years with dependent children (aged 0-18 years) from 40 urban and 40 rural socioeconomically disadvantaged neighbourhoods across Victoria, Australia. Mothers responded to a number of questions relating to personal, social and environmental influences on their physical activity and eating habits. Mothers' weight status was classified as healthy weight (BMI: 18.5-24.99), overweight (BMI: 25-29.99) or obese (BMI: 30+).

RESULTS

Mothers' weight status was bivariably associated with factors from all three domains (personal, social and physical environmental). In a multivariable model, mothers' perceived ability to make time for healthy eating (OR = 1.34) and physical activity (OR = 1.11) despite family commitments, and the frequency with which families ate healthy low-fat foods with mothers (OR = 1.28) remained significantly positively associated with healthy weight status. The frequency with which families encouraged eating healthy low-fat foods remained negatively associated (OR = 0.81) with weight status; ie greater encouragement was associated with less healthy weight status.

CONCLUSIONS

Drawing on the characteristics of mothers resilient to obesity might assist in developing intervention strategies to help other mothers in socioeconomically disadvantaged neighbourhoods to manage their weight. Such strategies might focus on planning for and prioritising time for healthy eating and physical activity behaviours, and including family members in and encouraging family mealtimes.

Individual, social and environmental correlates of physical activity among women living in socioeconomically disadvantaged neighbourhoods

Women living in socioeconomically disadvantaged neighbourhoods are at heightened risk for physical inactivity, but little is known about the correlates of physical activity among this group. Using a social-ecological framework, this study aimed to determine the individual, social and neighbourhood environmental correlates of physical activity amongst women living in such neighbourhoods. During 2007-2008 women (n = 4108) aged 18-45 years randomly selected from urban and rural neighbourhoods of low socioeconomic status in Victoria, Australia completed the International Physical Activity Questionnaire (long). They reported on individual (self-efficacy, enjoyment, intentions, outcome expectancies, skills), social (childcare, social support from family and friends/colleagues, dog ownership) and neighbourhood environmental (neighbourhood cohesion, aesthetics, personal safety, 'walking environment') factors. Multinomial logistic regression was used to examine the odds of increasing categories of leisure time physical activity (LTPA) and transport-related physical activity (TRPA) for each individual, social and environmental factor. In partially adjusted analyses, all individual, social and environmental variables were positively associated with LTPA, while all individual factors, family and friend support and the walking environment were positively associated with TRPA. In fully adjusted multivariable models, all individual and social factors remained significantly associated with LTPA, while self-efficacy, enjoyment, intentions, social support, and neighbourhood 'walking environment' variables remained significantly associated with TRPA. In conclusion, individual and social factors were most important for LTPA, while individual, social and neighbourhood environmental factors were all associated with TRPA. Acknowledging the cross-sectional design, the findings highlight the importance of different levels of potential influence on physical activity in different domains, which should be considered when developing strategies to promote physical activity amongst women living in socioeconomically disadvantaged neighbourhoods.

Neighbourhood physical activity environments and adiposity in children and mothers: a three-year longitudinal study

BACKGROUND

Although neighbourhood environments are often blamed for contributing to rising levels of obesity, current evidence is based predominantly on cross-sectional samples. This study examined associations between objectively-measured environmental characteristics of neighbourhoods and adiposity cross-sectionally and longitudinally over three years in children and their female carers.

METHODS

Longitudinal study of 140 5-6 year-old and 269 10-12 year-old children and their female carers (n = 369). At baseline (2001) and follow-up (2004), height and weight were measured among children and self-reported among female carers, and were used to compute BMI z-scores and BMI, respectively. A Geographic Information System determined access to destinations (public open spaces, sports options, walking/cycling tracks), road connectivity (density of cul-de-sacs and intersections, proportion of 4-way intersections, length of 'access' paths (overpasses, access lanes, throughways between buildings)) and traffic exposure (length of 'busy' and 'local' roads) within 800 m and 2 km of home. Univariate and multivariable linear regression analyses examined associations between environmental characteristics and BMI/BMI z-scores at baseline and change in BMI/BMI z-scores over the three years.

RESULTS

Cross-sectionally, BMI z-score was inversely associated with length (km) of access paths within 800 m (b = -0.50) and 2 km (b = -0.16) among younger and number of sport/recreation public open spaces (b = -0.14) and length (km) of 'access' paths (b = -0.94) within 800 m and length of local roads within 2 km (b = -0.01) among older children. Among female carers, BMI was associated with length (km) of walking/cycling tracks (b = 0.17) and busy roads (b = -0.34) within 800 m. Longitudinally, the proportion of intersections that were 4-way (b = -0.01) within 800 m of home was negatively associated with change in BMI z-score among younger children, while length (km) of access paths (b = 0.18) within 800 m was significant among older children. Among female carers, options for aerobics/fitness and swimming within 2 km were associated with change in BMI (B = -0.42).

CONCLUSION

A small number of neighbourhood environment features were associated with adiposity outcomes. These differed by age group and neighbourhood scale (800 m and 2 km) and were inconsistent between cross-sectional and longitudinal findings. However, the results suggest that improvements to road connectivity and slowing traffic and provision of facilities for leisure activities popular among women may support obesity prevention efforts.

Individual, social and physical environmental correlates of children's active free-play: a cross-sectional study

BACKGROUND

Children's unstructured outdoor free-play (or active free-play) has the potential to make an important contribution to children's overall physical activity levels. Limited research has, however, examined physical activity in this domain. This study examined associations between individual, social and physical environmental factors and the frequency with which children play in particular outdoor locations outside school hours. This study also investigated whether the frequency of playing in outdoor locations was associated with children's overall physical activity levels.

METHODS

Participants including 8-9 year old children and their parents (n = 187) were recruited from a selection of primary schools of varying socioeconomic status across metropolitan Melbourne, Australia. Parents completed a survey and children's overall physical activity levels were measured by accelerometry. Regression models examined the odds of children playing in various outdoor settings according to particular correlates.

RESULTS

Inverse associations were found between preference for activities not involving physical activity, and the likelihood of children playing in the yard at home on the weekend (OR = 0.65; CI = 0.45,0.95). Positive correlates of children playing in their own street included: parental perceptions that it was safe for their child to play in their street (weekdays [OR = 6.46; CI = 2.84,14.71], weekend days [OR = 6.01; CI = 2.68,13.47]); children having many friends in their neighbourhood (OR = 2.63; CI = 1.21,5.76); and living in a cul-de-sac (weekdays [OR = 3.99; CI = 1.65,9.66], weekend days [OR = 3.49; CI = 1.49,8.16]). Positive correlates of more frequent play in the park/playground on weekdays included family going to the park together on a weekly basis on weekdays (OR = 6.8; CI = 3.4,13.6); and on weekend days (OR = 7.36; CI = 3.6,15.0). No differences in mean mins/day of moderate-vigorous physical activity were found between children in the highest and lowest tertiles for frequency of playing in particular outdoor locations.

CONCLUSION

The presence of friends, safety issues and aspects of the built environment were reported by parents to be associated with children's active free-play in outdoor locations. Future research needs to further examine associations with time spent in active free-play and objectively-measured overall physical activity levels. It is also important to investigate strategies for developing a supportive social and physical environment that provides opportunities for children to engage in active free-play.

Deleterious associations of sitting time and television viewing time with cardiometabolic risk biomarkers: Australian Diabetes, Obesity and Lifestyle (AusDiab) study 2004-2005

OBJECTIVE

We examined the associations of sitting time and television (TV) viewing time with continuously measured biomarkers of cardio-metabolic risk in Australian adults.

RESEARCH DESIGN AND METHODS

Waist circumference, BMI, resting blood pressure, triglycerides, HDL cholesterol, fasting and 2-h postload plasma glucose, and fasting insulin were measured in 2,761 women and 2,103 men aged > or =30 years (mean age 54 years) without clinically diagnosed diabetes from the 2004-2005 Australian Diabetes, Obesity and Lifestyle (AusDiab) study. Multivariate linear regression analyses examined associations of self-reported sitting time and TV viewing time (hours per day) with these biomarkers, adjusting for potential confounding variables.

RESULTS

For both women and men, sitting time was detrimentally associated with waist circumference, BMI, systolic blood pressure, fasting triglycerides, HDL cholesterol, 2-h postload plasma glucose, and fasting insulin (all P < 0.05), but not with fasting plasma glucose and diastolic blood pressure (men only). With the exception of HDL cholesterol and systolic blood pressure in women, the associations remained significant after further adjustment for waist circumference. TV viewing time was detrimentally associated with all metabolic measures in women and all except HDL cholesterol and blood pressure in men. Only fasting insulin and glucose (men only) remained deleteriously associated with TV viewing time after adjustment for waist circumference.

CONCLUSIONS

In women and men, sitting time and TV viewing time were deleteriously associated with cardio-metabolic risk biomarkers, with sitting time having more consistent associations in both sexes and being independent of central adiposity. Preventive initiatives aimed at reducing sitting time should focus on both nonleisure and leisure-time domains.

Physical activity correlates in young women with depressive symptoms: a qualitative study

Background

Young women are at high risk for developing depression and participation in physical activity may prevent or treat the disorder. However, the influences on physical activity behaviors of young women with depression are not well understood. The aim of this study was to gather in-depth information about the correlates of physical activity among young women with and without depressive symptoms.

Methods

A sample of 40 young women (aged 18-30 years), 20 with depressive symptoms (assessed using the CES-D 10) and 20 without depressive symptoms participated in one-on-one semi-structured interviews. A social-ecological framework was used, focusing on the individual, social and physical environmental influences on physical activity. Thematic analyses were performed on transcribed interview data.

Results

The results indicated several key themes that were unique to women with depressive symptoms. These women more often described negative physical activity experiences during their youth, more barriers to physical activity, participating in more spontaneous than planned activity, lower self-efficacy for physical activity and being influenced by their friends' and family's inactivity.

Conclusions

Interventions designed to promote physical activity in this important target group should consider strategies to reduce/overcome early life negative experiences, engage support from family and friends and plan for activity in advance.