Personality Traits and Body Weight Measures: Concurrent and Across–Time Associations

Personality, eating behaviour, and body weight: results from the population study of women in Gothenburg 2016/17

AIMS

The aim was to investigate the cross-sectional associations between personality traits, psychogenic needs and eating behaviour, and to describe the extent to which personality influences the association between eating behaviour and weight status.

METHODS

In 2016/17, a population-based sample of 573 women in Gothenburg, Sweden aged either 38 or 50 participated in a health examination. They completed the Three-Factor Eating Questionnaire, measuring uncontrolled eating, emotional eating and cognitive restraint on a scale of zero to 100. Scores higher than 50 defined excessive eating behaviour. The Cesarec-Marke Personality Schedule was used to measure psychogenic needs, characterised by pursuits and objectives that define personality and influence actions. Extraversion and neuroticism were assessed using the Eysenck-Personality Inventory. Regression models for excessive eating behaviour and for logarithmic body mass index (BMI) as a function of standardised personality scores were adjusted for sociodemographic, lifestyle and health factors.

RESULTS

A higher need to defend one's status (DST) was positively associated with excessive uncontrolled eating, odds ratio (OR) = 1.44, 95% confidence interval = (1.11, 1.86) per standard deviation (SD) of DST. The need to defend one's status was more strongly associated with excessive emotional eating, OR = 1.61 (1.18, 2.20) than neuroticism, OR = 1.45 (1.06, 1.97), in a mutually adjusted model. Needs for achievement and autonomy were associated with excessive cognitive restraint, OR = 1.39 (1.09, 1.76) and 0.78 (0.62, 0.97), respectively. Excessive emotional eating was associated with 5.3 (1.1, 9.6) % higher values of BMI when adjusted for the need of DST, which was associated with -2.7 (-4.1, -1.3) % lower BMI per SD.

CONCLUSIONS

Psychogenic needs were more closely associated with eating behaviour than personality traits. A lower need to defend one's status and excessive emotional eating were independently associated with higher BMI, suggesting different pathways to obesity and treatment strategies.

Behavioral adjustment moderates the effect of neuroticism on brain volume relative to intracranial volume

OBJECTIVE

The present study examined whether the effect of neuroticism on brain structure is moderated by behavioral adjustment.

BACKGROUND

Neuroticism is widely thought to be harmful to health. However, recent work using proinflammatory biomarkers showed that this effect depends on behavioral adjustment, the willingness and ability to adjust and cope with environmental contingencies, such as different opinions of others or unpredictable life situations. Here, we sought to extend this observation to "brain health" by testing total brain volume (TBV).

METHOD

Using a community sample of 125 Americans, we examined structural magnetic resonance imaging of the brain and quantified TBV. We tested whether the effect of neuroticism on TBV was moderated by behavioral adjustment, net of intracranial volume, age, sex, educational achievement, and race.

RESULTS

Behavioral adjustment significantly moderated the effect of neuroticism on TBV, such that neuroticism was associated with lower TBV only when behavioral adjustment was low. There was no such effect when behavioral adjustment was high.

CONCLUSION

The present findings suggest that neuroticism is not debilitating to those who constructively cope with stress. Implications are further discussed.

Body mass predicts personality development across 18 years in middle to older adulthood

OBJECTIVE

Various personality traits have longitudinal relations with body mass index (BMI), a measure of body weight and a risk factor for numerous health concerns. We tested these associations' compatibility with causality in either direction.

METHOD

Using three waves of the Wisconsin Longitudinal Study (N = 12,235, Mage  = 53.33 at baseline), we tested how accurately the Five-Factor Model personality domains and their items could collectively predict BMI and change in it with elastic net models. With multilevel models, we tested (a) bidirectional and (b) within-person associations between BMI and personality traits.

RESULTS

The five domains were able to predict concurrent (r = 0.08), but not future BMI. Twenty-nine personality items predicted concurrent and future BMI at r = 0.21 and r = 0.16 to 0.25, respectively. Neither the domains nor items could collectively predict change in BMI. Similarly, no individual trait predicted change in BMI, but BMI predicted changes in Conscientiousness, Agreeableness, and several items (|b*| = 0.03 to 0.08). BMI had within-person correlations with these same traits; time-invariant third factors like genetics or childhood environments therefore could not (fully) account for their relations.

CONCLUSIONS

Body weight may contribute to adults' personality development, but the reverse appears less likely.

HEXACO personality factors as predictors of physical activity, resting heart rate, body mass index, and healthy lifestyle behaviors

BACKGROUND

Personality traits are known factors that may influence levels of physical activity and other healthy lifestyle measures and behaviors that ultimately lead to health problems later in life.

Participants And Procedure

The aim of this study was to examine the association between personality traits (HEXACO) and levels of physical activity and resting heart rate (RHR) - measured using Fitbits, BMI, and a self-reported whole-person healthy lifestyle score for N = 2580 college students. Data were collected and analyzed for students enrolled in a University Success type course from August 2017 to May 2021. The relationships between HEXACO personality traits and various physical activity and healthy lifestyle behaviors were analyzed by building several multiple regression models using R version 4.0.2.

Results

In general, students who are extraverted were more physically active and students who are more open to experience had a higher RHR, even when controlling for gender. Females and males however had different profiles as to how personality influenced physical activity and other health-related measures. Male extraverts with high negative emotionality scores tend to be more physically active, whereas females tend to be more physically active when they were high in extroversion and conscientiousness, and low in openness to experience. BMI values were higher for female participants with high honesty-humility and low agreeableness and conscientiousness scores. Females also had a lower RHR for high honesty-humility and emotionality and low conscientiousness scores.

CONCLUSIONS

Personality can influence levels of physical activity, RHR, and BMI. This is especially true of women. Being aware of one's personality and the relationship of personality traits to levels of physical activity and other measures of leading a healthy lifestyle can be beneficial in determining strategies to improve long-term health outcomes.

Influence of personality traits, gender, and socio-economic factors in obesity in the English Longitudinal Study of Ageing

Obesity is a chronic disorder associated with high mortality rates and high morbidity. The risk of obesity is associated with certain personality traits (PTs). Some studies have found correlations among some PTs and gender. Additionally, obesity implies higher costs in daily living. The aim of this paper is to overcome this problem in the literature and estimate the association between PTs and obesity by taking into account the economic situation of the individual. This study employs data from the English Longitudinal Study of Ageing (ELSA). We focus on waves 5 and 6 of the ELSA with a sample of 6562 individuals. The results suggests that the traits of agreeableness ( β = 0.071 , se = 0.016 , p < 0.001 $$ \beta =0.071, se=0.016,\kern0.5em p<0.001 $$ ) and openness ( β = 0.028 , se : 0.014 , p < 0.001 $$ \beta =0.028, se:0.014,\kern0.5em p<0.001 $$ ) are positively and significantly associated with obesity. On the other hand, consciousness has a negative and statistically significant effect on obesity β = 0.072 , se : 0.017 , p < 0.001 $$ \left(\beta =0.072, se:0.017,\kern0.5em p<0.001\right) $$ . Results are robust to the inclusion/exclusion of different regressors.

Type D Personality and Health Behaviors in People Living with Obesity

BACKGROUND

Considering that health behaviors and personality traits play an important role in the formation of health attitudes, the main objective of this study was to evaluate the relations that occur between type D personality and health behaviors in a group of obese patients.

METHODS

443 adult patients with BMI ≥ 30 kg/m2, who had been hospitalized in selected hospital facilities in the Silesian Voivodeship (Poland), participated in the study. Respondents completed three standardized questionnaires-the Multidimensional Health Locus of Control Scale, version A (MHLC-A), the Inventory of Health Behaviors (IZZ), and the Type D Scale (DS-14).

RESULTS

Patients with type D personality were characterized by the least effective mental attitudes and preventive behaviors, and differed significantly from the other personality types (intermediate and non-type D). Type D personality increased the risk of initiating improper health behaviors by more than five times. Regarding the sense of health control, patients with type D personality had significantly lower scores for the Internal Dimension subscale (21.3 ± 3.1) and higher for the Powerful Others Dimension subscale (24.0 ± 2.6), compared to patients with intermediate and non-type D personality. Proper health behaviors correlated with an internal sense of health control; the strongest correlation, defined as a medium, was with Preventive Behaviors (R = 0.42; p < 0.0001).

CONCLUSIONS

Type D personality was associated with poorer attitudes towards health. Among obese respondents with a type D personality, there was a significantly higher prevalence of those who believed that their health status was a consequence of chance events.

Association of Personality Traits with Life and Work of Medical Students: An Integrative Review

BACKGROUND

Personality traits are the basic components of an individual's personality. Although there are many published articles about the impact of personality traits on medical students, there is a lack of integrative reviews of existing articles. To close this gap, this review aims to summarize the impact of personality traits on medical students from two perspectives: life and work.

METHODS

The search was performed using the following databases: PubMed, Web of Science, Google Scholar, and EMBASE. All publications that assessed the impact of personality traits on life and work until February 2022 were selected.

RESULTS

Ninety-seven studies were included. The results suggest that personality traits could affect life performance, health outcomes, life satisfaction, the formation of doctor-patient relationships, mastery of knowledge, academic performance, and career planning. Different personality traits can have positive or negative impacts on these aspects.

CONCLUSIONS

The results of this review suggest that personality traits can affect medical students' lives and work. Therefore, based on the evaluation of the personality traits of medical students, it is necessary to design targeted courses and training for students to improve their personality traits, to bring about better results in their lives and work.

The relationship between Big Five Personality Traits, eating habits, physical activity, and obesity in Indonesia based on analysis of the 5th wave Indonesia Family Life Survey (2014)

This study investigated the association between Big Five Personality Traits (Openness to new experience, Conscientiousness, Extraversion, Agreeableness, Neuroticism) and nutrition-related variables (eating habits, physical activity, and obesity using Body Mass Index). We used secondary data from the Indonesia Family Life Survey (IFLS) wave 5 involving a total of 14,473 men and 16,467 women aged 15-101 years (mean = 37.34; SD = 14.916) in Indonesia that was selected by stratified random sampling conducted in the period 2014 to 2015. Data were collected through interviews with the Big Five Index 15 and a questionnaire similar to the Global Physical Activity Questionnaire which was translated into the Indonesian language, and based on measurements of height and weight. Analyses used binary logistic regression test controlled by socio-demographic factors (age, gender, education, occupation, and marital status) to determine the association between Big Five Personality Traits and eating habits (recommended and non-recommended foods), physical activity, and obesity. Results showed that openness and extraversion were positively associated with recommended and non-recommended foods, conscientiousness was positively associated with only recommended foods, agreeableness was positively associated with recommended foods, and negatively associated with only one non-recommended food. Whereas, neuroticism was positively associated with non-recommended foods and negatively associated with recommended foods. Openness (p = 0.010; OR = 1.015; 95% CI = 1.004-1.027) and conscientiousness (p < 0.001; OR = 1.045; 95% CI = 1.030-1.059) were associated with physical activity. Conscientiousness (p = 0.002; OR = 1.025; 95% CI = 1.009-1.041), extraversion (p < 0.001; OR = 1.079; 95% CI = 1.065-1.092), and neuroticism (p < 0.001; OR = 0.966; 95% CI = 0.953-0.978) were associated with obesity. Although some results were different from previous studies, these associations can be used as strategies of behavioral change due to the adaptation of personality characteristics, which can be modified even though the personality tends to be persistent. Further studies are needed to understand other mechanisms that might underlie this association.

Personality, weight loss and obesity-related well-being post-bariatric surgery

PURPOSE

The aim of the study was to examine the associations between personality, weight loss and obesity-related well-being post-bariatric surgery. It was hypothesised that persons who had undergone bariatric surgery who exhibit Extraversion, Conscientiousness, Agreeableness and Intellect/Imagination will have greater obesity-related well-being; whereas, those low on Emotional stability will have poorer obesity well-being.

METHOD

The cross-sectional sample comprised 127 females who had received bariatric surgery. The average age of participants was 45 years. Quality of life was measured using the Obesity-Related Well-Being scale (ORWELL 97). Personality was assessed with the International Personality Item Pool (IPIP) 50-item measure of the Five-Factor Model.

RESULTS

The mean BMI for the sample was 34.13 (SD = 7.8). Females with a larger BMI who had undergone bariatric surgery had lower obesity-related well-being. Conscientiousness was negatively associated with BMI. Separate Hierarchical regression analyses found that Emotional stability (Beta =  - .43,  - .47,  - .36) and Agreeableness (Beta = .27, .29, .25) predicted overall well-being, symptom occurrence and subjective relevance of distress, respectively. BMI predicted occurrence of symptoms (Beta = .23).

CONCLUSIONS

The findings have implications for the development of personality-informed interventions for bariatric patients in enhancing well-being and weight-loss maintenance following surgery.

LEVEL OF EVIDENCE

Level III: Evidence obtained from well-designed cohort or case-control analytic studies.

Two genetic analyses to elucidate causality between body mass index and personality

BACKGROUND/OBJECTIVES

Many personality traits correlate with BMI, but the existence and direction of causal links between them are unclear. If personality influences BMI, knowing this causal direction could inform weight management strategies. Knowing that BMI instead influences personality would contribute to a better understanding of the mechanisms of personality development and the possible psychological effects of weight change. We tested the existence and direction of causal links between BMI and personality.

SUBJECTS/METHODS

We employed two genetically informed methods. In Mendelian randomization, allele scores were calculated to summarize genetic propensity for the personality traits neuroticism, worry, and depressive affect and used to predict BMI in an independent sample (N = 3 541). Similarly, an allele score for BMI was used to predict eating-specific and domain-general phenotypic personality scores (PPSs; aggregate scores of personality traits weighted by BMI). In a direction of causation (DoC) analysis, twin data from five countries (N = 5424) were used to assess the fit of four alternative models: PPSs influencing BMI, BMI influencing PPSs, reciprocal causation, and no causation.

RESULTS

In Mendelian randomization, the allele score for BMI predicted domain-general (β = 0.05; 95% CI: 0.02, 0.08; P = 0.003) and eating-specific PPS (β = 0.06; 95% CI: 0.03, 0.09; P < 0.001). The allele score for worry also predicted BMI (β = -0.05; 95% CI: -0.08, -0.02; P < 0.001), while those for neuroticism and depressive affect did not (P ≥ 0.459). In DoC, BMI similarly predicted domain-general (β = 0.21; 95% CI:, 0.18, 0.24; P < 0.001) and eating-specific personality traits (β = 0.19; 95% CI:, 0.16, 0.22; P < 0.001), suggesting causality from BMI to personality traits. In exploratory analyses, links between BMI and domain-general personality traits appeared reciprocal for higher-weight individuals (BMI > ~25).

CONCLUSIONS

Although both genetic analyses suggested an influence of BMI on personality traits, it is not yet known if weight management interventions could influence personality. Personality traits may influence BMI in turn, but effects in this direction appeared weaker.

Personality and Body Mass Index in U.S. Military Veterans: Results from the National Health and Resilience in Veterans Study

The relationship between the "Big 5" personality dimensions and body mass index (BMI) were examined in a nationally representative sample (National Health and Resilience in Veterans Study) of male and female U.S. military veterans. Multivariable analyses were conducted to evaluate gender-specific associations between personality factors and BMI. Among male veterans, greater extraversion was associated with higher BMI, (β = 0.18), while lower conscientiousness (β = -0.18), agreeableness (β = -0.18), and emotional stability (β = -0.17) were associated with lower BMI. Among female veterans, only greater consciousness was associated with lower BMI. These associations were robust to effects of age, physical activity, depression, and posttraumatic stress disorder. The "Big 5" personality dimensions are differentially associated with BMI in male and female veterans. While conscientiousness was associated with lower BMI in both male and female veterans, three additional personality dimensions were linked to BMI in male veterans. Implications of these findings for obesity management are discussed.

Novelty seeking is associated with increased body weight and orbitofrontal grey matter volume reduction

Novelty seeking (NS) has previously been identified as a personality trait that is associated with elevated body mass index (BMI) and obesity. Of note, both obesity and reduced impulse control - a core feature of NS - have previously been associated with grey matter volume (GMV) reductions in the orbitofrontal cortex (OFC). Yet, it remains unknown, if body weight-related grey matter decline in the OFC might be explained by higher levels of NS. To address this question, we studied associations between NS, BMI and brain structure in 355 healthy subjects. Brain images were pre-processed using voxel-based morphometry (VBM). BMI was calculated from self-reported height and weight. The Tridimensional Personality Questionnaire (TPQ) was used to assess NS. NS and BMI were associated positively (r = .137, p = .01) with NS being a significant predictor of BMI (B = 0.172; SE B = 0.05; ß = 0.184; p = 0.001). Significant associations between BMI and GMV specifically in the OFC (x = -44, y = 56, z = -2, t(350) = 4.34, k = 5, p_FWE = 0.011) did not uphold when correcting for NS in the model. In turn, a significant negative association between NS and OFC GMV was found independent of BMI (x = -2, y = 48, z = -10, t(349) = 4.42, k = 88, p_FWE = 0.008). Body mass-related grey matter decrease outside the OFC could not be attributed to NS. Our results suggest that body-weight-related orbitofrontal grey matter reduction can at least partly be linked to higher levels of NS. Given the pivotal role of the OFC in overweight as well as cognitive domains such as impulse inhibition, executive control and reward processing, its association with NS seems to provide a tenable neurobiological correlate for future research.

Psychological Determinants of Continued Obesity One-Year Postbariatric Surgery

OBJECTIVE

Bariatric surgery is an effective treatment for obesity; however, an estimated 20% of patients do not experience significant weight loss postsurgery. This study examined the interaction of potential psychological factors and their mediating effects on the emotional eating of individuals one-year postbariatric surgery.

METHOD

Three-hundred and sixty-six obese individuals (348 females; 95.1%) with a body mass index greater than 30 kg/m² (M = 39.14; SD = 7.67) completed the Patient Health Questionnaire, the Brief Cope, the Big-Five Mini-Marker of Personality, and the Three-Factor Eating Questionnaire R-18.

RESULTS

The variance accounted for in emotional eating by age and 12 psychological factors were assessed via a four-step hierarchical multiple regression. Avoidant coping and the personality traits of extraversion, agreeableness, and in contrast to that hypothesized, emotional stability were significant predictors of emotional eating. Avoidant coping partially mediated the relationships of extraversion and emotional stability with emotional eating and fully mediated the relationship of agreeableness.

CONCLUSION

Certain personality traits may influence the preferred coping style chosen by individuals who experience continued obesity after bariatric surgery. Additional supports and tailored interventions that are matched with the needs of this population may subsequently be necessary to overcome emotional eating and improve weight loss.

Personality traits, dieting self-efficacy and health behaviors in emerging adult women: implications for health promotion and education

Background: The purpose of this study was to explore the associations between personality traits and dieting self-efficacy as well as health behaviors among emerging adult women. Methods: In this cross-sectional study, the sample consisted of 161 participants in age from 19 to 25 years, who were administered the NEO-Five-Factor Inventory, the Health BehaviorsInventory (HBI), and the Dieting Self-Efficacy Scale (DIET-SE). Results: Our findings indicated that personality traits explained both health behaviors and dieting self-efficacy (F = 6.21, df = 5,155, P<0.001, F = 6.42, df = 5,155, P<0.001, respectively).Neuroticism (B = -0.45, P<0.01) and agreeableness (B = 0.39, P<0.01) were investigated as significant predictors of females' health behaviors, whereas extraversion (B = -0.40, P<0.001),agreeableness (B = 0.20, P<0.05), and conscientiousness (B = 0.33, P<0.01) were related to dieting self-efficacy. In addition, the results suggested the mediational effect of dieting self efficacy in the relationship between personality traits (i.e., consciousness and agreeableness)and general health behaviors. Conclusion: The role of personality traits for dieting self-efficacy as well as physical health among emerging adult women was confirmed. As dieting self-efficacy turned out to be a mediation factor, the findings may be used in psychoeducation for patients.

Change in weight and personality in middle-aged and older adults

Objective: Personality is associated with weight change and the development of obesity across adulthood. The present study examines whether significant weight change, including weight loss and weight gain, is related to personality change in a large longitudinal sample of middle-aged and older adults.Design: Participants were adults aged 50-92 years (N > 5000; 59% women, Mean age = 65.51, SD = 8.20) drawn from the Health and Retirement Study (HRS). Personality, demographic, health and staff assessed weight and height were obtained at baseline and 8 years later.Main Outcome Measures: Personality traits.Results: Both weight loss and weight gain greater than 10% of baseline weight were related to a steeper decline in extraversion, openness and conscientiousness. Weight loss was further associated with the maintenance of neuroticism and to a steeper decline in agreeableness. This overall pattern of personality change was also associated with both unhealthy and healthy weight change. The associations were not moderated by BMI and generally remained significant after accounting for disease burden.Conclusion: The present study provides new evidence that both weight loss and weight gain are related to change in personality.

Parent-Reported Personality and Weight Transitions across Adolescence

Background: Adolescence is a critical transition point for body weight. Personality traits are associated consistently with weight and obesity risk in adulthood. We examined whether personality, particularly Conscientiousness (the tendency to be organized, disciplined, and responsible), is associated with weight outcomes between ages 13 and 17. Methods: Data are drawn from the Growing Up in Ireland suites of studies. Parents rated their child's personality at age 13, and trained staff measured weight and height at ages 13 and 17 (N = 4962). Logistic regression was used to predict risk of incident obesity and obesity remission between ages 13 and 17. Results: Among children who were not in the obesity category at age 13, higher Conscientiousness was associated with lower risk of moving into the obesity category by age 17, and, among children with obesity at age 13, Conscientiousness was associated with greater likelihood of moving to the nonobesity category by age 17. These associations were independent of sociodemographic characteristics, parent body mass index, and were similar across gender. The other five-factor model personality traits were unrelated to weight outcomes. Conclusions: Conscientiousness is one trait psychological factor implicated in weight transitions across a critical period during adolescence.

Personality Traits and Obesity

Objective: Previous studies investigating the association between body weight and personality traits have found mixed results. This paper uses a large data set and two different study designs (cross-sectional and longitudinal) to provide more consistent estimates of the effect of personality traits on obesity. Methods: The present study is based on data from the German Socio-Economic Panel (GSOEP) from the waves 2005 to 2013; GSOEP is a longitudinal survey of private households in Germany that has been carried out since 1984. Responses provided data about personality, measured using the BFI-S Questionnaire, data for self-rated body mass index BMI (to determine the obesity level), as well as information for potential confounders. Cross-sectional and longitudinal logistic regression models were used. Results: The cross-sectional study yielded statistically significant results for the association between the outcome variable and four personality factors neuroticism, extraversion, openness and agreeableness. After controlling for several potential confounders, the association between obesity and extraversion, openness as well as agreeableness remained; additionally, the personality factor consciousness reached statistical significance. In the longitudinal study, a statistically significant association was found only for two personality factors, namely extraversion and agreeableness. After adding the control variables, the FE-regression yielded an association only for agreeableness (negative). Gender differences were not significant. Discussion: The findings show that results of a cross-sectional study design differ from the outcome of the longitudinal study design. The latter stresses the association between excess weight and the personality factor agreeableness, contrasting with most outcomes of previous research.

Personality and the Social Experience of Body Weight

Personality traits have been associated consistently with objective and subjective experiences of body weight. We examine whether this association extends to social attitudes and behaviors related to weight. Participants were mothers with children (N=3,099) who completed measures of personality and weight-related attitudes and social interactions. Higher Neuroticism and higher Extraversion were associated with more negative attitudes towards persons with obesity and engagement in fat talk with their friends and around their children. Higher Conscientiousness was associated with fewer negative attitudes and interactions but greater phobia towards obesity, whereas higher Openness and higher Agreeableness were generally associated with more positive attitudes and experiences. The associations for Conscientiousness, Openness, and Agreeableness held only for participants at relatively lower body mass index. Higher Neuroticism and lower Conscientiousness were further associated with the experience of weight discrimination. The present research indicates that in addition to measured weight and body image, personality traits are associated with the social experience of body weight.

Behavioral Adjustment Moderates the Link Between Neuroticism and Biological Health Risk: A U.S.-Japan Comparison Study

Neuroticism, a broad personality trait linked to negative emotions, is consistently linked to ill health when self-report is used to assess health. However, when health risk is assessed with biomarkers, the evidence is inconsistent. Here, we tested the hypothesis that the association between neuroticism and biological health risk is moderated by behavioral adjustment, a propensity to flexibly adjust behaviors to environmental contingencies. Using a U.S.-Japan cross-cultural survey, we found that neuroticism was linked to lower biological health risk for those who are high, but not low, in behavioral adjustment. Importantly, Japanese were higher in behavioral adjustment than European Americans, and as predicted by this cultural difference, neuroticism was linked to lower biological health risk for Japanese but not for European Americans. Finally, consistent with prior evidence, neuroticism was associated with worse self-reported health regardless of behavioral adjustment or culture. Discussion focused on the significance of identifying sociocultural correlates of biological health.

Personality and Body Weight: Mechanisms, Longitudinal Associations and Context

Models of personality and health have grown in complexity as more is discovered about how traits are related to health-related behaviors, morbidity, and mortality. The present article applies a model of personality and health that incorporates longitudinal relations, behavioral and physiological mechanisms, and context to the relation between Five-Factor Model personality traits and body mass index (BMI) and obesity (BMI≥30). Conscientiousness is associated consistently with lower body weight; the relation between the other traits and BMI is more complex. Conscientiousness is also associated with risk of obesity over time, and specific aspects of Conscientiousness and Neuroticism are associated with greater weight gain and are also sensitive to changes in weight over time. Behavioral (e.g., physical activity) and physiological (e.g., inflammation) factors explain part of the association between personality and BMI. Finally, the broader social environment shapes the expression of personality in relation to body weight. This review highlights replicable associations between personality and BMI and potential mechanisms of this association. Future research needs to better address how specific aspects of the social and family environment moderate the relation between personality and BMI and take a lifespan perspective to better incorporate how traits contribute to weight starting in childhood.

Modeling prior information of common genetic variants improves gene discovery for neuroticism

Neuroticism reflects emotional instability, and is related to various mental and physical health issues. However, the majority of genetic variants associated with neuroticism remain unclear. Inconsistent genetic variants identified by different genome-wide association studies (GWAS) may be attributable to low statistical power. We proposed a novel framework to improve the power for gene discovery by incorporating prior information of single nucleotide polymorphisms (SNPs) and combining two relevant existing tools, relative enrichment score (RES) and conditional false discovery rate (FDR). Here, SNP's conditional FDR was estimated given its RES based on SNP prior information including linkage disequilibrium (LD)-weighted genic annotation scores, total LD scores and heterozygosity. A known significant locus in chromosome 8p was excluded before estimating FDR due to long-range LD structure. Only one significant LD-independent SNP was detected by analyses of unconditional FDR and traditional GWAS in the discovery sample (N = 59 225), and notably four additional SNPs by conditional FDR. Three of the five SNPs, all identified by conditional FDR, were replicated (P < 0.05) in an independent sample (N = 170 911). These three SNPs are located in intronic regions of CADM2, LINGO2 and EP300 which have been reported to be associated with autism, Parkinson's disease and schizophrenia, respectively. Our approach using a combination of RES and conditional FDR improved power of traditional GWAS for gene discovery providing a useful framework for the analysis of GWAS summary statistics by utilizing SNP prior information, and helping to elucidate the links between neuroticism and complex diseases from a genetic perspective.

Temperament and body weight from ages 4 to 15 years

Background/Objectives

In adulthood, conscientiousness and neuroticism are correlates of body weight and weight gain. The present research examines whether the childhood antecedents of these traits, persistence and negative reactivity, respectively, are associated with weight gain across childhood. We likewise examine sociability as a predictor of childhood weight gain and whether these three traits are associated with weight concerns and weight management strategies in adolescence.

Subjects/Methods

Participants (N=4,153) were drawn from the Longitudinal Study of Australian Children, an ongoing, population-based study of child and family health and well-being. At the baseline assessment, caregivers reported on their child's temperament. At every assessment from ages 4-5 to 14-15, study children were weighed and measured by trained staff; there were up to six biennial assessments of body mass index (BMI) and waist circumference. At age 14-15, study children (n=2,975) also self-reported on their weight concerns and weight management strategies.

Results

Study children rated lower in persistence or higher in negative reactivity in early childhood gained more weight between the ages of 4 and 15. Sociability was associated with weight gain among girls but not among boys. Lower persistence and higher negative reactivity at age 4-5 were also associated with greater weight concerns, restrained eating, and use of unhealthy weight management strategies at ages 14-15.

Conclusions

Childhood traits related to conscientiousness and neuroticism are associated with objective weight gain across childhood and with concerns and strategies to manage weight in adolescence. These results are consistent with a lifespan perspective that indicates that trait psychological functioning contributes to health-related markers from childhood through old age.

Factors Influencing the Incidence of Obesity in Australia: A Generalized Ordered Probit Model

The increasing health costs of and the risks factors associated with obesity are well documented. From this perspective, it is important that the propensity of individuals towards obesity is analyzed. This paper uses longitudinal data from the Household Income and Labour Dynamics in Australia (HILDA) Survey for 2005 to 2010 to model those variables which condition the probability of being obese. The model estimated is a random effects generalized ordered probit, which exploits two sources of heterogeneity; the individual heterogeneity of panel data models and heterogeneity across body mass index (BMI) categories. The latter is associated with non-parallel thresholds in the generalized ordered model, where the thresholds are functions of the conditioning variables, which comprise economic, social, and demographic and lifestyle variables. To control for potential predisposition to obesity, personality traits augment the empirical model. The results support the view that the probability of obesity is significantly determined by the conditioning variables. Particularly, personality is found to be important and these outcomes reinforce other work examining personality and obesity.

Personality and Body-Mass-Index in School-Age Children: An Exploration of Mediating and Moderating Variables

This study explored longitudinal associations between personality and body-mass-index (BMI) in school-age children, including the potential mediating role of screen time and physical activity, and the potential moderating roles of child demographics and neighbourhood socioeconomic position. Participants were the parents (and teachers) of 3857 ten-year-old children, who completed questionnaires at baseline with a two-year follow-up. After controlling for child demographics (e.g., sex, pubertal status), we found that personality was unimportant for concurrent BMI, but was important for subsequent BMI and change in BMI over two years. Low levels of introversion and persistence at baseline, and decreases in persistence over time, were associated with a higher BMI at follow-up and a greater increase in BMI over time. Moderator analyses showed that introversion was more strongly related to subsequent BMI for children listed as aboriginal or Torres Strait Islander. The relationship between personality and change in BMI was mediated by screen time, but not by physical activity. To conclude, findings demonstrate that personality is important for change in body mass in Australian children (particularly indigenous children), and that screen-based sedentary behaviour features an important role in this association.

Are Trait–Outcome Associations Caused by Scales Or Particular Items? Example Analysis of Personality Facets and Bmi

In personality research, trait–outcome associations are often studied by correlating scale sum scores with an outcome. For example, an association between the NEO Impulsiveness scale and body mass index (BMI) is often interpreted to pertain to underlying trait Impulsiveness. We propose that this expectation can be corroborated by testing for Spearman's theorem of indifference of indicator. Namely, an underlying trait–outcome association should not depend on the specific items (i.e. indicators) used to measure the trait. To test this theorem, we outline an indicator exclusion procedure and demonstrate its viability using a simulation design. We then apply this procedure to test personality–BMI associations for indifference of indicator in a large population–based sample of adult Estonians (N = 2581) using self–ratings and informant ratings obtained with the NEO Personality Inventory–3. Our results show that the N5: Impulsiveness–BMI association mostly depends on two eating–related items, suggesting that the trait associated with BMI may be narrower than the trait the N5: Impulsiveness scale is supposed to measure. Associations between BMI, E3: Assertiveness and C2: Order seem to pertain to the trait. In sum, testing for indifference of indicator provides a potentially useful method to clarify trait–outcome relationships. R scripts are provided that implement the indicator exclusion procedure. Copyright © 2015 European Association of Personality Psychology

Personality Traits and Body Mass Index in Asian Populations

Research on personality and adiposity has focused primarily on Western samples; less is known about the personality correlates of BMI in Asian populations. We examined the association between personality and Body Mass Index (BMI) among community-dwelling Japanese adults (N=380), Chinese adolescents (N=5,882), and a meta-analysis inclusive of a published Korean sample (total N=10,304). In the new samples and meta-analysis, Extraversion and Agreeableness were associated with higher BMI among men. In contrast to what is often found in Western samples, Conscientiousness was mostly unrelated to adiposity. These findings link pro-social tendencies to overweight among Asian men; Conscientiousness may be less relevant for BMI in Eastern societies with a low prevalence of obesity and strong social norms for eating but not thinness.

Personality traits and body mass index: Modifiers and mechanisms

OBJECTIVE

To identify how demographic factors (sex, age, ethnicity) modify the association between personality traits and body mass index (BMI) and to test the extent that diet and physical activity account for the personality-BMI relations.

DESIGN

Cross-sectional study with a diverse sample (N = 5150, 50% female, 19% African American, 15% Hispanic). Participants completed a measure of the five major dimensions of personality and reported on their physical activity, diet and food intake behaviour, and height and weight.

MAIN OUTCOME MEASURES

BMI and obesity (BMI ≥ 30).

RESULTS

High Neuroticism was associated with higher BMI and risk for obesity, whereas Conscientiousness and, to a lesser extent, Extraversion and Openness were protective. These associations were generally stronger among women and older participants; there was less evidence for ethnicity as a moderator. Personality had similar relations with the behavioural factors, and physical activity, diet and regular meal rhythms accounted for approximately 50% of the association between Neuroticism and Conscientiousness and BMI.

CONCLUSION

This study supports the links between personality traits and BMI and suggests that physical activity, more than diet, is a key factor in these associations.

The association between personality traits and body mass index varies with nativity among individuals of Mexican origin

Personality traits have been associated consistently with health-related outcomes, but less is known about how aspects of the sociocultural environment modify these associations. This study uses a sample of participants of Mexican origin (N = 1013) to test whether exposure to the United States, indexed by nativity (Mexicans living in Mexico, foreign-born Mexican Americans, and U.S.-born Mexican Americans), moderates the association between personality traits and body mass index (BMI). Higher Conscientiousness was associated with lower BMI, regardless of nativity. In contrast, the association between Neuroticism and BMI was moderated by exposure to the U.S.: Neuroticism was associated with higher BMI among U.S.-born Mexican Americans (partial r = .15) but not among Mexican participants (partial r = .00), an effect strongest and most robust for the impulsivity facet of Neuroticism. This finding suggests that with more exposure to the United States, those who are more emotionally impulsive are at greater risk for obesity. More broadly, these findings suggest that social and psychological vulnerabilities interact to contribute to health outcomes.

Personality traits and obesity: a systematic review

Based on a bio-social-ecological systems model of the development and maintenance of obesity, there has been in the last few years a growing research interest in the association of obesity and personality traits. The aim of the present review was a comprehensive and critical evaluation of the existing literature taking into account the methodological quality of studies to enhance our understanding of personality traits associated with body weight, the development of overweight and obesity as well as the effectiveness of weight loss interventions including bariatric surgery. Personality traits play an important role both as risk as well as protective factors in the development of overweight and obesity. While thus in particular 'neuroticism', 'impulsivity' and 'sensitivity to reward' appear as risk factors, 'conscientiousness' and 'self-control' have been shown to have a protective function in relation to weight gain. Conscientiousness is a measure of regulation of internal urges and self-discipline, and may thus provide a potential source of control over impulsive reward-oriented behaviour. The results of the present review suggest that, within the context of therapeutic weight reduction measures, it is meaningful to identify subgroups of patients for whom specific treatment options need to be developed, such as measures for strengthening self-control skills.

Personality and Serum Lipids: Does Lifestyle Account for Their Concurrent and Long–Term Relationships

This study evaluates concurrent and over time associations of personality with measures of three serum lipids associated coronary heart disease morbidity, namely, high–density lipoprotein cholesterol (HDL–C), low–density lipoprotein cholesterol and triglyceride (TRI). Participants were individuals who underwent a health examination at two points of time, T1 (N = 3835) and T2 (N = 2283), about 2.5 years apart. Personality was assessed by the Five–Factor Model. Health, socioeconomic status and healthy lifestyle behaviours (smoking intensity, physical activity and body weight) were controlled. Regression analyses indicate that the personality factors of neuroticism, extraversion and conscientiousness are each significantly associated with HDL–C and TRI, both concurrently and over time. However, most of these associations decreased to marginal significance when adjusted for body weight or physical activity as possible mediators. Both concurrent and over time associations of the openness personality trait with HDL–C and TRI were significant and persisted after adjustment for measures of a healthy lifestyle. This study emphasizes the importance of collecting measures of a healthy lifestyle to better understand how personality might influence serum lipids. Copyright © 2013 European Association of Personality Psychology

Executive function and food approach behavior in middle childhood

Executive function (EF) has long been considered to be a unitary, domain-general cognitive ability. However, recent research suggests differentiating “hot” affective and “cool” cognitive aspects of EF. Yet, findings regarding this two-factor construct are still inconsistent. In particular, the development of this factor structure remains unclear and data on school-aged children is lacking. Furthermore, studies linking EF and overweight or obesity suggest that EF contributes to the regulation of eating behavior. So far, however, the links between EF and eating behavior have rarely been investigated in children and non-clinical populations. First, we examined whether EF can be divided into hot and cool factors or whether they actually correspond to a unitary construct in middle childhood. Second, we examined how hot and cool EF are associated with different eating styles that put children at risk of becoming overweight during development. Hot and cool EF were assessed experimentally in a non-clinical population of 1657 elementary-school children (aged 6–11 years). The “food approach” behavior was rated mainly via parent questionnaires. Findings indicate that hot EF is distinguishable from cool EF. However, only cool EF seems to represent a coherent functional entity, whereas hot EF does not seem to be a homogenous construct. This was true for a younger and an older subgroup of children. Furthermore, different EF components were correlated with eating styles, such as responsiveness to food, desire to drink, and restrained eating in girls but not in boys. This shows that lower levels of EF are not only seen in clinical populations of obese patients but are already associated with food approach styles in a normal population of elementary school-aged girls. Although the direction of effect still has to be clarified, results point to the possibility that EF constitutes a risk factor for eating styles contributing to the development of overweight in the long-term.