Familial resemblance in eating behaviors in men and women from the Quebec Family Study

Infancy and Childhood Obesity Grade Predicts Weight Loss in Adulthood: The ONTIME Study

We examined the relationships between intergenerational obesity, weight and size at birth, and obesity from infancy to adolescence with weight loss in response to a dietary intervention. We studied 4264 participants (3369 women; mean age 41.5 ± 12.9 years) of the ONTIME study. Participants followed a weight-loss treatment based on a Mediterranean diet. Associations between grandparental and parental obesity grade, birth weight and size, and obesity grade in infancy, childhood and adolescence with total weight loss in response to treatment were assessed, using multivariate linear regression models. A lower weight loss (kg) in response to treatment was found among participants who were obese during infancy (beta coefficient -2.13 kg; 95% CI, -3.96, -0.30; p = 0.023). Furthermore, obesity during infancy and also during childhood was associated with a slower weekly rate of weight loss during treatment (p < 0.05). In conclusion, obesity in infancy and in childhood impairs the weight-loss response to dietary treatments in adulthood. Tackling obesity throughout early life may improve the effectiveness of weight-loss interventions in adulthood.

Associations between partner's diet undermining and poor diet in mixed-weight, older gay married couples: a dyadic mediation model

BACKGROUND

Prior studies have examined how individuals may undermine their partner's efforts to maintain a healthy diet, but gay couples have not been represented in this work. Additionally, research has not accounted for mixed-weight status [lighter partner (LP) and heavier partner] nor investigated the mechanisms through which undermining is associated with dietary outcomes.

OBJECTIVE/DESIGN/MEASURES

Utilising dyadic data from 224 gay married couples across the United States, we tested associations between perceptions of partner's diet undermining strategies and diet quality with couple food disagreements and depressive symptoms as putative, serial mediators in an actor-partner interdependence mediation model.

RESULTS

Results revealed that more severe diet undermining was associated with both partners' poorer diet quality, which was explained by more frequent couple food disagreements and higher depressive symptoms for both heavier and LPs.

CONCLUSION

These findings suggest that undermining strategies are detrimental to both partners' relational health (increased conflict), emotional health (depressive symptoms) and physical health (diet)-regardless of weight status-and provide valuable targets for prevention and intervention. Our study underscores the interdependence of couple relations in lifestyle changes and specifically highlight the need for health professionals to discuss the partner's indirect or unintended disruptions to the patient's plan.

The role of eating behavior traits in mediating genetic susceptibility to obesity

Background

Genome-wide association studies (GWASs) have identified several genes associated with obesity. The mechanisms through which these genes affect body weight are not fully characterized. Recent studies suggest that eating behavior (EB) traits could be involved, but only a few EB traits were investigated.

Objective

This study aimed to investigate whether genetic susceptibility to obesity is mediated by EB traits (cognitive restraint, disinhibition, hunger) and their subscales. We hypothesized that EB traits, and their subscales, partly mediate this association.

Design

Adult individuals (n = 768) who participated in the Quebec Family Study were included in this cross-sectional study. A genetic risk score (GRS) of obesity was calculated based on the 97 genetic variants recently identified in a GWAS meta-analysis of body mass index (BMI). EB traits and their subscales were assessed with the use of the Three-Factor Eating Questionnaire. Regression analyses with age and sex as covariates were used to investigate the associations between GRS, EB traits, BMI, and WC and whether the association between GRS and obesity is mediated by EB traits, which represents the indirect effect of GRS on obesity.

Results

The GRS of obesity was positively associated with BMI (β = 0.19 ± 0.04, P < 0.0001) and WC (β = 0.46 ± 0.10, P < 0.0001). Regression analyses also revealed that the association between GRS of obesity and BMI was partly mediated by disinhibition and susceptibility to hunger (βindirect = 0.09 ± 0.03, P = 0.0007, and βindirect = 0.04 ± 0.02, P = 0.02, respectively). Habitual and situational susceptibility to disinhibition (βindirect = 0.08 ± 0.03, P = 0.002 and βindirect = 0.05 ± 0.02, P = 0.003, respectively) as well as internal and external locus of hunger (βindirect = 0.03 ± 0.02, P = 0.03 for both) were also found to mediate the association between GRS of obesity and BMI. The same trends were observed with WC.

Conclusions

The results of this study indicate that the genetic susceptibility to obesity is partly mediated through undesirable EB traits, which suggests that they could be targeted in obesity treatment and prevention. This trial was registered at clinicaltrials.gov as NCT03355729.

Eating Behavior, Stress, and Adiposity: Discordance Between Perception and Physiology

The purpose of the study was to examine the interrelationships among stress, eating behavior, and adiposity in a cohort of normal- and overweight individuals. Clinical markers of physiological stress (fasting serum cortisol) and adiposity (body mass index [BMI] and percent body fat) were obtained from participants selected for a natural history protocol ( n = 107). Self-reported data on eating behavior (using the Three-Factor Eating Questionnaire subscales such as Cognitive Restraint, Disinhibition, and Hunger) and psychological stress (via the Perceived Stress Scale) were evaluated. Demographic information was incorporated using principal component analysis, which revealed sex- and weight-based differences in stress, adiposity, and eating behavior measures. Following a cross-sectional and descriptive analysis, significant correlations were found between the Disinhibition and Hunger eating behavior subscales and measures of adiposity including BMI ( r = .30, p = .002 and r = .20, p = .036, respectively) and percent body fat ( r = .43, p = .000 and r = .22, p = .022, respectively). Relationships between stress measures and eating behavior were also evident in the analysis. Disinhibition and Hunger correlated positively with perceived stress ( r = .32, p .001 and r = .26, p = .008, respectively). However, Disinhibition varied inversely with serum cortisol levels ( r = -.25, p = .009). Future studies are warranted to better understand this paradox underlying the effects of perceived and physiological stress on eating behavior.

What Twin Studies Tell Us About Brain Responses to Food Cues

PURPOSE OF REVIEW

Functional magnetic resonance imaging (fMRI) using visual food cues provides insight into brain regulation of appetite in humans. This review sought evidence for genetic determinants of these responses.

RECENT FINDINGS

Echoing behavioral studies of food cue responsiveness, twin study approaches detect significant inherited influences on brain response to food cues. Both polygenic (whole genome) factors and polymorphisms in single genes appear to impact appetite regulation, particularly in brain regions related to satiety perception. Furthermore, genetic confounding might underlie findings linking obesity to stereotypical response patterns on fMRI, i.e., associations with obesity may actually reflect underlying inherited susceptibilities rather than acquired levels of adiposity. Insights from twin studies show that genes powerfully influence brain regulation of appetite, emphasizing the role of inherited susceptibility factors in obesity risk. Future research to delineate mechanisms of inherited obesity risk could lead to novel or more targeted interventional approaches.

Partner Influence in Diet and Exercise Behaviors: Testing Behavior Modeling, Social Control, and Normative Body Size

Previous research has documented social contagion in obesity and related health behaviors, but less is known about the social processes underlying these patterns. Focusing on married or cohabitating couples, we simultaneously explore three potential social mechanisms influencing obesity: normative body size, social control, and behavior modeling. We analyze the association between partner characteristics and the obesity-related health behaviors of focal respondents, comparing the effects of partners' body type, partners' attempts to manage respondents' eating behaviors, and partners' own health behaviors on respondents' health behaviors (physical activity, fruit and vegetable consumption, and fast food consumption). Data on 215 partners are extracted from a larger study of social mechanisms of obesity in family and community contexts conducted in 2011 in the United States. Negative binomial regression models indicate that partner behavior is significantly related to respondent behavior (p < .001), net of controls. These results are suggestive of a behavior modeling mechanism in obesity-related patterns of consumption and physical activity. In contrast, we find little support for the influence of normative body size or partner social control in this sample, though generalizations about the relevance of these processes may be inappropriate. These results underscore the importance of policies and interventions that target dyads and social groups, suggesting that adoption of exercise or diet modifications in one individual is likely to spread to others, creating a social environment characterized by mutual reinforcement of healthy behavior.

Parental control and overconsumption of snack foods in overweight and obese children

The associations between snack food consumption, parent feeding practices and general parenting in overweight in obese children are largely unknown. Therefore, we examined these relationships in 117 treatment-seeking overweight and obese children (10.40 ± 1.35 years; 53% female; 52% Caucasian; BMI-z: 2.06 ± .39). Children consumed a dinner meal, completed an Eating in the Absence of Hunger (EAH) free access paradigm (total EAH intake = EAH%-total; sweet food intake = EAH%-sweet), and completed the Child Report of Parent Behavior Inventory. Parents completed the Child Feeding Questionnaire. Child EAH%-total and EAH%-sweet were positively associated with dinner consumption (p's < .01). Girls had significantly higher EAH%-total compared to boys (p < .05). In separate models, higher EAH%-total was associated with greater use of maternal psychological control (p < .05) and EAH%-sweet was positively associated with parent monitoring (p < .05). In analyses examining factors associated with the consumption of specific foods, EAH snack food, parent restriction, pressure to eat, monitoring, and maternal psychological control were positively correlated with intake of Hershey's(®) chocolate bars (p's < .05). In summary, parental monitoring is associated with child sweet snack food intake and maternal psychological control is associated with child total snack food consumption. Future research should evaluate the complex relationship between child eating and parenting, especially with regard to subgroups of foods.

Parent and child perspectives on family out-of-home eating: a qualitative analysis

OBJECTIVE

To (i) explore the factors influencing family out-of-home (OH) eating events and (ii) identify possible opportunities for food businesses to support families in making healthier OH choices.

DESIGN

Focus group discussions were conducted with parents (six to eight participants per group) and friendship pair discussions (informal interviews with two children who are friends) were conducted with children (5-12 years) throughout the island of Ireland. Both discussions were audio-recorded and analysed using a thematic content analysis.

SETTING

Eight focus groups and sixteen friendship pairs were conducted in Northern Ireland and sixteen focus groups and thirty-two friendship pairs were conducted in the Republic of Ireland.

SUBJECTS

Purposive sampling was used to recruit a sample of non-related parents and children that represented equal numbers of gender, age, socio-economic status and demographic backgrounds.

RESULTS

The main, overarching theme was that families perceived OH eating to be a treat, while health was not currently a key priority for many parents and children. Children were reported to have most responsibility for their own food choice decisions in this environment, with taste and food neophobia having the greatest influences. Parents believed that if food businesses could meet parent and child priorities in addition to health influences, e.g. change cooking methods, and increase flexibility, then families would be more likely to patronise these establishments.

CONCLUSIONS

The entire family OH eating experience needs to be considered when developing public health interventions and this research has highlighted key opportunities that caterers could employ to support healthier family OH food choices.

Findings from the Quebec Family Study on the Etiology of Obesity: Genetics and Environmental Highlights

The Quebec Family Study (QFS) was an observational study with three cycles of data collection between 1979 and 2002 in Quebec City, Canada. The cohort is a mixture of random sampling and ascertainment through obese individuals. The study has significantly contributed to our understanding of the determinants of obesity and associated disease risk over the past 35 years. In particular, the QFS cohort was used to investigate the contribution of familial resemblance and genetic effects on body fatness and behaviors related to energy balance. Significant familial aggregation and genetic heritability were reported for total adiposity, fat-free mass, subcutaneous fat distribution, abdominal and visceral fat, resting metabolic rate, physical activity level and other behavioral traits. The resources of QFS were also used to study the contribution of several nontraditional (non-caloric) risk factors as predictors of excess body weight and gains in weight and adiposity over time, including low calcium and micronutrient intake, high disinhibition eating behavior trait, and short sleep duration. An important finding relates to the interactions between dietary macronutrient intake and exercise intensity on body mass and adiposity.

Parental eating behavior traits are related to offspring BMI in the Québec Family Study

OBJECTIVE

Parental eating behavior traits have been shown to be related to the adiposity of their young children. It is unknown whether this relationship persists in older offspring or whether rigid or flexible control are involved. The objective of this study was to test the hypothesis that parental eating behavior traits, as measured by the Three-Factor Eating Questionnaire (TFEQ), are related to offspring body weight.

METHODS

Cross-sectional anthropometric and TFEQ data from phase 2 and 3 of the Québec Family Study generated 192 parent-offspring dyads (offspring age range: 10-37 years). Relationships were adjusted for offspring age, sex and reported physical activity, number of offspring per family and parent body mass index (BMI).

RESULTS

In all parent-offspring dyads, parental rigid control and disinhibition scores were positively related to offspring BMI (r=0.17, P=0.02; r=0.18, P<0.01, respectively). There were no significant relationships between cognitive restraint (P=0.75) or flexible control (P=0.06) with offspring BMI. Regression models revealed that parent disinhibition mediated the relationship between parent and offspring BMI, whereas rigid control of the parent moderated this relationship. The interaction effect between parental rigid control and disinhibition was a significant predictor of offspring BMI (β=0.13, P=0.05).

CONCLUSION

Family environmental factors, such as parental eating behavior traits, are related to BMI of older offspring, and should be a focus in the prevention of obesity transmission within families.

Change in maternal body mass index is associated with offspring body mass index: a 21-year prospective study

PURPOSE

To examine whether changes in maternal overweight and obesity from pre-pregnancy to two decades postpartum predict the body mass index (BMI) of adult offspring.

METHODS

We used a subsample of 1997 mother-offspring pairs from the 7,223 original cohorts of women who gave birth in Brisbane, Australia, between 1981 and 1984. Multiple linear regression and multinomial logistic regression were used to examine the relationship between change in maternal BMI from pre-pregnancy to 21-year postpartum, and offspring BMI at 21-year, adjusting for potential confounding factors.

RESULTS

At 21-year postpartum, 31.15 % mothers were overweight and a further 30.80 % were obese. Mothers gained a mean weight of 16.07 kg over the 21 year. We found that the offspring of mothers who became overweight or remained overweight at 21-year postpartum were at greater risk of being overweight and obese at 21 years. In the adjusted model, offspring of mothers who had normal BMI before pregnancy but became overweight by 21-year postpartum were (odds ratio) 1.72 (95 % CI = 1.20, 2.47) times more likely to be overweight. Compared to offspring of mothers who maintained normal weight over two decades, offspring of mothers who remained persistently overweight were (odds ratio) 5.39 (95 % CI = 3.50, 8.30) times more likely to be obese by age 21 year.

CONCLUSIONS

The findings of this study suggest that long-term changes in maternal BMI from pre-pregnancy to 21-year postpartum are independently associated with BMI in their young adult offspring.

OVERWEIGHT AND OBESITY IN RURAL GIRLS FROM POLAND: CHANGES BETWEEN 1987 AND 2001

Several studies have documented increased prevalence of overweight and obesity in inhabitants of rural regions, but determinants of their prevalence are complex and not always in one direction. The aim of this study was to estimate both the prevalence and extent of overweight and obesity among rural girls in Poland between 1987 and 2001, as well as to assess differentiation of the phenomenon between regions of different social structures. The data come from two series of cross-sectional studies; the first in 1987 included 7764 girls, and the second in 2001 included 9431 girls aged 9–18. Body mass index (according to the International Obesity Task Force, IOTF) and the EOW index (extent of overweight), which shows by what mean BMI value the overweight boundaries are exceeded, were calculated. Overweight and obesity prevalences in the whole sample, were, respectively, 14.9% and 2.7% in 1987 and 15.5% and 2.5% in 2001, but significant differentiation in the direction of the changes was observed between the examined regions. In one of them, characterized by sudden, mass and long-term unemployment, there was a considerable decrease in overweight and obesity prevalence, whereas in a relatively wealthier region no changes were observed during the 14-year period. Two other regions with a relatively low standard of living and low incomes and education status presented a significant increase in overweight and obesity prevalence. The EOW index increased from 1.9 to 2.1 in the whole examined sample, and it also confirmed significant differences in expansion of overweight and obesity between the examined regions. The complex character of political and socioeconomic changes in Poland during the 1990s has resulted in two-directional changes in biological measures of living conditions. The analysis of the whole sample led to different results in comparison to separate analyses of each of the examined regions.

Prevalence and familial patterns of night eating in the Québec adipose and lifestyle investigation in youth (QUALITY) study

The prevalence and familial patterns of night eating syndrome (NES) in families enrolled in the Québec Adipose and Lifestyle InvesTigation in Youth (QUALITY) study was examined. Families (n = 395; one child, mother, and father for whom at least one parent was obese or had abdominal obesity) completed the Night Eating Questionnaire (NEQ) as part of a longitudinal study on the development of metabolic disease in children at risk for obesity. Responses on the NEQ were used to establish a diagnosis of NES and to determine the correlation and heritability of NES symptoms in families. Using comprehensive research diagnostic criteria, full threshold NES was rare: 0% of children, 0.5% of mothers, and 0.3% of fathers met criteria. When controlling for age, sex, and BMI, NEQ scores of spouses were not significantly correlated, but mothers' NEQ scores were significantly correlated with the scores of both sons (r = 0.19, P < 0.001) and daughters (r = 0.15, P = 0.05). The heritability of NEQ scores was 0.24 when controlling for age, sex, and BMI. These findings replicate previous research suggesting a low prevalence of night eating behavior in children and the aggregation of NES in families.

Fat brains, greedy genes, and parent power: a biobehavioural risk model of child and adult obesity

We live in a world replete with opportunities to overeat highly calorific, palatable foods - yet not everyone becomes obese. Why? We propose that individuals show differences in appetitive traits (e.g. food cue responsiveness, satiety sensitivity) that manifest early in life and predict their eating behaviours and weight trajectories. What determines these traits? Parental feeding restriction is associated with higher child adiposity, pressure to eat with lower adiposity, and both strategies with less healthy eating behaviours, while authoritative feeding styles coincide with more positive outcomes. But, on the whole, twin and family studies argue that nature has a greater influence than nurture on adiposity and eating behaviour, and behavioural investigations of genetic variants that are robustly associated with obesity (e.g. FTO) confirm that genes influence appetite. Meanwhile, a growing body of neuroimaging studies in adults, children and high risk populations suggests that structural and functional variation in brain networks associated with reward, emotion and control might also predict appetite and obesity, and show genetic influence. Together these different strands of evidence support a biobehavioural risk model of obesity development. Parental feeding recommendations should therefore acknowledge the powerful - but modifiable - contribution of genetic and neurological influences to children's eating behaviour.

Exploring the factors contributing to sibling correlations in BMI: a study using the Panel Study of Income Dynamics

Understanding the mechanisms contributing to correlated BMI outcomes in a social network such as siblings will help policy makers reduce the burden of disease associated with obesity. There are two potential mechanisms explaining correlated BMI outcomes in a biologically related social network: (i) time constant factors such as genetic heritability and habits formed during childhood and (ii) factors that change over time some of which are dependent on the frequency of interactions between the social network, for example, social norms shaped by the social network's shifting attitudes towards weight and behaviors related to weight, or environmental factors like opportunities for exercise. This study aims to distinguish between time constant factors from factors that are likely to change over time to gain a better understanding of the mechanisms explaining the correlation in sibling BMI. We exploit data from the Panel Study of Income Dynamics (PSID) over 1999-2007 estimating the correlation in BMI for adult siblings who currently live in separate households but grew-up in the same household and adolescent siblings currently living in the same household to isolate the influence of factors that change over time. The findings indicate that time constant factors explain some of the overall correlation in sibling BMI for both cohorts of siblings. Factors that change over time only significantly impact on the overall correlation in BMI for adolescent siblings suggesting if there is a social network influence on correlations in BMI this is facilitated by sharing the same household.

Genetic and Environmental Influences on Eating Behavior - A Study of Twin Pairs Reared Apart or Reared Together

This study examined the relative influence of genetic versus environmental factors on specific aspects of eating behavior. Adult monozygotic twins (22 pairs and 3 singleton reared apart, 38 pairs and 9 singleton reared together, age 18–76 years, BMI 17–43 kg/m²) completed the Three Factor Eating Questionnaire. Genetic and environmental variance components were determined for the three eating behavior constructs and their subscales using model-fitting univariate and multivariate analyses. Unique environmental factors had a substantial influence on all eating behavior variables (explaining 45–71% of variance), and most strongly influenced external locus for hunger and strategic dieting behavior of restraint (explaining 71% and 69% of variance, respectively). Genetic factors had a statistically significant influence on only 4 variables: restraint, emotional susceptibility to disinhibition, situational susceptibility to disinhibition, and internal locus for hunger (heritabilities were 52%, 55%, 38% and 50%, respectively). Common environmental factors did not statistically significantly influence any variable assessed in this study. In addition, multivariate analyses showed that disinhibition and hunger share a common influence, while restraint appears to be a distinct construct. These findings suggest that the majority of variation in eating behavior variables is associated with unique environmental factors, and highlights the importance of the environment in facilitating specific eating behaviors that may promote excess weight gain.

Heritability of Body Mass Index: A Comparison Between The Netherlands and Spain

Ahigh body mass index (BMI) is commonly used as an index of overweight and obesity. There is persistent evidence of high heritability for variation in BMI, but the effects of common environment appear inconsistent across different European countries. Our objective was to compare genetic and environmental effects on BMI in a sample of twins from two different European countries with distinct population and cultural backgrounds. We analysed data of adult female twins from the Netherlands Twin Register (222 monozygotic [MZ] and 103 dizygotic [DZ] pairs) and the Murcia Twin Register (Spain; 202 MZ and 235 DZ pairs). BMI was based on self-reported weight and height. Dutch women were taller and heavier, but Spanish women had a significantly higher mean BMI. The age related weight increase was significantly stronger in the Spanish sample. Genetic analyses showed that genetic factors are the main contributors to variation in height, weight, and BMI, within both countries. For height and weight, estimates of genetic variances did not differ, but for height, the estimate for the environmental variance was significantly larger in Spanish women. For BMI, both the genetic and the environmental variance components were larger in Spanish than in Dutch women.

Social network concordance in food choice among spouses, friends, and siblings

OBJECTIVES

We investigated whether eating behaviors were concordant among diverse sets of social ties.

METHODS

We analyzed the socioeconomic and demographic distribution of eating among 3418 members of the Framingham Heart Study observed from 1991 to 2001. We used a data-classification procedure to simplify choices into 7 nonoverlapping patterns that we matched with information on social network ties. We used correlation analysis to examine eating associations among 4 types of peers (spouses, friends, brothers, and sisters). Longitudinal multiple logistic regression was used to evaluate evidence for peer influences on eating.

RESULTS

Of all peer types, spouses showed the strongest concordances in eating patterns over time after adjustment for social contextual factors. Across all peers, the eating pattern most likely to be shared by socially connected individuals was "alcohol and snacks." Models estimating one's current eating pattern on the basis of a peer's prior eating provided supportive evidence of a social influence process.

CONCLUSIONS

Certain eating patterns appeared to be socially transmissible across different kinds of relationships. These findings represent an important step in specifying the relevant social environment in the study of health behaviors to include eating.

Links between mothers' and children's disinhibited eating and children's adiposity

Few studies have examined relationships between parents' and children's specific disinhibited eating behaviors. We investigated links among mothers' and children's binge/loss of control eating, eating in the absence of hunger, and children's adiposity in 305 non-treatment-seeking youth, aged 8-17 years (13.62±2.65 years; 49.8% female) and their mothers. Youths' loss of control eating and eating in the absence of hunger were assessed by interview and self-report questionnaire. Children's adiposity was assessed with BMI-z and air displacement plethysmography. Maternal binge eating, eating in the absence of hunger and highest, non-pregnant BMI were self-reported. In structural equation models controlling for mothers' BMI, mothers' binge eating related to children's loss of control eating, and mothers' eating in the absence of hunger related to children's eating in the absence of hunger. Mothers' binge eating and children's eating in the absence of hunger were unrelated, as were mothers' eating in the absence of hunger and children's loss of control. Further, mothers' binge eating was indirectly related to children's adiposity through children's loss of control eating. Likewise, mothers' eating in the absence of hunger indirectly related to children's adiposity through children's eating in the absence of hunger. Mothers and children share similar, specific disinhibited eating styles.

Family history in public health practice: a genomic tool for disease prevention and health promotion

Family history is a risk factor for many chronic diseases, including cancer, cardiovascular disease, and diabetes. Professional guidelines usually include family history to assess health risk, initiate interventions, and motivate behavioral changes. The advantages of family history over other genomic tools include a lower cost, greater acceptability, and a reflection of shared genetic and environmental factors. However, the utility of family history in public health has been poorly explored. To establish family history as a public health tool, it needs to be evaluated within the ACCE framework (analytical validity; clinical validity; clinical utility; and ethical, legal, and social issues). Currently, private and public organizations are developing tools to collect standardized family histories of many diseases. Their goal is to create family history tools that have decision support capabilities and are compatible with electronic health records. These advances will help realize the potential of family history as a public health tool.

Eating behaviors of children in the context of their family environment

Both a family history of obesity and early childhood obesity have been identified as strong predictors of adult obesity risk. The finding that parental obesity, maternal obesity in particular, increases a child's risk for developing obesity suggests that either shared genes, or environment, or likely a combination of both may promote overeating and excessive weight gain in children. Parents not only create food environments for children's early experiences with food and eating, but they also influence their children's eating by modeling their own eating behaviors, taste preferences, and food choices. Thus, it is important to identify intermediary behavioral eating traits which promote overeating and obesity in children and to determine the extent to which associations between eating traits and excessive weight gain in children may be influenced by genetic factors, environmental factors, or both. Behavioral genetic methods can be used to help partition genetic and environmental sources of variability in behavioral traits. The focus of this paper is to review and discuss findings from both short-term experimental and prospective cohort studies on eating behaviors of children at various stages in their lives. Select child eating traits and parent-child resemblances in eating will be further examined in the context of children's home environment and their familial predisposition to obesity. The paper represents an invited review by a symposium, award winner or keynote speaker at the Society for the Study of Ingestive Behavior [SSIB] Annual Meeting in Portland, July 2009.

Nature and nurture in infant appetite: analysis of the Gemini twin birth cohort

BACKGROUND

A strong genetic influence on appetitive traits has been shown in children and adults, but no studies have examined appetite in early infancy, even though avidity of appetite has been linked with a higher risk of obesity.

OBJECTIVE

The objective was to investigate the heritability in early infancy of 4 appetitive traits that have been shown to be heritable later in childhood.

DESIGN

Data are from the Gemini Study, a population-based sample of twins (n = 2402 pairs) born in England and Wales in 2007. To describe their children's eating behavior during the first 3 mo of life while they were still exclusively milk fed, the parents of the twins completed 4 subscales of the Baby Eating Behavior Questionnaire: "enjoyment of food," "food responsiveness," "slowness in eating," and "satiety responsiveness." Heritability was estimated by using quantitative genetic model fitting.

RESULTS

Heritability was high for slowness in eating (84%; 95% CI: 83%, 86%) and satiety responsiveness (72%; 95% CI: 65%, 80%) and moderate for food responsiveness (59%; 95% CI: 52%, 65%) and enjoyment of food (53%; 95% CI: 43%, 63%).

CONCLUSIONS

Genetically determined variability in appetitive traits may be one of the pathways through which genes influence the growth rate in infancy. Early identification of infants with avid appetites may make it possible to implement strategies to attenuate the expression of these traits before excessive weight gain occurs.

Pharmacological management of appetite expression in obesity

For obese individuals, successful weight loss and maintenance are notoriously difficult. Traditional drug development fails to exploit knowledge of the psychological factors that crucially influence appetite, concentrating instead on restrictive criteria of intake and weight reduction, allied to a mechanistic view of energy regulation. Drugs are under development that may produce beneficial changes in appetite expression in the obese. These currently include glucagon-like peptide-1 analogs such as liraglutide, an amylin analog davalintide, the 5-HT(2C) receptor agonist lorcaserin, the monoamine re-uptake inhibitor tesofensine, and a number of combination therapies such as pramlintide and metreleptin, bupropion and naltrexone, phentermine and topiramate, and bupropion and zonisamide. However, the effects of these treatments on eating behavior remain poorly characterized. Obesity is typically a consequence of overconsumption driven by an individual's natural sensitivity to food stimuli and the pleasure derived from eating. Intuitively, these processes should be effective targets for pharmacotherapy, and behavioral analysis can identify drugs that selectively affect desire to eat, enjoyment of eating, satiation or postmeal satiety. Rational interventions designed specifically to modulate these processes could limit the normally aversive consequences of caloric restriction and maximize an individual's capacity to successfully gain control over their appetite.

Research opportunities with curanderos to address childhood overweight in Latino families

Curanderos are consulted as an adjunct or alternative to biomedical health care in the greater southwest, although the extent of their involvement in obesity prevention and treatment is poorly understood. Seven curanderos participated in audiotaped interviews about their work with families and beliefs about childhood feeding and overweight. Themes reflected curanderos' beliefs about their practice and childhood obesity. Curanderos approach their work as a calling, emphasizing elements from nature in etiology and cure. From the curandero's standpoint, essential elements of obesity management must acknowledge the socially marginalized experiences of Latinos. We encountered working with curanderos as problematic, and this likely reflected our differing personal characteristics and a tension between our healing professions. Curanderos could serve as collaborators in childhood obesity interventions if we craft health messages and delivery modes that resonate with Latino families and address ethical and communication issues on the research team.

Genetic and environmental influences on restrained eating behavior

OBJECTIVE

We examined the relative contributions of genetic and environmental influences to restrained eating.

METHOD

Restrained eating was assessed by the Restraint Scale in a survey mailed to all twins enrolled in the University of Washington Twin Registry. We used structural equation modeling to estimate genetic and nongenetic contributions to restrained eating.

RESULTS

1,196 monozygotic (MZ), 456 same-sex dizygotic (DZ) twins, and 447 opposite-sex twins were included in analyses. Restraint Scale scores were more closely correlated in MZ twins (r(male) = .55, r(female) = .55) than in same-sex DZ twins (r(male) = .31, r(female) = .19). Based on structural equation modeling, the estimated heritability for restrained eating, adjusted for body mass index (BMI) and sex, was 43% (95% confidence interval 35-50%). There was little evidence for common environmental effects.

DISCUSSION

These results indicate an inherited component to restrained eating. Genes could influence restrained eating directly or through inherited mediators such as personality factors or tendencies to gain weight.

Alimentary Epigenetics: A Developmental Psychobiological Systems View of the Perception of Hunger, Thirst and Satiety

Hunger, thirst and satiety have an enormous influence on cognition, behavior and development, yet we often take for granted that they are simply inborn or innate. Converging data and theory from both comparative and human domains, however, supports the conclusion that the phenomena hunger, thirst and satiety are not innate but rather emerge probabilistically as a function of experience during individual development. The metatheoretical perspective provided by developmental psychobiological systems theory provides a useful framework for organizing and synthesizing findings related to the development of the perception of hunger, thirst and satiety, or alimentary interoception. It is argued that neither developmental psychology nor the psychology of eating and drinking have adequately dealt with the ontogeny of alimentary interoception and that a more serious consideration of the species-typical developmental system of food and fluid intake and the many modifications that have been made therein is likely necessary for a full understanding of both alimentary and emotional development.

Eating rate is a heritable phenotype related to weight in children

BACKGROUND

There is growing interest in the heritability of behavioral phenotypes related to adiposity. One potential candidate is the speed of eating, although existing evidence for an association with weight is mixed.

OBJECTIVE

We aimed to assess the speed of eating in a sample of 10-12-y-old children to test the hypotheses that higher eating rate is related to greater adiposity and that eating rate is a heritable characteristic.

DESIGN

Video data of 254 twin children eating a standard meal at home were used to record eating rate (bites/min) and changes in eating rate across the 4 quarters of the meal. Adiposity was indexed with body mass index SD scores relative to British 1990 norms; for some analyses, children were categorized into groups of overweight or obese and into 2 subgroups of normal-weight (lower normal-weight or higher normal-weight) for comparison of the eating rate within the normal range as well as between clinical and nonclinical groups. All analyses controlled for clustering in twin pairs. Heritability of eating rate was modeled by using standard twin methods.

RESULTS

There was a significant linear association across the 3 weight groups for eating rate (P = 0.010), and regression analyses showed that eating rate increased by 0.18 bites/min for each 1-unit increase in body mass index SD score (P = 0.005). The heritability of eating rate was high (0.62; 95% CI: 0.45, 0.74). There was no association between weight group and a change (ie, deceleration) in eating rate over the mealtime.

CONCLUSION

Faster eating appears to be a heritable behavioral phenotype related to higher weight.

Gender, marital status, and commercially prepared food expenditure

OBJECTIVE

Assess how per capita expenditure on commercially prepared food as a proportion of total food expenditure varies by the sex and marital status of the head of the household.

DESIGN

Prospective cohort study, data collected by the United States Bureau of Labor Statistics 2004 Consumer Expenditure Survey.

SETTING

United States.

PARTICIPANTS

Randomly selected nationally representative sample of 5744 US citizens.

MAIN OUTCOME MEASURES

Per capita spending on commercially prepared food (dependent variable) for every $1 increase in total per capita food spending (independent variable).

ANALYSIS

Linear regressions run separately for each permutation of gender and marital status (never married, married, divorced/separated).

RESULTS

Proportionate per capita household expenditure on commercially prepared food was found to vary by marital status and gender. Households headed by unmarried men (both divorced/separated and never married) spent a significantly greater proportion of their food budget on commercially prepared food than their married male peers (38% and 60% higher, respectively). Regardless of marital status, households headed by women were found to spend approximately one-third of their total food budget on commercially prepared foods outside the home. Households headed by never married men spent 63% more per capita than those headed by never married women and households headed by divorced or separated men spent 37% more than those headed by divorced or separated women.

CONCLUSIONS AND IMPLICATIONS

Marital status is significantly related to the dietary patterns of households headed by men. In light of the high rates of divorce, separation, and delay of marriage, marriage cannot be considered an inclusive or permanent solution to changing male eating patterns. It is important that nutrition educators learn more about the dietary patterns of households headed by males outside the institution of marriage.

Eating behaviours of non-obese individuals with and without familial history of obesity

The aim of the present study was to examine whether eating behaviours and their subscales are associated with familial history of obesity (FHO) in a cohort of 326 non-obese men and women. Anthropometric measurements, eating behaviours (Three-Factor Eating Questionnaire) and dietary intakes (FFQ) have been determined in a sample of 197 women and 129 men. A positive FHO (FHO+) was defined as having at least one obese first-degree relative and a negative FHO (FHO-) as no obese first-degree relative. Men with FHO+ had higher scores of cognitive dietary restraint and flexible restraint than men with FHO-. In women, those with FHO+ had a higher score of disinhibition than women with FHO-. In both men and women, eating behaviours were not significantly associated with the number of obese family members. However, having an obese mother was associated with higher scores of cognitive dietary restraint, flexible restraint and rigid restraint in women. These findings demonstrate that eating behaviours of non-obese subjects are different according to the presence or absence of obese family members. More specifically, having an obese mother is associated with a higher dietary restraint score in women.

Disinhibition: its effects on appetite and weight regulation

Over the past 30 years, the understanding of eating behaviour has been dominated by the concept of dietary restraint. However, the development of the Three Factor Eating Questionnaire introduced two other factors, Disinhibition and Hunger, which have not received as much recognition in the literature. The objective of this review was to explore the relationship of the Disinhibition factor with weight regulation, food choice and eating disorders, and to consider its aetiology. The review indicates that Disinhibition is an important eating behaviour trait. It is associated not only with a higher body mass index and obesity, but also with mediating variables, such as less healthful food choices, which contribute to overweight/obesity and poorer health. Disinhibition is also implicated in eating disorders and contributes to eating disorder severity. It has been demonstrated that Disinhibition is predictive of poorer success at weight loss, and of weight regain after weight loss regimes and is associated with lower self-esteem, low physical activity and poor psychological health. Disinhibition therefore emerges as an important and dynamic trait, with influences that go beyond eating behaviour and incorporate other behaviours which contribute to weight regulation and obesity. The characteristics of Disinhibition itself therefore reflect many components representative of a thrifty type of physiology. We propose that the trait of Disinhibition be more appropriately renamed as 'opportunistic eating' or 'thrifty behaviour'.

Heritability of hyperphagic eating behavior and appetite-related hormones among Hispanic children

OBJECTIVE

Eating in the absence of hunger (EAH) may be a genetically influenced phenotype of overweight children, but evidence is limited. This research evaluated the heritability (h(2)) of EAH and its association with overweight among Hispanic children 5 to 18 years old. Genetic and environmental associations of EAH with overweight, fat mass, and key hormonal regulators of food intake were also evaluated.

RESEARCH METHODS AND PROCEDURES

A family design was used to study 801 children from 300 Hispanic families. Weighed food intakes were used to measure EAH after an ad libitum dinner providing 50% of estimated energy needs. Fasting ghrelin, amylin, insulin, and leptin were measured by immunoassays. Measured heights, weights, and fat mass (using DXA) were obtained. Total energy expenditure (TEE) was measured by room respiration calorimetry.

RESULTS

On average, children consumed 41% of TEE at the dinner meal, followed by an additional 19% of TEE in the absence of hunger. Overweight children consumed 6.5% more energy at dinner (p < 0.001) and 14% more energy in the absence of hunger (p < 0.001) than non-overweight children. Significant heritabilities were seen for EAH (h(2) = 0.51) and dinner intake (h(2) = 0.52) and for fasting levels of ghrelin (h(2) = 0.67), amylin (h(2) = 0.37), insulin (h(2) = 0.37), and leptin (h(2) = 0.34). Genetic correlations were seen between eating behavior and fasting hormones, suggesting common underlying genes affecting their expression.

DISCUSSION

This research provides new evidence that overweight Hispanic children exhibit elevated levels of hyperphagic eating behaviors that are influenced by genetic endowment.

Parent overweight predicts daughters' increase in BMI and disinhibited overeating from 5 to 13 years

OBJECTIVE

To assess whether parental overweight status and disinhibited overeating are predictive of daughters' accelerated weight gain and disinhibited overeating.

RESEARCH METHODS AND PROCEDURES

Participants were part of a longitudinal study of girls (N = 197) and their parents. Measured height and weight were used to calculate BMI [weight (kilograms)/height (meters)(2)]. Parents' disinhibited eating behavior was assessed using the Eating Inventory. Girls' disinhibited eating was assessed using a behavioral protocol to measure eating in the absence of hunger. Girls were classified based on parental overweight at study entry into four groups: neither, mother only, father only, or both parents overweight.

RESULTS

Girls with both parents overweight had the most rapid increases in BMI from 5 to 13 years of age; BMI increased most slowly among the neither parent overweight group, with intermediate increases in BMI among mother only and father only overweight groups. Daughters with both parents overweight at study entry were eight times more likely to be overweight at age 13, controlling for daughters' weight at age 5. Girls with both parents overweight had higher levels of disinhibited eating across all ages than all other groups. Although girls in all parental weight status groups showed increases in disinhibited eating over time, girls with both parents overweight had larger increases in disinhibited eating over time compared with all other groups.

DISCUSSION

Girls growing up in families differing in parental overweight had divergent developmental trajectories for BMI and disinhibited overeating. Findings reveal the need to focus prevention efforts on overweight parents of young children.

The Eating Inventory, body adiposity and prevalence of diseases in a quota sample of Czech adults

OBJECTIVE

To study the relationships between the Eating Inventory (EI) factors (restraint, disinhibition and hunger), body adiposity and prevalence of selected diseases in a quota sample of Czech adults.

SUBJECTS AND METHODS

The sample included 1429 men and 1624 women who were interviewed individually by trained investigators. The sample was quota representative--for gender, age, size of residential location, region and socioeconomic status in Czech adults. Anthropometric data, socioeconomic and lifestyle information were obtained. Subjects filled out the EI questionnaire. Physicians reported about subjects' morbidity.

RESULTS

Backward stepwise regression analysis revealed that restraint and disinhibition were significant predictors of body mass index (BMI) along with gender, age, parental obesity, weight loss attempts, present dieting and educational level. The same factors plus income predicted the waist circumference. BMI and waist circumference were negatively related to restraint but positively to disinhibition. According to logistic regression analysis restraint and disinhibition were significantly associated with hypertension, cardiovascular diseases and hyperlipidaemia. Diabetes was significantly related to restraint and hunger scores. The observed association between EI factors and diseases remained significant even when BMI and age were taken into account.

CONCLUSION

As shown in earlier studies, disinhibition was positively and restraint negatively associated with BMI and waist circumference. For the first time, factors of the EI were also identified as significant predictors of diseases characterizing the metabolic syndrome.

Genetics of food intake and eating behavior phenotypes in humans

This review summarizes the research advances of the past decade regarding the role of human genetic differences in energy and nutrient intake as well as in eating behavior phenotypes and selected eating disorders. The evidence for familial aggregation and heritability based on twin and nuclear family study designs is summarized. Genome-wide linkage scans and quantitative trait loci identified to date are discussed. DNA sequence variants in candidate genes are reviewed. Single genes associated with classical eating disorders are also incorporated. Epigenetic events will need to be incorporated in future studies designed to investigate the effects of DNA variants on dietary phenotypes. Understanding the relative contribution of global genetic variation and of DNA sequence variants in specific genes is important in the effort to influence dietary habits in a healthier direction.

Polymorphisms of the low-density lipoprotein receptor-related protein 5 (LRP5) gene are associated with obesity phenotypes in a large family-based association study

BACKGROUND

The low-density lipoprotein receptor-related protein 5 (LRP5) gene, essential for glucose and cholesterol metabolism, may have a role in the aetiology of obesity, an important risk factor for diabetes.

PARTICIPANTS AND METHODS

To investigate the association between LRP5 polymorphisms and obesity, 27 single-nucleotide polymorphisms (SNPs), spacing about 5 kb apart on average and covering the full transcript length of the LRP5 gene, were genotyped in 1873 Caucasian people from 405 nuclear families. Obesity (defined as body mass index (BMI) >30 kg/m(2)) and three obesity-related phenotypes (BMI, fat mass and percentage of fat mass (PFM)) were investigated.

RESULTS

Single markers (12 tagging SNPs and 4 untaggable SNPs) and haplotypes (5 blocks) were tested for associations, using family-based designs. SNP4 (rs4988300) and SNP6 (rs634008) located in block 2 (intron 1) showed significant associations with obesity and BMI after Bonferroni correction (SNP4: p<0.001 and p = 0.001, respectively; SNP6: p = 0.002 and 0.003, respectively). The common allele A for SNP4 and minor allele G for SNP6 were associated with an increased risk of obesity. Significant associations were also observed between common haplotype A-G-G-G of block 2 with obesity, BMI, fat mass and PFM with global empirical values p<0.001, p<0.001, p = 0.003 and p = 0.074, respectively. Subsequent sex-stratified analyses showed that the association in the total sample between block 2 and obesity may be mainly driven by female subjects.

CONCLUSION

Intronic variants of the LRP5 gene are markedly associated with obesity. We hypothesise that such an association may be due to the role of LRP5 in the WNT signalling pathway or lipid metabolism. Further functional studies are needed to elucidate the exact molecular mechanism underlying our finding.