Breastfeeding and later maternal risk of hypertension and cardiovascular disease - The role of overall and abdominal obesity.

In this study, we examined how any, full, and partial breastfeeding durations were associated with maternal risk of hypertension and cardiovascular disease (CVD), and how prepregnancy body mass index (BMI) and waist circumference 7 years postpartum influenced these associations. A total of 63,260 women with live-born singleton infants in the Danish National Birth Cohort (1996-2002) were included. Interviews during pregnancy and 6 and 18 months postpartum provided information on prepregnancy weight, height, and the duration of full and partial breastfeeding. Waist circumference was self-reported 7 years postpartum. Cox regression models were used to estimate hazard ratios of incident hypertension and CVD, registered in the National Patient Register from either 18 months or 7 years postpartum through 15 years postpartum. Any breastfeeding ≥4 months was associated with 20-30% lower risks of hypertension and CVD compared to <4 months in both normal/underweight and overweight/obese women. At follow-up starting 7 years postpartum, similar risk reductions were observed after accounting for waist circumference adjusted for BMI. Partial breastfeeding >2 months compared to ≤2 months, following up to 6 months of full breastfeeding, was associated with 10-25% lower risk of hypertension and CVD. Compared with short breastfeeding duration, additional partial breastfeeding was as important as additional full breastfeeding in reducing risk of hypertension and CVD. Altogether, longer duration of breastfeeding was associated with lower maternal risk of hypertension and CVD irrespective of prepregnancy BMI and abdominal adiposity 7 years after delivery. Both full and partial breastfeeding contributed to an improved cardiovascular health in mothers.

Childcare before age 6 and body mass index at age 7 years in a cohort of Danish children.

BACKGROUND: Previous studies show inconsistent associations between childcare and obesity. AIMS: Our prior work demonstrated that childcare in infancy was associated with higher weight in a cohort of Danish children. Here, we extend this work and examine childcare through 6 years and body mass index (BMI) at age 7 years. MATERIALS AND METHODS: We examined 24 714 children in the Danish National Birth Cohort who were also in the Childcare Database. We conducted multivariable linear regressions examining children prior to age 6, overall and by type (daycare, crèche, age-integrated and kindergarten), and BMI z-score at 7 years, stratifying on maternal socio-occupational status. RESULTS: A total of 19 760 (80.0%) children attended childcare before age 6. Childcare prior to age 6 was associated with BMI z-score at 7 years (0.004 units per each additional 6 months of care; 95% CI: 0.001, 0.008; p = 0.01). Childcare in a kindergarten was the only type of care associated with BMI (0.009 units; 95% CI: 0.003, 0.02; p = 0.01). For children of higher socio-occupational status mothers, childcare was associated with a 0.008 unit increase in BMI (95% CI: 0.004, 0.01; p > 0.001). CONCLUSIONS: Childcare was weakly associated with later BMI. This relationship was more pronounced in children from higher socio-occupational status mothers and children in kindergarten care.

Prenatal risk factors influencing childhood BMI and overweight independent of birth weight and infancy BMI: a path analysis within the Danish National Birth Cohort.

BACKGROUND AND OBJECTIVES: Prenatal risk factors for childhood overweight may operate indirectly through development in body size in early life and/or directly independent hereof. We quantified the effects of maternal and paternal body mass index (BMI), maternal age, socioeconomic position (SEP), parity, gestational weight gain, maternal smoking during pregnancy, caesarean section, birth weight, and BMI at 5 and 12 months on BMI and overweight at 7 and 11 years. METHODS: Family triads with information on maternal, paternal and child BMI at ages 7 (n=29 374) and 11 years (n=18 044) were selected from the Danish National Birth Cohort. Information originated from maternal interviews and medical health examinations. Path analysis was used to estimate the direct and indirect effects of prenatal risk factors on childhood BMI z-scores (BMIz per unit score of the risk factor). Logistic regression was used to examine associations with overweight. RESULTS: The strongest direct effects on BMIz at age 7 were found for maternal and paternal BMI (0.19 BMIz and 0.14 BMIz per parental BMIz), low SEP (0.08 BMIz), maternal smoking (0.12 BMIz) and higher BMIz at 5 and 12 months (up to 0.19 BMIz per infant BMIz). For BMIz at age 11 with BMIz at age 7 included in the model, similar effects were found, but the direct effects of BMIz at age 5 and 12 months were mediated through BMI at age 7 (0.62 BMIz per BMIz). Same results were found for overweight. The sum of the direct effects can be translated to approximate absolute measures: 2.4 kg at 7 years, 5.7 kg at 11 years, in a child with average height and BMI. CONCLUSIONS: Parental BMI, low SEP and smoking during pregnancy have persisting, strong and direct effects on child BMI and overweight independent of birth weight and infancy BMI.

Genetic risk scores for body fat distribution attenuate weight loss in women during dietary intervention.

OBJECTIVE: The well-established link between body fat distribution and metabolic health has been suggested to act through an impact on the remodeling capacity of the adipose tissue. Remodeling of the adipose tissue has been shown to affect body fat distribution and might affect the ability to lose weight. We aimed to study the effect of weighted genetic risk scores (GRSs) on weight loss based on single-nucleotide polymorphisms (SNPs) associated with waist-hip-ratio adjusted for body mass index (WHRadjBMI). DESIGN: We included 707 participants (533 women and 174 men) from the NUGENOB multi-center 10-week diet intervention study with weekly weight measurements. We created 3 GRSs, one including all reported WHRadjBMI SNPs (GRStotal), one including only SNPs with genome-wide significance in women or with significantly greater effect in women (GRSwomen), and one excluding SNPs in the GRSwomen (GRSmen). The data were analyzed in a mixed linear model framework. RESULTS: The GRStotal and GRSwomen attenuated weight loss in women. The effect was strongest for the GRSwomen with an effect of 2.21 g per risk allele per day (95% confidence intereval (CI) (0.90;3.52), P=0.0009). Adjustment for WHR, basal metabolic rate or diet compliance did not affect the result. The GRSs had no effect on weight loss in men. The VEGFA rs1358980-T strongly attenuated weight loss in both men and women (ß=15.95 g per risk allele per day, (3.16;26.74), P=0.013) and (ß=15.95 g per risk allele per day, (2.58;13.53), P=0.004), respectively). CONCLUSION: Our findings suggest that genetic variants influencing body fat distribution attenuate weight loss in women independently on the effect on WHR. The stronger effect of the GRSwomen implies heterogenic effects of the WHRadjBMI variants on weight loss. A strong effect of rs1358980-T in the VEGFA locus suggests that angiogenesis plays a role, but this needs confirmation from functional studies.

Should Europe follow the US and declare obesity a disease?: a discussion of the so-called utilitarian argument.

In 2013, the American Medical Association (AMA) decided to recognize obesity as a disease. One of the main arguments presented in favor of this was broadly 'utilitarian': the disease label would, it was claimed, provide more benefits than harms and thereby serve the general good. Several individuals and groups have argued that this reasoning is just as powerful in the European context. Drawing mainly on a review of relevant social science research, we discuss the validity of this argument. Our conclusion is that in a Western European welfare state, defining obesity as a disease will not on balance serve the general good, and that it is therefore more appropriate to continue to treat obesity as a risk factor. The main reasons presented in favor of this conclusion are: It is debatable whether a disease label would lead to better access to care and preventive measures and provide better legal protection in Europe. Medicalization and overtreatment are possible negative effects of a disease label. There is no evidence to support the claim that declaring obesity a disease would reduce discrimination or stigmatization. In fact, the contrary is more likely, since a disease label would categorically define the obese body as deviant.

Body mass index trajectories from 2 to 18 years - exploring differences between European cohorts.

BACKGROUND: In recent decades, there has been an increase in the prevalence of childhood overweight in most high-income countries. Within northern Europe, prevalence tends to be higher in the UK compared with the Scandinavian countries. We aimed to study differences in body mass index (BMI) trajectories between large cohorts of children from UK and Scandinavian populations. METHODS: We compared BMI trajectories in participants from the English Avon Longitudinal Study of Parents and Children born in 1991-1993 (ALSPAC) (N = 6517), the Northern Finland Birth Cohorts born in 1966 (NFBC1966) (N = 3321) and 1986 (NFBC1986) (N = 4764), and the Danish Aarhus Birth Cohort born in 1990-1992 (ABC) (N = 1920). We used multilevel models to estimate BMI trajectories from 2 to 18 years. We explored whether cohort differences were explained by maternal BMI, height, education or smoking during pregnancy and whether differences were attributable to changes in the degree of skew in the BMI distribution. RESULTS: Differences in mean BMI between the cohorts were small but emerged early and persisted in most cases across childhood. Girls in ALSPAC had a higher BMI than all other cohorts throughout childhood, e.g. compared with the NFBC1986 BMI was 2.2-3.5% higher. For boys, the difference emerging over time (comparing the two NFBC's) exceeded the differences across populations (comparing NFBC1986, ABC and ALSPAC). BMI distribution demonstrated increasing right skew with age. CONCLUSION: Population-level differences between cohorts were small, tended to emerge very early, persisted across childhood, and demonstrated an increase in the right-hand tail of the BMI distribution.

Tracking of body mass index from 7 to 69 years of age.

BACKGROUND: Heavy children have an increased risk of being overweight young adults. Whether this risk remains in late adulthood is not well-understood. We investigated body mass index (BMI; kg m(-2)) tracking from childhood to late adulthood. METHODS: From the Copenhagen School Health Records Register, 72 959 men and 25 252 women born between 1930 and 1989 with BMI values at 7 and/or 13 years and as adults were included. Using a meta-regression approach, age- and sex-specific partial correlation analyses and logistic regressions were performed. RESULTS: Correlations between BMI at 7 years and young adult ages (18-19 years) were r=0.55 for men and r=0.55 for women. At late ages (60-69 years) these were r=0.28 for men and r=0.26 for women. The correlations did not differ by birth years. Compared with normal-weight 7-year-olds, overweight children had a higher odds of overweight at 18-19 years; odds ratio (OR)=14.02 (95% confidence interval (CI): 12.14-16.19) for men and 10.46 (95% CI: 4.82-22.70) for women. At ages 60-69 years ORs were 5.46 (95% CI: 0.95-31.36) for men and 1.61 (95% CI: 0.83-3.15) for women. Correlations and ORs were stronger at age 13 years than age 7 years as expected, but the overall patterns were similar. CONCLUSIONS: BMI tracking was weaker at late adult ages than at young adult ages. Although BMI tracks across the life course, childhood BMI is relatively poor at identifying later adult overweight or obesity at ages when chronic diseases generally emerge.

Childhood body mass index and height and risk of histologic subtypes of endometrial cancer.

BACKGROUND: Endometrial cancer risk factors include adult obesity and taller stature, but the influence of size earlier in life is incompletely understood. We examined whether childhood body mass index (BMI; kg m(-2)) and height were associated with histologic subtypes of endometrial cancer. METHODS: From the Copenhagen School Health Records Register, 155 505 girls born 1930-1989 with measured weights and heights from 7 to 13 years were linked to health registers. BMI and height were transformed to age-specific z-scores. Hazard ratios (HRs) and 95% confidence intervals were estimated by Cox regressions. RESULTS: A total of 1020 endometrial cancers were recorded. BMI was non-linearly associated with all endometrial cancers, oestrogen-dependent cancers and the subtype of endometrioid adenocarcinomas; associations were statistically significant and positive above a z-score=0 and non-significant below zero. Compared with a 7-year-old girl with a BMI z-score=0, an equally tall girl who was 3.6 kg heavier (BMI z-score=1.5) had a hazard ratio=1.53 (95% confidence interval: 1.29-1.82) for endometrioid adenocarcinoma. BMI was not associated with non-oestrogen-dependent cancers, except at the oldest childhood ages. Height at all ages was statistically significant and positively associated with all endometrial cancers, except non-oestrogen-dependent cancers. At 7 years, per ~5.2 cm (1 z-score), the risk of endometrioid adenocarcinoma was 1.18 (95% confidence interval: 1.09-1.28). Among non-users of unopposed oestrogens, associations between BMI and endometrioid adenocarcinoma strengthened, but no effects on height associations were observed. CONCLUSIONS: Endometrial carcinogenesis is linked to early-life body size, suggesting that childhood BMI and height may be useful indicators for the risk of later development of endometrial cancer and might aid in the early prevention of obesity-related endometrial cancers.

Childhood body mass index and risk of schizophrenia in relation to childhood age, sex and age of first contact with schizophrenia.

UNLABELLED: Childhood leanness is associated with an increased risk of schizophrenia, but the effects of gender, age at anthropometric measurements and age at first diagnosis on this relationship are unclear. The present study aimed at elucidating these associations. METHODS: Population-based cohort study with childhood anthropometric measures obtained annually from the age of 7 to 13 years in 253,353 Danes born 1930-1976 and followed to 31 December 2010. During this period, 4936 were registered with schizophrenia. The associations of childhood BMI with risk of schizophrenia were estimated with Cox regression models. RESULTS: Childhood BMI was significantly inversely associated with risk of schizophrenia, however with different patterns among boys and girls. In boys, childhood BMI had an inverse non-linear association with schizophrenia risk dependent on age at diagnosis; in particular, a surprisingly strong association was found between leanness and later onset of schizophrenia. In girls, the risk of schizophrenia decreased linearly with increasing BMI z-score (HR: 0.93; 95% CI: 0.88-0.98). In both boys and girls, birth weight was inversely associated with later risk. In girls, but not in boys, birth weight appeared to significantly modify the associations; there was a somewhat stronger inverse association in the lowest birth weight category. CONCLUSION: Birth weight as well as childhood BMI at ages 7 through 13 years is associated with risk of schizophrenia in both genders, but with a particular high risk of late-onset in lean boys irrespective of birth weight, and in lean girls with low birth weight. If replicated, these observations may inform preventive efforts build on schizophrenia trajectories rooted in early life.

Depressive symptoms in women's midlife in relation to their body weight before, during and after childbearing years.

OBJECTIVE: This study aimed to examine how weight and weight changes related to pregnancy were associated with depressive symptoms 11-16 years after childbirth. METHOD: We followed 16,998 first-time mothers from the Danish National Birth Cohort up till 16 years after birth and estimated associations between depressive symptoms and pre-pregnancy body mass index (BMI) (kg m-2), weight changes in different time periods, and BMI-adjusted waist circumference 7 years after birth (WCBMI, cm). Depressive symptoms were estimated by the Center for Epidemiologic Studies Depression 10-item scale. Multiple logistic regression analyses were used to estimate odds ratios (OR) and 95% confidence intervals. RESULTS: Compared with normal-weight, we found that underweight, overweight and obesity were associated with greater odds of depressive symptoms (1.29, 1.24 and 1.73, respectively). Compared with weight change ±1 BMI unit during the total follow-up period, greater odds for depressive symptoms were observed with weight loss (OR 1.14, 0.96-1.36) or gain of 2-2.99 kg m-2 (OR 1.11, 0.92-1.33) or gain of ≥3 kg m-2 (OR 1.68, 1.46-1.94). WCBMI > 2.2 cm was associated with greater odds of depressive symptoms (OR 1.16, 0.99-1.36) than waist circumference as predicted by BMI. CONCLUSION: Low and high pre-pregnancy BMI, weight changes and WCBMI larger than predicted were associated with more depressive symptoms in midlife.

Prenatal exposure to vitamin-D from fortified margarine and milk and body size at age 7 years.

BACKGROUND/OBJECTIVES: Prenatal vitamin-D deficiency may be associated with increased risk of obesity later in life. Using two national vitamin-D fortification programs as the setting for a societal experiment, we investigated whether exposure to vitamin-D from fortified margarine and low-fat milk during foetal life was associated with body size at 7 years of age. SUBJECTS/METHODS: Vitamin-D fortification of margarine was mandatory in Denmark from 1961 to 1985, and voluntary fortification of low-fat milk was permitted from 1972 to 1976. Using information on body mass index (BMI) Z-score at the age of 7 years of 54,270 children, who were measured during the mandatory Copenhagen School Health examination, we compared children according to whether the mothers were pregnant during the fortification programs or not. The comparisons were performed for children born just before and after initiation or termination of margarine and milk fortification periods, respectively. In total four sets of analyses were performed. RESULTS: We observed no difference in mean BMI Z-score between children exposed to vitamin-D fortification in utero and non-exposed children. Similar results were observed for overweight and obesity. CONCLUSIONS: Prenatal exposure to vitamin-D from fortification of margarine and low-fat milk showed no association with body size at 7 years.

Childhood body mass index in relation to future risk of oesophageal adenocarcinoma.

BACKGROUND: Middle-aged obese adults are at substantially elevated risk of oesophageal adenocarcinoma. It is unclear whether this risk originates earlier in life. METHODS: We assessed associations between childhood body mass index (BMI) and height-measured annually between ages 7 and 13-with adult oesophageal adenocarcinoma in a cohort from the Copenhagen School Health Records Register. Analyses included 255 053 children born during 1930-1971. Danish Cancer Registry linkage provided outcomes. We calculated hazard ratios (HRs) and 95% confidence intervals (CIs) using Cox proportional hazards regression. RESULTS: During 5.4 million person-years of follow-up, 254 (216 males) incident oesophageal adenocarcinomas occurred. At each examined age, cancer risk increased linearly per unit BMI z-score, although associations were only statistically significant for ages 9-13. The HR for the age of 13 years was 1.31 (95% CI: 1.13, 1.51) per unit BMI z-score. Associations were similar in men and women and across birth cohorts. Childhood height was not related to cancer risk in men but was in women, although these analyses included just 38 female cases. HRs per unit height z-score at the age of 13 years were 1.04 (0.90, 1.19) in males and 1.77 (1.27, 2.47) in females, with similar results observed at the other examined ages. CONCLUSION: Individuals with higher childhood BMI were at elevated risk of oesophageal adenocarcinoma, even though these cancers occurred many decades later in life. Although the mechanisms require further investigation, our findings provide additional evidence for the long-term health risks of childhood obesity.

Early child care and obesity at 12 months of age in the Danish National Birth Cohort.

BACKGROUND/OBJECTIVES: Evidence suggests that the child care environment may be more obesogenic than the family home, and previous studies have found that child care use may be associated with obesity in children. Few studies, however, have focused on child care during infancy, which may be an especially vulnerable period. This study examined child care use in infancy and weight status at 12 months of age in a country where paid maternity leave is common and early child care is not as prevalent as in other developed countries. SUBJECTS/METHODS: We studied 27,821 children born to mothers participating in the Danish National Birth Cohort, a longitudinal study of pregnant women enrolled between 1997 and 2002, who were also included in the Childcare Database, a national record of child care use in Denmark. The exposure was days in child care from birth to 12 months. The outcomes were sex-specific body mass index (BMI) z-score and overweight/obesity (BMI ⩾ 85th percentile based on the World Health Organization classification) at 12 months. We conducted multivariable linear and logistic regression analyses examining child care use and weight outcomes. RESULTS: A total of 17,721 (63.7%) children attended child care during their first year of life. After adjustment for potential confounders, a 30-day increment of child care was associated with a modestly higher BMI z-score at 12 months (0.03 units; 95% confidence interval (CI) = 0.01, 0.05; P=0.003). Similarly, child care use was associated with increased odds of being overweight/obese at 12 months of age (odds ratio = 1.05; 95% CI = 1.01, 1.10; P=0.047). CONCLUSION: Child care in the first year of life was associated with slightly higher weight at 12 months, suggesting that child care settings may be important targets for obesity prevention in infancy.

Energy balance measurement: when something is not better than nothing.

Energy intake (EI) and physical activity energy expenditure (PAEE) are key modifiable determinants of energy balance, traditionally assessed by self-report despite its repeated demonstration of considerable inaccuracies. We argue here that it is time to move from the common view that self-reports of EI and PAEE are imperfect, but nevertheless deserving of use, to a view commensurate with the evidence that self-reports of EI and PAEE are so poor that they are wholly unacceptable for scientific research on EI and PAEE. While new strategies for objectively determining energy balance are in their infancy, it is unacceptable to use decidedly inaccurate instruments, which may misguide health-care policies, future research and clinical judgment. The scientific and medical communities should discontinue reliance on self-reported EI and PAEE. Researchers and sponsors should develop objective measures of energy balance.

Dietary protein and urinary nitrogen in relation to 6-year changes in fat mass and fat-free mass.

BACKGROUND: In contrast to the physiological expectation, observational studies show that greater protein intake is associated with subsequent body weight (BW) gain. An increase in fat-free mass (FFM) due to the anabolic effects of protein could explain this. OBJECTIVE: To examine associations between protein intake and subsequent changes in fat mass (FM) and FFM in longitudinal, observational data. DESIGN: A health examination, including measures of FM and FFM by bioelectrical impedance at baseline and follow-up 6 years later, was conducted. Diet history interviews (DHI) were performed, and 24-h urinary nitrogen collection at baseline was done. In total, 330 participants with DHI, of whom 227 had validated and complete 24-h urine collection data, were analyzed. Macronutrient energy substitution models were used. RESULTS: Mean estimated protein intake was 14.6 E% from DHI and 11.3 E% from urinary nitrogen. Estimated from DHI, FM increased 46 g per year, with every 1 E% protein substituted for fat (95% confidence interval (CI) = 13, 79; P = 0.006), and FFM increased 15 g per year (1, 30; P = 0.046). Results were similar in other substitution models. Estimated from urinary nitrogen, FM increased 53 g per year, with 1 E% protein substituted for other macronutrients (24, 81; P < 0.0005), and FFM increased 18 g per year (6, 31; P = 0.004). CONCLUSION: Within a habitual range, a greater protein intake was associated with BW gain, mostly in FM. This is in contrast to the expectations based on physiological and clinical trials, and calls for a better understanding of how habitual dietary protein influences long-term energy balance, versus how greater changes in dietary proteins may influence short-term energy balance.

Effects of body size and change in body size from infancy through childhood on body mass index in adulthood.

BACKGROUND: Weight and weight gain throughout infancy are related to later obesity, but whether the strength of the associations varies during the infancy period is uncertain. AIMS: Our aims were to identify the period of infancy when change in body weight has the strongest association with adult body mass index (BMI) and also the extent to which these associations during infancy are mediated through childhood BMI. METHODS: The Copenhagen Perinatal Cohort, in which participants were followed from birth through 42 years of age, provided information on weight at 12 months and BMI at 42 years for 1633 individuals. Information on weight at birth, 2 weeks, 1, 2, 3, 4 and 6 months was retrieved from health visitors' records and information on BMI at ages 7 and 13 years from school health records. The associations of infant weight and weight gain standard deviation scores (SDS) with adult BMI-SDS were analyzed using multiple linear regression and path analysis. RESULTS: Higher-weight-SDS at all ages from birth to an age 12 months were associated with higher-BMI-SDS at 42 years (regression coefficients 0.08-0.12). Infant weight gain-SDS was associated with greater BMI-SDS at 42 years only between birth and 3 months (0.09, 95% confidence intervals (CI) 0.04, 0.15) driven by an association between 2 and 3 months (0.12, 95% CI: 0.04, 0.20). The latter was partly mediated through later BMI in the path analysis. Infant weight gain-SDS between 3 and 12 months was not associated with greater BMI-SDS at 42 years. CONCLUSIONS: Faster weight gain during only the first 3 months of infancy was associated with increased adult BMI, although not in a consistent monthly pattern. Adult BMI is more sensitive to high weight gain during early infancy than late infancy, but not specifically to the first month of life.

Childhood body mass index and the risk of prostate cancer in adult men.

BACKGROUND: Prostate cancer aetiology is poorly understood. It may have origins early in life; previously we found a positive association with childhood height. The effects of early life body mass index (BMI; kg m(-2)) on prostate cancer remain equivocal. We investigated if childhood BMI, independently and adjusted for height, is positively associated with adult prostate cancer. METHODS: Subjects were a cohort of 125208 boys formed from the Copenhagen School Health Records Register, born 1930-1969 with height and weight measurements at 7-13 years. Cases were identified through linkage to the Danish Cancer Registry. Cox proportional hazards regressions were performed. RESULTS: Overall, 3355 men were diagnosed with prostate cancer. Body mass index during childhood was positively associated with adult prostate cancer. The hazard ratio of prostate cancer was 1.06 (95% confidence interval (CI): 1.01-1.10) per BMI z-score at age 7, and 1.05 (95% CI: 1.01-1.10) per BMI z-score at age 13. Estimates were similar and significant at all other ages. However, adjustment for childhood height attenuated the associations at all but the youngest ages as most estimates became nonsignificant. CONCLUSIONS: These results suggest that at most childhood ages, BMI does not confer an additional risk for prostate cancer beyond that of height.

Functional body composition and related aspects in research on obesity and cachexia: report on the 12th Stock Conference held on 6 and 7 September 2013 in Hamburg, Germany.

The 12th Stock Conference addressed body composition and related functions in two extreme situations, obesity and cancer cachexia. The concept of 'functional body composition' integrates body components into regulatory systems relating the mass of organs and tissues to corresponding in vivo functions and metabolic processes. This concept adds to an understanding of organ/tissue mass and function in the context of metabolic adaptations to weight change and disease. During weight gain and loss, there are associated changes in individual body components while the relationships between organ and tissue mass are fixed. Thus an understanding of body weight regulation involves an examination of the relationships between organs and tissues rather than individual organ and tissue masses only. The between organ/tissue mass relationships are associated with and explained by crosstalks between organs and tissues mediated by cytokines, hormones and metabolites that are coupled with changes in body weight, composition and function as observed in obesity and cancer cachexia. In addition to established roles in intermediary metabolism, cell function and inflammation, organ-tissue crosstalk mediators are determinants of body composition and its change with weight gain and loss. The 12th Stock Conference supported Michael Stocks' concept of gaining new insights by integrating research ideas from obesity and cancer cachexia. The conference presentations provide an in-depth understanding of body composition and metabolism.