BMI may overestimate the prevalence of obesity among women of lower socioeconomic status

Associations between maternal adiposity and appetite-regulating hormones in human milk are mediated through maternal circulating concentrations and might affect infant outcomes

Background

Appetite-regulating hormones (ARH) in human milk (HM) are suggested to affect infants’ milk intake and possibly infant growth. Maternal adiposity might contribute to higher levels of ARH in HM, either from the mammary gland or from raised circulating levels due to higher adiposity. Counterfactual-based mediation analysis can define indirect and direct effects between HM ARH and maternal and infant factors, and might be an important tool when investigating the mother-milk-infant triad.

Objective

We aim to investigate whether potential associations between (1) maternal adiposity and HM ARH and (2) HM ARH and infant milk intake and growth are mediated through maternal and infant plasma ARH, respectively.

Materials and methods

Maternal and infant anthropometry and body composition, HM and blood samples were collected from 223 mother-infant dyads participating in the Mother, Infant and Lactation Quality study at three postpartum visits from 1 to 8.49 months. Leptin, insulin and adiponectin were analyzed using immunoassays. Mediation analyses using linear mixed-effect models were applied to investigate the direct and indirect effects through maternal and infant plasma hormone concentrations.

Results

A positive association between maternal body-mass-index (BMI) and HM leptin was mediated by maternal plasma leptin by 29% when fixing BMI to < 25 kg/m², and through 51% when fixing BMI to ≥ 25 kg/m² (p_interaction < 0.01). There was no mediated effect through plasma insulin in the association between BMI and HM insulin (p = 0.068). We found negative and positive associations between HM insulin and total milk intake and infant weight, respectively, however, these diminished in mediation analyses with reduced sample sizes.

Conclusion

Our main results suggest that the association between maternal adiposity and HM leptin was mediated through circulating leptin to a stronger degree for mothers with overweight compared to mothers with normal-weight. This indicates that excess maternal adiposity, and the resulting rise of circulating leptin and possible concomitant low-grade inflammation, may be reflected in HM composition.

Clinical trials registry number

NCT03254329.

Prevalence of Obesity and Overweight among Adults in the Middle East Countries from 2000 to 2020: A Systematic Review and Meta-Analysis

BACKGROUND

Obesity has become a significant public health issue worldwide, and it is a major risk factor for many noncommunicable diseases. This systematic review aimed to identify the prevalence of obesity and overweight in the Middle East region and different countries in this region.

MATERIALS AND METHODS

PubMed, Google Scholar, and MEDLINE databases were searched from 2000-2020 to identify relevant studies in the Middle East area. The survey was carried out using combinations of Medical Subject Headings (Mesh) keywords like "body mass index", "obesity", "overweight", "prevalence", "Middle-East", and "Countries in the Middle East area". Analysis of the data was done using STATA-14, and a random-effects model was used to estimate the pooled prevalence.

RESULTS

A total of 101 studies with 698905 participants have been identified that met inclusion criteria for this meta-analysis. The pooled estimates of the prevalence of obesity and overweight in the Middle East area were 21.17 (95% CI: 17.05-26.29) and 33.14 (95% CI: 26.87-40.87), respectively. The findings showed that obesity prevalence increased with age so that the highest prevalence of obesity and overweight was observed in people >40 years old. Obesity prevalence in the Middle East area remained steady between 2000-2006 and 2014-2020 (23%). During these time intervals, the prevalence of overweight decreased from 34.83 (95% CI: 32.40-37.45) to 32.85 (95% CI: 31.39-34.38).

CONCLUSIONS

Despite the relative stabilization of the overweight and obesity trend in the Middle East, current interventions to combat the overweight epidemic need to be maintained and strengthened because the prevalence of overweight and obesity in this region is still very high. The prevalence of obesity increases with age so that people over 40 have the highest percentage of obesity and overweight. Therefore, implementing intervention programs to prevent and control obesity and overweight in the Middle East is essential.

A clinical model for identifying an inflammatory phenotype in mood disorders

Increasingly, clinical research has found inflammatory correlates of psychiatric disorders, particularly mood symptomatology. Biological measures may provide greater precision in many cases and may capture clinically-relevant inflammatory signposts, such as central obesity risk, inflammation-associated co-morbid medical conditions, or proinflammatory lifestyle choices. In order to expand understanding of the role of inflammation in mood disorders, we propose a more inclusive clinical model for capturing an inflammatory phenotype of depression by identifying clinically-relevant inflammatory phenotypes grounded in biology. Our model includes chronic conditions and lifestyle behaviors associated with clinically elevated inflammation in mood disorders. Elements of this "inflamed depression" model include: obesity, low HDL concentrations, elevated triglyceride concentrations, chronically elevated blood pressure, clinical diagnosis of hypothyroidism, migraines, rheumatoid arthritis, adult onset diabetes, inflammatory bowel diseases, inflammatory skin conditions, and lifestyle factors including smoking cigarettes and chronic stress.

Economic growth and obesity in South African adults: an ecological analysis between 1994 and 2014

Background

To assess the trend associations between South Africa's economic growth using various economic growth indicators (EGIs) with adult obesity prevalence over a specified period of time. Data for obesity levels reported were obtained from national surveys conducted in South African adults in 1998, 2003 and 2012. EGIs incorporated in the current analysis were obtained from the World Bank and IHS Global insight databases. Obesity prevalence is presented by gender, urbanisation level and ethnicity. EGIs congruent to the time points where obesity data are available are presented. Unadjusted time trend plots were applied to assess associations between obesity prevalence and EGIs by gender, urbanisation level and ethnicity. Females present higher levels of obesity relative to males for all time points. For both males and females, an overall increase in prevalence was observed in both rural and urban settings over-time, with urban dwellers presenting higher obesity levels. An overall increase in Gross Domestic Product (GDP) per capita and Household Final Consumption Expenditure (HFCE) per capita was observed. The Gini coefficient for all ethnicities except the White population increased between 1998 and 2003 but declined by 2012. Overtime per capita GDP and HFCE increased with increasing obesity prevalence in both genders. The trend association between the Gini coefficient for all ethnicities and obesity prevalence was similar for both genders in that as the Gini coefficient increased obesity prevalence declined, and when the coefficient decreased obesity prevalence increased. Trend associations exist between South Africa's economic growth and adult obesity.

Adolescent BMI at Northern Israel: From Trends, to Associated Variables and Comorbidities, and to Medical Signatures

The increasing prevalence of abnormal body mass index (BMI), mainly obesity, is becoming a significant public health problem. This cross-sectional study aimed to provide a comprehensive view of secular trends of BMI, and the associated socio-demographic variables and comorbidities among adolescents with abnormal BMI. Individuals of the study population were born mainly between 1970 and 1993, and were examined at 16 to 19 years of age during the years 1987 to 2010, at 1 conscription center in the northern district of Israel.The study population included 113,694 adolescents. Univariate and multivariable logistic regression models were used to investigate the associations between BMI categories, socio-demographic variables, and medical conditions.A downward trend in the prevalence of normal BMI among both male and female adolescents was obtained, while trends of overweight and obesity (in both genders) and underweight (only among females) rose. Socio-demographic variables such as religion, education, family-related parameters, residential environment, country of birth, and origin were all associated with different risks for abnormal BMI. Obesity was associated with higher risk for hyperlipidemia, endocrine disorders (only in males), knee disorders, and hypertension type I + II (in both genders). Overweight was associated with knee disorders (only in females). Underweight, exclusively in males, was associated with increased risk for endocrine disorders, proteinuria, and cardiac disorders. Hierarchical clustering analysis revealed the intricate relations between gender, BMI, and medical signatures. It brought to light novel clusters of diseases that were abundant among populations having above-normal BMI or underweight males. Furthermore, above-normal BMI was associated with a lower rate of cardiac anomalies and scoliosis/kyphosis, whereas being underweight was associated with a lower risk for hypertension and flat foot.This study provides a reliable and in-depth view of secular trends in height, weight, and BMI of male and female adolescents. It supports previous associations between abnormal BMI and demographic variables and comorbidities, while uncovering novel associations, mainly regarding medical signatures of each gender-BMI group. This might lead to better monitoring, early detection, prevention, and treatment of various conditions associated to abnormal BMI categories and gender groups.

Karma eaters: the politics of food and fat in women's land communities in the United States

Why is thinness so important among women who have largely rejected mainstream definitions of femininity? The idea of health has great cultural power and has come to symbolize not simply bodily but also spiritual, social, and moral well-being. These ideas permeate U.S. culture, and in women's land communities, the virtue of hunger and the morality of health take on differently inflected but no less potent meanings. Ironically, in a context where women reject many gender restrictions--restrictions increasingly, as Sandra Bartky notes, focused on the female body-the importance of the thin (and thus properly feminine) body persists through the symbolism of health and virtue.

Height differences and the associations between food insecurity, percentage body fat and BMI among men and women

OBJECTIVE

The present study examined the associations between adult food insecurity (FI) and percentage body fat (%BF) and BMI, stratified by height (HT).

DESIGN, SETTING AND SUBJECTS

%BF, HT and BMI of 2117 men and 1909 women in the National Health and Nutrition Examination Survey 1999-2002 were analysed in relation to adult food security status using multiple regression procedures.

RESULTS

Compared with the fully food-secure, men's %BF, BMI and HT were lower as FI intensified. Marginal food security among women was associated with 1.3 cm shorter HT, P = 0.016. Marginal food security among women who were below median HT was associated with about 2.0 kg/m2 higher BMI, P = 0.042. %BF was not associated with FI among women.

CONCLUSIONS

FI is associated with shorter HT and lower %BF and BMI in men. Women's HT should be considered in the reported associations between FI and higher BMI.

Prevalence of obesity and abdominal obesity in the Lausanne population

BACKGROUND

Obesity can be defined using body mass index (BMI) or waist (abdominal obesity). Little information exists regarding its prevalence and determinants in Switzerland. Hence, we assessed the levels of obesity as defined by BMI or waist circumference in a Swiss population-based sample.

METHODS

Cross-sectional, population-based non-stratified random sample of 3,249 women and 2,937 men aged 35-75 years living in Lausanne, Switzerland. Overall participation rate was 41%.

RESULTS

In men, the prevalences of overweight (BMI > or =25 kg/m2) and obesity (BMI > or =30 kg/m2) were 45.5% and 16.9%, respectively, higher than in women (28.3% and 14.3%, respectively). The prevalence of abdominal obesity (waist > or =102 in men and > or =88 cm in women) was higher in women than in men (30.6% vs. 23.9%). Obesity and abdominal obesity increased with age and decreased with higher educational level in both genders. In women, the prevalence of obesity was lower among former and current smokers, whereas in men the prevalence of obesity was higher in former smokers but did not differ between current and never smokers. Multivariate analysis showed age to be positively related, and education and physical activity to be negatively related with obesity and abdominal obesity in both genders, whereas differential effects of smoking were found between genders.

CONCLUSION

The prevalence of abdominal obesity is higher than BMI-derived obesity in the Swiss population. Women presented with more abdominal obesity than men. The association between smoking and obesity levels appears to differ between genders.