Contributions of Incidence and Persistence to the Prevalence of Childhood Obesity during the Emerging Epidemic in Denmark

Background

Prevalence of obesity is the result of preceding incidence of newly developed obesity and persistence of obesity. We investigated whether increasing incidence and/or persistence during childhood drove the prevalence of childhood obesity during the emerging epidemic.

Methods

Height and weight were measured at ages 7 and 13 years in 192,992 Danish school children born 1930–1969. Trends in the incidence (proportion obese at 13 years among those not obese at 7 years) and persistence (proportion obese at 13 years among those obese at 7 years) across birth cohort periods (1930–41 with low stable prevalence of obesity, 1942–51 with increasing prevalence, 1952–69 with the higher, but stable prevalence) were investigated. Logistic regression was used to examine the associations between BMI at 7 years as a continuous trait, allowing interactions with the birth cohorts, and occurrence of obesity at 13 years.

Results

The prevalence of obesity was similar at 7 and 13 years and increased across birth cohorts in boys from around 0.1% to 0.5% and in girls from around 0.3% to 0.7%. The incidence of obesity between ages 7 and 13 years increased from 0.15% to 0.35% in boys and from 0.20% to 0.44% in girls. The persistence increased from 28.6% to 41.4% in boys and from 16.4% to 31.0% in girls. Despite a decrease over time, the remission of obesity occurred in >60% of obese children in the last birth cohort. However, the odds ratios of obesity at age 13 years in relation to the full range of BMI at 7 years remained unchanged across the birth cohort periods.

Conclusions/Significance

The development of the obesity epidemic in children was due to an increase in both incidence and persistence of obesity. Contrary to prevailing expectations, a large, although declining, proportion of children obese at an early age underwent remission during childhood.     

Climatic regime shifts and decadal-scale variability in calanoid copepod populations off southern California

Decadal‐scale climatic regimes and the shifts between them have important impacts on marine ecosystems. Climatic regime shifts have been observed or hypothesized in the North Pacific basin in 1976–77 and 1989. This paper examines long‐term (1951–99) trends in calanoid copepod populations off southern California, and the evidence for responses to regime shifts. Most of the species of calanoid copepod that were analysed underwent one or more step changes during the 49 years covered by the study. All but one of these changes occurred in five periods: the late 1950s, late 1960s, mid‐1970s, early 1980s and around 1990. The late 1960s changes are considered to be artifacts of an increase in sampling depth. Strong El Niño conditions affected California waters during the late 1950s and early 1980s. The step changes of the mid‐1970s and late 1980s to early 1990s may have been responses to regime shifts or other climatic events. 28% of the species and subspecies responded to the 1976–77 event, all increasing in abundance. Another 28% of the copepod categories underwent step changes around 1990, most decreasing. Evidence for regime shifts in the hydrographic variables that were examined is mixed. The 10‐m temperature increased in the mid‐1970s. Abrupt changes in variables around 1990 were short‐lived. However, the population responses around 1990 and to the El Niños of the late 1950s and early 1980s indicate that some species of calanoid copepods may respond on longer time scales to environmental conditions that persist only a few years.     

Secular trends in childhood obesity in Denmark during 50 years in relation to economic growth

Objective: Our aim was to examine whether secular trends in childhood overweight and obesity during five decades could be explained by economic growth. Research Methods and Procedures: Annual measurements of height and weight were available for all children born between 1930 and 1983 attending primary school in the Copenhagen Municipality: 165,389 boys and 163,609 girls from the age of 7 through 13 years. After computerization, we calculated BMI (kg/m²) and estimated the prevalence of overweight and obesity, according to international age‐ and gender‐specific criteria, by year of birth and of measurement, and separately by each age group and gender. Economic growth was indicated by the Gross National Product and the overall consumption per capita, adjusted for inflation. Results: The prevalence of overweight occurred in phases: an increase from 1930 until the 1950s, followed by a plateau period between the 1950s and the 1960s and a steep increase thereafter. This pattern was apparent across all age groups and in both genders. Obesity trends showed a similar phase pattern; the prevalence remained relatively stable from 1930 until the 1940s, increased until the mid‐1950s, followed by a plateau until 1965, and thereafter a second steep increase. Obesity trends were similar among boys across all age groups, although only among girls from 11 to 13 years of age. In both genders, increments were most pronounced in the upper BMI percentiles. After stagnation until 1947, the economic growth indicators showed a steady increase; i.e., after the first increase started in overweight and obesity, whether analyzed by year of birth or year of measurement, there were no indications of phases in the rise thereafter. Discussion: Prevalence of overweight and obesity among Danish children rose in phases, which were not paralleled by trends in economic growth. The macroeconomic growth indicators seem inappropriate as proxies for the environmental exposures that have elicited the obesity epidemic.     

Increase in the Prevalence of Obesity in Switzerland 1982–2007: Birth Cohort Analysis Puts Recent Slowdown into Perspective

Although the prevalence of obesity continues to increase in Switzerland, the latest figures suggest a slowdown in the rate of increase. In order to elucidate whether this could be the onset of a trend reversal, we analyzed cross‐sectional data by birth cohort. We assessed the prevalence of overweight+ (BMI ≥25 kg/m²) and obesity (BMI ≥30 kg/m²) in six population surveys with self‐reported height and weight values (Switzerland, N = 68,829, 1982–2007, men (45%) and women (55%), aged 20–84 years) by 10‐year birth cohorts (from the decade 1910–1919 through to 1970–1979). We found that increases in the prevalence of overweight+ and obesity occurred mainly in the cohort born 1930 to 1939, and again in the cohorts born 1960 to 1979. The accelerated increase in the prevalence of overweight+ in the youngest birth cohort and the lower prevalence in the oldest birth cohorts suggest that the current slowdown seen in Switzerland may not herald the onset of a trend reversal. As this example shows, simple comparisons of prevalence rates over time could provide a misleading picture of actual trends. Birth cohort analysis may offer a valuable alternative.     

Trends in overweight and obesity in Chinese adults: between 1991 and 1999-2000

Objective: The aim of this study was to evaluate trends in BMI and the prevalence of overweight (BMI ≥ 25 kg/m²) and obesity (BMI ≥ 30 kg/m²) between 1991 and 1999–2000 among Chinese adults. Methods and Procedures: In this study, two population‐based samples of Chinese adults aged between 45 and 79 years (n = 7,858 during each period), and comparable in the distributions of age, gender, degree of urbanization, and region (North/South) were used. Height and weight were measured using identical procedures at each period, and BMI was calculated as weight (in kilogram) divided by height (in square meter). Results: From 1991 to 1999–2000, the mean BMI increased from 21.8 to 23.4 kg/m² among men and from 21.8 to 23.5 kg/m² among women (each P < 0.001). Among men, the prevalence of overweight and obesity increased from 9.6 and 0.6%, respectively, in 1991 to 20.0 and 3.0%, respectively, in 1999–2000 (each P < 0.001). Among women, the prevalence of overweight and obesity increased from 14.5 and 1.8%, respectively, in 1991 to 26.5 and 5.2%, respectively, in 1999–2000 (each P < 0.001). The prevalence of overweight and obesity increased in all age groups, in rural and urban areas, and in North and South China, with greater relative increases in obesity among older age groups, South China, and rural areas (P interaction < 0.05). Discussion: Overweight and obesity increased tremendously during the 1990s in China. These data underscore the need for national programs in weight maintenance and reduction, to prevent obesity‐related outcomes in China.     

Monitoring the obesity epidemic in France: the Obepi surveys 1997-2006

The objective of the study was to describe the prevalences of obesity in French adults over a 9-year period. Mailed questionnaire surveys, in 1997, 2000, 2003, and 2006, sampled 20,000 representative French households by the method of quotas. Weight, height, and waist circumference were reported by all members of the selected households > or = 18-years. Obesity was defined according to the WHO criteria, BMI > 30 kg/m2. The prevalence of adult obesity increased progressively from 8.6% (95% confidence interval: 8.2-8.8) in 1997 to 13.1% (12.7-13.5) in 2006. The increase affected all ages, socioeconomic strata, and regions. Although the prevalence of obesity increased in parallel in men and women from 1997 to 2003, the rate of increase was lower in men between 2003 and 2006. These surveys showed a sharp increase in the prevalence of obesity in France in recent years contrasting with a stable prevalence in the 1980s. The results of the first Obepi surveys prompted the French government to implement a Nutrition and Health National Plan in 2001. Regular monitoring of obesity prevalence in France and neighboring countries is needed to compare future trends.     

Genetic associations with temporal shifts in obesity and severe obesity during the obesity epidemic in Norway: A longitudinal population-based cohort (the HUNT Study)

BackgroundObesity has tripled worldwide since 1975 as environments are becoming more obesogenic. Our study investigates how changes in population weight and obesity over time are associated with genetic predisposition in the context of an obesogenic environment over 6 decades and examines the robustness of the findings using sibling design.Methods and findingsA total of 67,110 individuals aged 13–80 years in the Nord-Trøndelag region of Norway participated with repeated standardized body mass index (BMI) measurements from 1966 to 2019 and were genotyped in a longitudinal population-based health study, the Trøndelag Health Study (the HUNT Study). Genotyping required survival to and participation in the HUNT Study in the 1990s or 2000s. Linear mixed models with observations nested within individuals were used to model the association between a genome-wide polygenic score (GPS) for BMI and BMI, while generalized estimating equations were used for obesity (BMI ≥ 30 kg/m²) and severe obesity (BMI ≥ 35 kg/m²).The increase in the average BMI and prevalence of obesity was steeper among the genetically predisposed. Among 35-year-old men, the prevalence of obesity for the least predisposed tenth increased from 0.9% (95% confidence interval [CI] 0.6% to 1.2%) to 6.5% (95% CI 5.0% to 8.0%), while the most predisposed tenth increased from 14.2% (95% CI 12.6% to 15.7%) to 39.6% (95% CI 36.1% to 43.0%). Equivalently for women of the same age, the prevalence of obesity for the least predisposed tenth increased from 1.1% (95% CI 0.7% to1.5%) to 7.6% (95% CI 6.0% to 9.2%), while the most predisposed tenth increased from 15.4% (95% CI 13.7% to 17.2%) to 42.0% (95% CI 38.7% to 45.4%). Thus, for 35-year-old men and women, respectively, the absolute change in the prevalence of obesity from 1966 to 2019 was 19.8 percentage points (95% CI 16.2 to 23.5, p < 0.0001) and 20.0 percentage points (95% CI 16.4 to 23.7, p < 0.0001) greater for the most predisposed tenth compared with the least predisposed tenth, defined using the GPS for BMI. The corresponding absolute changes in the prevalence of severe obesity for men and women, respectively, were 8.5 percentage points (95% CI 6.3 to 10.7, p < 0.0001) and 12.6 percentage points (95% CI 9.6 to 15.6, p < 0.0001) greater for the most predisposed tenth. The greater increase in BMI in genetically predisposed individuals over time was apparent after adjustment for family-level confounding using a sibling design. Key limitations include a slightly lower survival to date of genetic testing for the older cohorts and that we apply a contemporary genetic score to past time periods. Future research should validate our findings using a polygenic risk score constructed from historical data.ConclusionsIn the context of increasingly obesogenic changes in our environment over 6 decades, our findings reveal a growing inequality in the risk for obesity and severe obesity across GPS tenths. Our results suggest that while obesity is a partially heritable trait, it is still modifiable by environmental factors. While it may be possible to identify those most susceptible to environmental change, who thus have the most to gain from preventive measures, efforts to reverse the obesogenic environment will benefit the whole population and help resolve the obesity epidemic.

In a longitudinal population-based cohort study in Norway, Maria Brandkvist and colleagues investigate how genetic predisposition relates to changes in BMI and obesity over the past six decades.     

Gender‐ethnic Disparity in BMI and Waist Circumference Distribution Shifts in US Adults

While obesity has been increasing in the United States, little is known about the variation in recent BMI and waist circumference (WC) distribution shifts across socio‐demographic groups. We assessed shifts in BMI and WC distributions and compared between‐group differences over the past decade, and projected future BMI and WC distributions and prevalence of obesity and central obesity using National Health and Nutrition Examination Survey (NHANES) 1988–1994 and 1999–2004 data. BMI/WC distributional shifts overall and in percentiles were compared across groups. Average yearly shift was calculated and used for projecting future distributions and prevalence. Both BMI and WC increased more in their uppermost percentile distribution, though BMI shift declined toward the uppermost percentiles among women. Heavier Americans gained more adiposity over the past decade. Ethnic (non‐Hispanic (NH) white vs. black) disparities in mean BMI and WC became wider. Over the survey period, mean BMI increased by 1.3 units vs. 1.8 units among men and women, whereas WC, by 4.2 cm vs. 4.8 cm. Young adults had the largest increase. Shift in women's WC was stable between the 25th and 75th percentiles, but gained pace at higher WC, while women's BMI and men's BMI and WC shifts increased linearly. NH black women had the largest shifts and would have central obesity and obesity prevalence of 90.8 and 70.7% by 2020. Shifts in BMI and WC distribution varied across age‐, gender‐, and ethnic groups. Future rise in the obesity and central obesity prevalence rates are expected, but would vary by demographic groups.     

Comparison of BMI and percentage of body fat of Indian and German children and adolescents

Today, serious health problems as overweight and obesity are not just constricted to the developed world, but also increase in the developing countries (Prentice 2006, Ramachandram et al. 2002). Focusing on this issue, BMI and percentage of body fat were compared in 2094 schoolchildren from two cross-sectional studies from India and Germany investigated in 2008 and 2009. The German children are in all age groups significantly taller, whereas the Indian children show higher values in BMI (e.g. 12 years: Indian: around 22 kg/m2; German: around 19 kg/m2) and in the percentage of body fat (e.g. 12 years: Indian: around 27%; German: around 18-20%) in most of the investigated age groups. The Indian children have significantly higher BMI between 10 and 13 (boys) respectively 14 years (girls). Indian children showed significant higher percentage of body fat between 10 and 15 years (boys) and between 8 and 16 years (girls). The difference in overweight between Indian and German children was strongest at 11 (boys) and 12 (girls) years: 70% of the Indian but 20% of the German children were classified as overweight. In countries such as India that undergo nutritional transition, a rapid increase in obesity and overweight is observed. In contrast to the industrialized countries, the risk of overweight in developing countries is associated with high socioeconomic status. Other reasons of the rapid increase of overweight in the developing countries caused by different environmental or genetic factors are discussed.     

Evolution of the Prevalence of Obesity in the Workers of a General Hospital in Mexico

Objective: The objective of this study was to compare the prevalence of overweight and obesity in the first Prevalencia de factores de nesso cardiovascular en Trabajadores survey (1994) with the prevalence of overweight and obesity observed in the second survey (1996). Research Methods and Procedures: For both surveys the following individual data were collected: age, sex, weight, height, and body mass index (BMI). The 1994 survey included 2383 people and the 1996 survey included 2759 people. The degree of BMI was classified according to the current World Health Organization definitions. The population was divided by gender and age group, and the prevalence of each level of overweight was calculated. Additionally, the prevalence of different cutoff levels of BMI was calculated by gender and age groups. Results: The global prevalence of age‐adjusted overweight increased from 26.91% to 37.45%. This increase was observed in both genders but the men had a higher increase from 24.51% to 40.21%. Overweight was more frequent in men than in women in all age groups. Male overweight prevalence was higher in the 40‐ to 59‐year‐old group and ≥60‐year‐old group. Female overweight prevalence was predominant in the 30‐ to 39‐year‐old, 40‐ to 49‐year‐old, and 50‐ to 59‐year‐old groups. Global prevalence of obesity (≥30 kg/m²) changed from 13.8% to 17.2%. Particularly, global prevalence of obesity class I increased from 9.66% to 12.6%; in men this figure increased from 9.04% to 13.05% and in women from 9.9% to 12.71%. Discussion: Prevalence of overweight and obesity has increased significantly in the studied population. It is necessary to implement lifestyle modifications to prevent the increase of prevalence of overweight and obesity.     

Spatial and geographic characteristics of marriage migration in the Lugansk population

Data from the Lugansk City Registry Office archives of 1960, 1985, 1990, and 2000 were used to calculate genetic demographic parameters characterizing marriage migration. The migration coefficients (m) in these years were 0.69, 0.54, 0.47, and 0.36; the endogamy indices were 12.1, 24.4, 30.5, and 43.2%, and the marriage contingency coefficients with respect to birthplace (K) were 0.12, 0.10, 0.11, and 0.13, respectively. The mean migration distance increased by a factor of 1.5 (from 599 to 870 km), and the mean parent-offspring distance decreased by a factor of 1.3 (from 415 to 317 km) during the period between 1960 and 2000. The mean marriage distance increased from 654 to 718 km between 1960 and 1985 and then decreased to 594 km by the year 2000. The proportion of "long-distance" migrations calculated using Malecot's model increased from 0.013 to 0.021 between 1960 and 1990 and decreased to 0.005 by 2000. The proportion of "short-distance" migrations was 0.77 in 1960 and 0.51 in 2000. The migration efficiency increased from 0.09 to 0.18 between 1960 and 1990 and decreased to 0.07 by 2000. In the years studied, the indices of isolation by distance (b) were 0.0005, 0.0004, 0.0005, and 0.0002, and the population "radii" were 90, 118, 119, and 168 km, respectively.     

Changes in wood and foliar δ13C in sugar maple at Gatineau Park,Quebec, Canada

Leaf samples and tree rings formed between the mid‐1960s and mid‐1990s from sugar maple (Acer saccharum Marsh.) at Gatineau Park (45°30′ N, 75°54′ W), Quebec were analysed for δ¹³C. Leaf samples were collected at ground level (1–2 m above ground) at monthly intervals during the summer, whereas tree cores were extracted from the largest trees (d.b.h. > 30 cm) in the young deciduous forest in August 1998. Significant linear decreases in δ¹³C over time were found in foliage and tree rings, but the decrease in δ¹³C was significantly greater in foliage than in the wood. The apparent isotopic discrimination (Δ) of tree rings varied insignificantly around a mean of 18‰, whereas foliar Δ increased significantly from 19‰ in the 1960s to around 23‰ by the mid 1990s, likely as a result of an increasing canopy effect as the forest matured. Using models of carbon discrimination and Δ‐values of the tree rings, we calculate that the intrinsic water use efficiency of mature sugar maple has increased by approximately 4% over the study period.     

Dynamics of the genetic demographic structure of the Kursk province population: migration processes

Marriage records from parish books of the second half of the 19th century and marriage records of 1967-1970 and 1993-1995 obtained from registry offices were used to analyze the dynamics of genetically significant parameters of migration and marriage structure with respect to spouses' birthplaces in populations of different hierarchical levels in the Kursk oblast. It was found that, among the persons contracting marriage (both males and females), the proportions of those who were born in the same population and those who were born in any population of the Kursk oblast decreased by about one third and one fifth, respectively, for the 130-year period. In rural and small urban populations, the coefficients of marriage migration in the 19th century were an order of magnitude lower than in the 20th century. The immigration to urban populations was maximum in the late 1960s (m = 0.745 in small towns and m = 0.680 in Kursk), and that to rural populations, in the 1990s (m = 0.344). In both urban and rural populations, the mean distance between the spouses' birthplaces has increased by several times for the period studied. The endogamy level has decreased approximately twofold: from 0.797 to 0.380 in Kursk, from 0.897 to 0.419 in small towns, and from 0.958 to 0.440 in rural districts. The marriage assortativeness with respect to birthplace was maximum in the late 19th century (K = 0.393-0.491) and minimum in the 1960s (K = 0.155-0.246). The increase in genetic diversity of the urban population of the Kursk oblast due to migration has been slowing down since the late 20th century, whereas the outbreeding level is still increasing in rural populations.     

Obesity among People with and without Mental Retardation across Adulthood

Objective: This study was designed to explore obesity during adulthood and the likelihood of moving out of obesity among 1809 adults without disability and 680 adults with mental retardation who received care at the same primary care practices during the period of 1990 to 2003. Research Method and Procedures: A retrospective observational design using medical records first identified patients with mental retardation (MR) and age‐matched controls without disabilities. Data on BMI collected during each primary care visit allowed exploration of obesity at three levels. Moving out of obesity was defined as having a BMI <25 kg/m². We also abstracted data on age, sex, race, and other medical conditions. Results: For adults 20 to 29 years of age, 33.1% of patients without disability and 21% of patients with MR had a BMI >30 kg/m². Between the ages of 50 and 59 years, 40.5% of the patients without disability and 35.2% of the patients with MR had a BMI >30 kg/m². Patients with mild MR had similar prevalence rates of obesity and patients with severe MR had significantly lower prevalence of obesity compared with the patients without disability through 50 years of age. Throughout the period from 20 to 60 years of age, between 15% and 40% of individuals with and without MR, who were previously obese, were not currently obese. Discussion: Throughout the adult years, an increasing proportion of individuals with and without MR are obese. However, obesity is not a chronic state; many people transition back to a normal body weight.     

Distribution of Anthropometric Variables and the Prevalence of Obesity in Populations of West African Origin: The International Collaborative Study on Hypertension in Blacks (ICSHIB)

A survey of the prevalence of hypertension and associated risk factors including obesity was carried out among persons of West African heritage currently living in societies at different stages of social, economic and technological development. We present here the distribution of several anthropometric variables and the prevalence of obesity in these populations. Using a standard protocol with centralized training of field staff, 7 439 men and women aged 24 to 75 from six multinational sites were recruited and examined. Although men were taller, women were more obese across sites. Body mass index (BMI) and consequently the prevalence of overweight and obesity increased with westernization from rural African subsistence farming communities to suburban Chicago. Average BMI increased with age until about age 54, and then began to decline or at least level off. The mean BMI for African-American men and women was 27.1 kg/m² and 30.8 kg/m², respectively. Men displayed high levels of centripetal fatness, measured as the waist-to-hip ratio (WHR), compared to the women across site. Based on the US Department of Agriculture guidelines, 22.6% and 56.9% of the African-American men and women had elevated WHR. Although account must be taken of the important contribution of an individual's genetic background, this multinational study of persons with similar heritage clearly shows the potent impact of current environmental factors on the distribution and level of obesity.     

The Canadian Obesity Epidemic: An Historical Perspective

Objective: To examine temporal trends in stature, body mass, body mass index (BMI), and the prevalence of overweight and obesity in Canada. Research Methods and Procedures: Data for adults 20 to 64 years of age were compared across eight Canadian surveys conducted between 1953 and 1998. Temporal trends in stature and body mass were examined using regression, and changes in weight‐for‐height were expressed as changes from 1953. BMI data were available from 1970 to 1972 to examine changes in overweight and obesity. Qualitative changes in the BMI distribution were examined using Tukey mean‐difference plots. Results: Significant temporal trends in stature and body mass have occurred since 1953 in Canada. Median stature increased 1.4 cm/decade in men and 1.1 cm/decade in women, whereas median body mass increased 1.9 kg/decade in men and 0.8 kg/decade in women. Increases in the 75th percentile of body mass were larger than the median. The average weight‐for‐height increased 5.1% in men and 4.9% in women from 1953. Furthermore, the prevalences of overweight and obesity have increased from 40.0% and 9.7% in 1970–1972 to 50.7% and 14.9% in 1998, respectively. The entire BMI distribution has shifted to the right since 1970–1972 and has become more skewed to the right for men than for women. Discussion: There have been significant increases in stature and body mass in Canada over the last 45 years. Body mass has increased more than stature, particularly in the upper percentiles, which has resulted in the currently observed high prevalences of overweight and obesity.     

High body mass alters colonic sensory-motor function and transit in humans

There is increased prevalence of abdominal pain and diarrhea and decreased gastric sensation with increased body mass index (BMI). Our hypothesis is that increased BMI is associated with increased colonic motility and sensation. The study aim was to assess effect of BMI on colonic sensory and motor functions and transit. We used a database of colonic tone, compliance, and perception of distensions measured by intracolonic, barostat-controlled balloon, and gastrointestinal transit was measured by validated scintigraphy in healthy obese and nonobese subjects. Regression analysis was applied to assess the association of BMI with colonic sensory and motor functions. We included adjustments for sex differences, age, height, balloon volumes during distension, and psychological stress. Among 165 participants (87 women, 78 men), increased BMI was associated with decreased colonic compliance (P < 0.006, adjusted), decreased pain rating during distensions (P = 0.02, adjusted), and a higher threshold for pain (P = 0.042, adjusted). Sensation for gas, colonic tone, and contraction after meal ingestion were not significantly associated with BMI. Transit was assessed in 72 participants (41 women, 31 men); colonic transit was faster with BMI >30 kg/m(2) (P = 0.003 unadjusted, P = 0.08 adjusted for gender). In conclusion, BMI >25 kg/m(2) is associated with decreased colonic compliance and pain sensation; colonic transit is accelerated particularly with BMI >30 kg/m(2) in women. These data suggest that colonic dysfunction may contribute to diarrhea, but the cause of increased abdominal pain in obesity is not explained by the studies of colonic sensation and requires further study of afferent, spinal, and central mechanisms.     

Varying patterns of BMI increase in sex and birth cohorts of Korean adults

Objective: The Korean population has recently experienced a rapid increase in obesity associated with lifestyle changes arising from economic growth. We examined trends in BMI by analyzing sex‐specific birth cohorts using 3,400,727 measurements from 1,662,477 Korean adults. Research Methods and Procedures: Birth cohort data were collected from the employees of government organizations and schools and their dependents, 20 to 65 years of age, who participated in health examinations provided by the Korean National Health Insurance Corporation in 1992, 1996, and 2000. Results: The prevalence of obesity (BMI ≥ 30 kg/m²) was 0.8% among men and 0.3% among women in 1992, but by 2000, it had increased 2.5‐fold to 2.0% in men and 2.3‐fold to 0.7% in women. Over the 8‐year period, the mean BMI increased 0.8 kg/m² in men and 0.3 kg/m² in women. The rate of BMI increase over the 8 years varied markedly among the sex‐specific birth cohorts, with the steepest slopes representing the youngest men (0.2 kg/m² per year). Discussion: National health promotion activities should target younger men to prevent an increase in obesity‐related morbidity and mortality.     

Trends in the Prevalence of Overweight and Obesity among Chinese Preschool Children from 2006 to 2014

Objective

To examine the trends in the prevalence of overweight and obesity among preschool children from 2006 to 2014.

Methods

A total of 145,078 children aged 3–6 years from 46 kindergartens finished the annual health examination in Tianjin, China. Height, weight and other information were obtained using standardized methods. Z-scores for weight, height, and BMI were calculated based on the standards for the World Health Organization (WHO) child growth standards.

Results

From 2006 to 2014, mean values of height z-scores significantly increased from 0.34 to 0.54, mean values of weight z-scores kept constant, and mean values of BMI z-scores significantly decreased from 0.40 to 0.23. Mean values of height z-scores, weight z-scores, and BMI z-scores slightly decreased among children from 3 to 4 years old, and then increased among children from 4 to 6 years old. Between 2006 and 2014, there were no significant changes in prevalence of overweight (BMI z-scores >2 SD) and obesity (BMI z-scores >3 SD) among 3–4 years children. However, prevalence of obesity (BMI z-scores >2 SD) increased from 8.8% in 2006 to 10.1% in 2010, and then kept stable until 2014 among 5–6 years children. Boys had higher prevalence of obesity than girls.

Conclusions

Mean values of BMI z-scores decreased from 2006 to 2014 among Chinese children aged 3–6 years old due to the significant increase of height z-scores. Prevalence of obesity increased from 2006 to 2010, and then kept stable until 2014 among children aged 5–6 years. The prevalence of obesity was higher in boys than in girls.