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Body height is associated with environmental conditions. It has been suggested that under poor conditions when inequality within a population increases, also the variability in height tends to increase. We studied the association of body height, within-country variability in height and geographic and historic origin in 767 growth studies carried out in 80 countries, published between 1794 and 2013, with data on N = 78,184 infants age 2 years, and N = 2,130,729 juveniles age 7 years. The studies represent almost the whole spectrum of economic diversity in human societies since the end-18(th) century. 207 studies contained data for both infants and juveniles with 50,819 subjects (age 2), and 123,078 subjects (age 7). Multiple linear regressions showed significant interactions between height, sex, historic year of the study, geographic origin, and within-study standard deviation for height with multiple R-squared = 0.527, p < 0.001, at age 2, and multiple R-squared = 0.436, p < 0.001, at age 7. Yet, the two age groups differed in respect to within-study standard deviation for height. We found a significant association between body height and within-study standard deviation for height only at age 2: tall infant populations are less variable in height (r = -0.27, p < 0.01). There was no such association in children aged 7 years. Tall children from affluent and short children from less affluent countries do not differ in the variability of body height. The data suggest that the 'environmental adversity' hypothesis for variation in growth: small mean values for height go along with large standard deviations for height, does not apply for children at age 7.

Summary: The aim of this study was to assess changes in prevalence of overweight and obesity among children born in 1996 and 1990 in Vilnius city. The results were based on comparison of two longitudinal data sets (N = 624 and N = 389) collected from the personal health records of children born in 1996 and 1990 respectively. No statistically significant differences in final height and BMI were established between children born in 1990 and 1996; however, both boys and girls born in 1996 appeared to be higher and heavier at different ages compared to their peers born in 1990. After controlling for tempo, the differences in height between the two cohorts have become insignificant for girls, with exceptions at the age of 3 and 10 years; for boys, the differences between the cohorts have remained significant, however at a slightly lower level. More children born in 1996 tended to be overweight and obese. In six years, the prevalence of overweight in Vilnius children has more than doubled; the prevalence of obesity has increased up to five times in some age groups.

Background: Human populations differ in height. Recent evidence suggests that social networks play an important role in the regulation of adolescent growth and adult height. We further investigated the effect of physical connectedness on height., Material and Methods: We considered Switzerland as a geographic network with 169 nodes (district capitals) and 335 edges (connecting roads) and studied effects of connectedness on height in Swiss conscript from 1884 - 1891, 1908 - 1910, and 2004 - 2009. We also created exponential-family random graph models to separate possible unspecific effects of geographic vicinity., Results: In 1884 - 1891, in 1908 - 1910, and in 2004 - 2009, 1(st), 2(nd) and 3(rd) order neighboring districts significantly correlate in height (p < 0.01). The correlations depend on the order of connectedness, they decline with increasing distance. Short stature districts tend to have short, tall stature districts tend to have tall neighbors. Random network analyses suggest direct road effects on height. Whereas in 1884 - 1891, direct road effects were only visible between 1(st) order neighbors, direct road effects extended to 2(nd) and 3(rd) in 1908 - 1910, and in 2004 - 2009, also to 4(th) order neighbors, and might reflect historic improvements in transportation. The spatial correlations did not significantly change when height was controlled for goiter (1884 - 1889) and for median per capita income (2006), suggesting direct road effects also in goiter-allowed-for height and income-allowed-for height., Conclusion: Height in a district depends on height of physically connected neighboring districts. The association decreases with increasing distance in the net. The present data suggest that people can be short because their neighbors are short; or tall because their neighbors are tall (community effect on growth). Psycho-biological effects seem to control growth and development within communities that go far beyond our current understanding of growth regulation.