Stature and long-term labor market outcomes: Evidence using Mendelian randomization

We use the Young Finns Study (N = ∼2000) on the measured height linked to register-based long-term labor market outcomes. The data contain six age cohorts (ages 3, 6, 9, 12, 15 and 18, in 1980) with the average age of 31.7, in 2001, and with the female share of 54.7. We find that taller people earn higher earnings according to the ordinary least squares (OLS) estimation. The OLS models show that 10 cm of extra height is associated with 13% higher earnings. We use Mendelian randomization, with the genetic score as an instrumental variable (IV) for height to account for potential confounders that are related to socioeconomic background, early life conditions and parental investments, which are otherwise very difficult to fully account for when using covariates in observational studies. The IV point estimate is much lower and not statistically significant, suggesting that the OLS estimation provides an upward biased estimate for the height premium. Our results show the potential value of using genetic information to gain new insights into the determinants of long-term labor market success.     

A head above the rest: Height and adolescent psychological well-being

Using data from the National Longitudinal Study of Adolescent Health, we examine the effect of adolescent height on mental health as measured by Center for Epidemiological Studies Depression (CES-D) scores and Rosenberg Self-Esteem (RSE) scores. We find evidence that height is associated with fewer symptoms of depression among females 17–19 years of age, and among males 12–19 years of age. The negative relationship between height and depression among males persists after controlling for body mass index (BMI), differences in pubertal timing, and individual fixed effects, but does not explain the effect of height on educational attainment. We conclude that there is a small psychological benefit for males to being taller as an adolescent.     

广东黑石顶森林群落黄果厚壳桂(Cryptocaryaconcinna)幼苗的年龄结构和高度结构

黄果厚壳桂幼苗未有准确对应于年龄的外部特征,通过对相应样地中幼苗的解析,得出了以幼苗高度和基径对年龄的二元线性回归相对准确地划分幼苗年龄的方法,它优于单纯采用高度级或基径级划分年龄结构的方法,这种方法为非毁坏性的研究现存幼苗的年龄结构提供了依据。1993年起开始对黑石顶森林群落中黄果厚壳桂种群幼苗的年龄结构和高度结构进行了定位观测研究。黑石顶黄果厚壳桂幼苗的年龄结构以2龄和3龄幼苗占优势,幼苗的年龄结构表现出一定的年度波动性,其中由3龄到4龄幼苗多度大幅度地下降。将幼苗以每10cm为一级划分高度级发现黑石顶黄果厚壳桂幼苗中有一个以高度为10—30cm幼苗占明显优势的幼苗库,这个幼苗库主要由2—4龄幼苗组成。     

Height, wealth, and health: An overview with new data from three longitudinal studies

This overview, based on a literature review and new data from the three cohorts (Whitehall Studies I and II, and the Vietnam Experience Study), has four objectives: (a) to outline the major determinants of height, so providing an indication as to what exposures this characteristic may capture; (b) to summarise, by reviewing reports from large scale studies, the relation between adult height and a range of disease outcomes – both somatic and psychiatric – with particular emphasis on coronary heart disease (CHD) and stroke; (c) to discuss why these relationships may exist, in particular, the role, if any, of socioeconomic position in explaining the apparent associations; and, finally (d) to outline future research directions in this field.The large majority of evidence for predictors of height, and its health consequences, comes from observational studies. While genetic predisposition is a major determinant of height, secular rises in childhood and adult stature across successive birth cohorts suggest that early life environment also has an important impact. Plausible non-genetic determinants of height include nutrition, illness, socioeconomic status, and psychosocial stress. Evidence for an association between height and a series of health endpoints is accumulating. Thus, shorter people appear to experience increased risk of CHD, and these associations appear to be independent of socioeconomic position and other potentially confounding variables. For stroke, and its sub-types, findings are less clear. In contrast to CHD, some cancers, such as carcinoma of the colorectum, prostate, breast (in women), central nervous system, skin, endometrium, thyroid and blood (haematopoietic) are more common in taller people. While height may be negatively related to the risk of completed suicide, conclusions about the links between stature and other health endpoints is problematic given the paucity of evidence, which should be addressed.Ultimately, for want of better data, investigators in this area have used height as a proxy for a range of pre-adult exposures. In future, research should aim to explore the predictive capacity of direct measures of diet, psychosocial stress, childhood chronic illness and so on, rather than focus on height or its components. The problem is that extended follow-up of child cohorts with such data are required, and studies which hold these data are not currently available, although several are either maturing to the point where they offer sufficient clinical outcomes to facilitate analyses or are in the advanced planning stage.     

Do American born Japanese children still grow faster than native Japanese?

Growth patterns of Japanese schoolchildren in Hawaii, composed of 2,954 boys and 3,213 girls aged between 11 and 17, were compared with those comparable groups of Japanese schoolchildren in Japan based on the data published by the Japanese Ministry of Education. Growth characteristics studied were height, weight, and relative weight index, weight/(height). The Hawaii-Japanese boys were taller at early ages but the difference disappeared by age 16. Native Japanese girls were shorter than Hawaii-Japanese until age 13, but they overtook the latter by age 14, exceeding them in height after age 15. A similar pattern was found in weights of girls but the Hawaii-Japanese boys remained consistently heavier by 5.0 to 9.0 kg than native Japanese. The relative weight measure indicated that the Hawaii boys were more "obese" than native Japanese boys for the growth period studied; whereas the same tendency was maintained until age 15 in girls. These observations indicate a marked degree of convergence of the patterns of physical growth of the two populations, whose differences were unmistakably in favor of American born children in earlier studies. It is concluded that the convergence is due largely to the improved environmental conditions in Japan in recent years.     

A tradeoff between reproduction and growth in contemporary Finnish women

Women have been suggested to trade growth in height for reproduction, as an earlier age at menarche and first birth seem to be related to shorter adult stature. Although women likely accrue fitness benefits by maturing and starting reproduction at young age, short adult stature may be selected against by natural and sexual selection later in their life. We studied how age at menarche and first reproduction affected adult height and whether adult height in turn was related to lifetime reproductive success in Finnish women born 1946–1958. Our results show that a delay of 1 year in age at menarche and first reproduction was related to a 0.43- and 0.20-cm increase in adult height, respectively. The sex of the first-born offspring was not related to adult height. Moreover, women gained fitness benefits by starting reproduction early but not by growing tall. These findings among Finnish women are thus compatible with tradeoffs between reproduction and growth, by showing a compromised adult height at the cost of early age at menarche and first birth. However, in these women, natural selection favored those women who traded their stature for young motherhood.     

What is driving the relationship between height and cognition? Evidence from the Twins Early Development Study

Taller children tend to have better cognitive ability, and the relationship between height and cognition has been proposed as an explanation for the height-wage labor market premium. Height-cognition associations may arise due to social factors that favor taller individuals or be driven by “common factors” that are correlated with height and cognition. Indeed, there is now evidence of a genetic correlation between height and cognition that provides specific evidence for this concern. We examine whether genetic factors explain the relationship by estimating associations between childhood height and cognition in the Twins Early Development Study. We find that height is associated with better cognition even after controlling for genetic and environmental factors shared by twins. The association between height and cognition within fraternal twin pairs is also robust to controlling for individual genetic predictors of height and cognition. These results suggest that genetic factors are not solely responsible for driving the relationship between height and cognition.     

儿童身高生长追踪研究

以北京市106名儿童为样本 ,为研究各年龄生长速度的集中趋势、变异状况以及与生长速度有关的参数 ,追踪观察这些儿童自6、7岁至 18岁时共12年的身高变化 ,并做有关参数分析。报告了各年龄组身高生长速度的均值及标准差 ,该组儿童身高生长突增开始年龄 (男10.73±1 .12岁 ,女 9.00± 1.18岁 )及速度 (男4.51± 0.65cm/年 ,女 4.95± 0.79cm/年 ) ;身高生长高峰发生年龄 (男 1 3.0 7±1.08岁 ,女11.32± 1.32岁 )及速度高峰值 (男10 .01± 1.59cm/年 ,女8.13± 1.03cm/年 ) ;以及生长突增结束年龄 (男16.18± 1.02岁 ,女 13.96± 1.09岁 )。分析了最终身高与生长突增有关指标的相关关系。     

Estimation of total water and fatness from weight and height: inaccurate for lean women

Mellits and Cheek have provided a regression equation which predicts total water, and by extension, fat, from weight and height of women. The equation has been used by many researchers as a convenient means to estimate fat when more complicated body composition estimation techniques are not possible. It is an essential component of evidence provide by Frisch for the critical fat hypothesis. The equation has not been validated on another sample, however, and has a large standard error. I test the Mellits and Cheek equation on five samples of young women, two of which show a normal range of heights and weights. The other three are athletic samples composed of lean women. In the normal samples mean fat percent determined by density (from underwater weighing) is closely approximated by the weight and height equation but not in the lean samples. When measured fat is regressed on estimated fat, correlations are low, and standard errors are high, suggesting that the Mellits and Cheek equation predicts poorly the body fat percentage of individual females. In summary, the Mellits and Cheek equation is moderately useful for the prediction of group means for body composition on samples with normal ranges of height and weight. It does not produce acceptable results on groups selected for extreme leanness or obesity. It is not recommended for fat prediction of individuals.     

Are chronic diseases related to height? Results from the Portuguese National Health Interview Survey

This paper analyze the association between height and chronic diseases in Portugal and the extent to which this relationship is mediated by education. The sample upon which the analysis is based comprised those participants in the 2005/2006 Portuguese National Health Interview Survey (n = 28,433) aged 25–79. Logistic regressions measured the association of height with ten chronic diseases, adjusting for age, lifestyle, education, and other socioeconomic factors. Among women, an additional centimeter in stature significantly decreased the prevalence of asthma, chronic pain, and acute cardiac disease, by 0.057, 0.221, and 0.033 percentage points, respectively. Also, mental disorders were significantly less prevalent in the last quartile of height. Among men, an additional centimeter in height was associated with a 0.074 lower prevalence of asthma, and men in the last quartile of height were significantly less at risk of acute cardiovascular disease. There was no significant association between height and the risk of diabetes, high blood pressure, cancer, and pulmonary diseases. As for the impact of education, women with a tertiary level were on average 5.3 cm taller than those with no schooling; among men, the difference was almost 9 cm. Adjusting for education reduced the height-related excess risk of ill health by 36% on average among men, and by 7% among women. The analysis indicates that there is a significant association of height with several chronic conditions, and that education plays a mediating role in the height–health connection. By emphasizing the role of height and education as determinants of chronic conditions, this paper also highlights the role of conditions related to childhood health and socioeconomic background.     

Secular trend in height in Al Ain-United Arab Emirates

Correlation between cycles in human stature and those in economic variables is well established. A recent review of international trends in this area provided information from most parts of the world but none on Arabs in the Middle East or more specifically the gulf region.The United Arab Emirates experienced a transformation in economic and social life followed the discovery of oil in the late 1960s and the wealth that it generated. No data is available on human growth at this period of time because its population never had health services prior to the 1970s. A study on conventional cardiovascular risk factors in 2004-2005 included 817 randomly selected national adults (≥18 years) from both genders. The relationship between height and age in this study showed both men and women have increased in height with time demonstrating the secular change in height most likely a result of changing socioeconomic factors.     

Body height,weight, and skeletal maturation in Hottentot (Khoikhoi) children

Growth of body height and weight and skeletal maturation are discussed, based on 49 male and 61 female Hottentot children aged 3 to 17 years from Warmbad, Namibia (South West Africa) and 124 boys and 113 girls aged 1 to 21 years of related populations, the Rehoboth Basters of Namibia and Cape Coloreds from Cape Town, South Africa. The related populations are taller and heavier than the Hottentots, and have almost the same body height as American blacks and whites at least after the age of 18 years. In the Hottentots and Rehoboth Basters, the mean TW2 skeletal age is always less than the British standard by one or two years in both sexes. In general, the Rehoboth Basters have a skeletal age that is intermediate between Hottentot and British children. In both Hottentots and Rehoboth Basters, the increase in body height shows a linear relation to the skeletal age, and the regression curves are almost parallel in both sexes. The differences in body height and weight between the Hottentots and Rehoboth Basters become greater after the skeletal ages of 15 years for boys and 13 years for girls.     

Child height and intergenerational transmission of health: Evidence from ethnic Indians in England

A large literature documents a widespread prevalence of small stature among Indian children as well as adults. We show that a height gap relative to a richer population such as whites in England also exists, although substantially reduced, among adult immigrants of Indian ethnicity in England. This is despite positive height selection into migration, demonstrated by ethnic Indian adults in England being on average 6–7 cm taller than in India. However, the difference between natives and ethnic Indians in England disappears among their younger sons and daughters, although it re-appears among adolescents. We estimate that, conditional on age, gender and parental height, ethnic Indian children of age 2–4 in England are 6–8% taller than in India. Such degree of catch up in one generation is remarkable, also because in England children of ethnic Indians have much smaller birthweight than whites, by about 0.4 kg on average.     

Heterogeneity in predictive power of early childhood nutritional indicators for mid-childhood outcomes: Evidence from Vietnam

We utilize longitudinal data on nearly 1800 children in Vietnam to study the predictive power of alternative measures of early childhood undernutrition for outcomes at age eight years: weight-for-age (WAZ8), height-for-age (HAZ8), and education (reading, math and receptive vocabulary). We apply two-stage procedures to derive unpredicted weight gain and height growth in the first year of life. Our estimates show that a standard deviation (SD) increase in birth weight is associated with an increase of 0.14 (standard error [SE]: 0.03) in WAZ8 and 0.12 (SE: 0.02) in HAZ8. These are significantly lower than the corresponding figures for a SD increase in unpredicted weight gain: 0.51 (SE: 0.02) and 0.33 (SE: 0.02).The heterogeneity of the predictive power of early childhood nutrition indicators for mid-childhood outcomes reflects both life-cycle considerations (prenatal versus postnatal) and the choice of anthropometric measure (height versus weight). Even though all the nutritional indicators that involve postnatal nutritional status are important predictors for all the mid-childhood outcomes, there are some important differences between the indicators on weight and height. The magnitude of associations with the outcomes is one aspect of the heterogeneity. More importantly there is a component of height-for-age z-score (at age 12 months) that adds predictive power for all the mid-childhood outcomes beyond that of birth weight and weight gain in the first year of life.     

Nonlinear growth generates age changes in the moments of the frequency distribution: the example of height in puberty

Higher moments of the frequency distribution of child height and weight change with age, particularly during puberty, though why is not known. Our aims were to confirm that height skewness and kurtosis change with age during puberty, to devise a model to explain why, and to test the model by analyzing the data longitudinally. Heights of 3245 Christ's Hospital School boys born during 1927-1956 were measured twice termly from 9 to 20 years (n=129508). Treating the data as independent, the mean, standard deviation (SD), skewness, and kurtosis were calculated in 40 age groups and plotted as functions of age t. The data were also analyzed longitudinally using the nonlinear random-effects growth model H(t)=h(t-epsilon )+alpha, with H(t) the cross-sectional data, h(t) the individual mean curve, and epsilon and alpha subject-specific random effects reflecting variability in age and height at peak height velocity (PHV). Mean height increased monotonically with age, while the SD, skewness, and kurtosis changed cyclically with, respectively, 1, 2, and 3 turning points. Surprisingly, their age curves corresponded closely in shape to the first, second, and third derivatives of the mean height curve. The growth model expanded as a Taylor series in epsilon predicted such a pattern, and the longitudinal analysis showed that adjusting for age at PHV on a multiplicative scale largely removed the trends in the higher moments. A nonlinear growth process where subjects grow at different rates, such as in puberty, generates cyclical changes in the higher moments of the frequency distribution.     

Height and weight growth patterns of school age deaf children

Distance and velocity curves for height and weight were analyzed in a mixed longitudinal sample of American White, American Negro and Mexican-American deaf children 6 through 17 years of age. The heights of deaf boys and girls are, on the average, consistently below an accepted pediatric standard from six through ten years of age. Between 11 and 17 years, deaf White and Negro boys approximate the standard, while White and Negro girls are at or slightly below the standard. Deaf Mexican-American children are consistently below the height standard. For body weight, deaf boys are at or slightly below the standard from 6 to 11 years, and are at or slightly above the weight standard from 12 to 17 years of age. White and Negro deaf girls generally approximate the weight standard from eight years of age on. Mexican-American deaf girls are consistently below the standard until 13 years of age, while between 14 and 17 years they are at or above the standard. Height and weight velocity curves for deaf children parallel closely the incremental standards of Falkner ('62). The height velocity curve, however, appears to peak, on the average, about one year earlier in deaf children.     

Standards of arm muscle by stature for the assessment of nutritional status of children

This study is based on a sample of 9,134 children ranging in age from 2 to 17 years from which the excessively lean and fat children by skinfold thickness were excluded. This sample was derived from the combined data sets of the first and second National Health and Nutrition Examination Surveys (NHANES I and II) of 1971-1974 and 1976-1980. Means and percentiles of upper arm muscle area were calculated for 3 cm increments in stature from 84 to 184 cm for boys and from 84 to 176 cm for girls. Based on means, Z-score units, and percentile ranges of upper arm muscle area by stature, five operational categories of nutritional status have been established. It is recommended that these standards and this classification system be used to supplement current standards of weight for age and weight for height in order to obtain a more complete assessment of body composition and nutritional status.     

Secular growth trends among children in Beijing (1955–2010)

ObjectivesTo analyze the growth trends of children in Beijing from 1955 to 2010.MethodsData for the period 1955–1975 were derived from published records. Data for the period 1985–2010 were derived from the Chinese National Survey on Students’ Constitution and Health (CNSSCH). Since 1985, the overall sampling and measurement methods have been consistent. The mean, the standard deviation, and the variance (ANOVA) of height, weight, and BMI by age and sex of students aged 7–17 were calculated and analyzed.ResultsBetween 1955 and 2010, the average height and weight of children in Beijing has increased. The average increments per decade for boys and girls were 2.45 cm and 2.03 cm in height and 2.68 kg and 1.68 kg in weight, respectively. The largest height increase per decade occurred between 1975 and 1985: 4.51 cm and 3.23 cm for boys and girls, respectively. The largest height increase for the entire 55-year period under study occurred among boys at age 13 (17.85 cm) and among girls at age 11 (15.90 cm.)ConclusionsDuring the period 1955–2010, growth trends among children in Beijing were positive. The health and nutritional status of these children improved significantly. Since 2007, might be related to government intervention, childhood obesity has been curbed.