Table 5 Associations between conditional weight and length/height gain in infancy and childhood adjusted for each other and outcomes at age 14e15 years Conditional weight gain* Outcome b z SE p Value Systolic blood pressure (mm Hg) 0e6 mo 1.79 0.39 <0.01 6e12 mo 0.04 0.37 0.91 12e48 mo 0.89 0.41 0.03 BMI (kg/m2) 0e6 mo 1.38 0.21 <0.01 6e12 mo 0.78 0.19 <0.01 12e48 mo 2.35 0.23 <0.01 Sum of triceps and subscapular skin folds (mm) 0e6 mo 3.46 0.60 <0.01 6e12 mo 1.72 0.62 0.01 12e48 mo 6.06 0.79 <0.01 Subscapular/triceps ratio*102 0e6 mo 0.05 1.24 0.97 6e12 mo 0.04 1.12 0.97 12e48 mo 0.73 1.24 0.56 Conditional length/height gainy b z SE p Value 0.74 0.00 0.50 0.59 0.31 1.01 1.07 0.13 2.44 1.73 1.55 0.54 0.38 0.36 0.49 0.21 0.17 0.20 0.63 0.52 0.67 1.35 1.18 1.51 0.05 0.99 0.31 0.01 0.07 <0.01 0.09 0.80 <0.01 0.20 0.19 0.72 1993 Pelotas Birth Cohort, Brazil, 2008. *Adjustment for sex, skin colour, puberty status, socioeconomic level, pre-gestational BMI, smoking during pregnancy and length/height gain in the same period. yAdjustment for sex, skin colour, puberty status, socioeconomic level, pre-gestational BMI, smoking during pregnancy and weight gain in the same period. zChange in outcome per SD increase in conditional weight or length/height. b, beta coefﬁcient; BMI, body mass index; mo, months. contradicts the ﬁndings of some studies,33 34 although there is no consensus on such observations.35 In some populationsdfor example in Indiadcentral fat deposition is already evident in infants.36 By adjusting early growth variables for adolescent BMI or height (model 2 in tables 3 and 4), we addressed the question of to what extent the effects of early weight and height gains on later outcomes may be channelled through adolescent sizedwhich itself is partly a result of early growth patterns. For example, putting on weight rapidly in early life leads to larger BMI and height in adolescence, and early linear growth is also associated with adolescent height and to a lesser extent with adolescent BMI (table 2). In our view, the most important results from the public health perspective are those unadjusted for adolescent size (eg, model 1 in tables 3 and 4, and the models shown in table 5) because these address what might be expected from early interventions. The present study is, to our knowledge, the ﬁrst attempt to investigate long-term outcomes while mutually adjusting the effects of early weight and length/height gains. Also, by using the conditional method, we eliminated the correlation between growth variables in subsequent age ranges.15 16 A limitation of our cohort is the lack of measurements at the critical age of 2 years, which is widely regarded at the upper limit of the window of opportunity for preventing undernutrition.7 37 In low and middle-income countries, paediatric practice has included promoting rapid weight gain to prevent undernutrition and its harmful consequences.38 This is highly justiﬁed in soci- eties where undernutrition is responsible for a large proportion of the burden of disease,39 but in face of the nutrition transition there may be detrimental long-term consequences of rapid weight gain.7 Nevertheless, it has been proposed that in such societies, the beneﬁts of rapid weight gain in the ﬁrst 2 years regarding short-term morbidity and mortality outcomes, as well as long-term human capital outcomes, far outweigh its potential contribution to complex chronic diseases in adulthood.7 J Epidemiol Community Health 2012;66:149e154. doi:10.1136/jech.2010.124842 Maternal, child and adolescent health What is already known on this subject? Although there is longstanding evidence of the short-term beneﬁts of promoting rapid growth for young children in low-income settings, more recent studies suggest that early weight gain can also increase the risk of chronic diseases in adults. Supportive evidence on the beneﬁts of rapid early weight gain in poor populations is provided by its positive association with human capital in adults. Rapid weight gain up to about the age of 2 years is more strongly associated with positive outcomes, whereas rapid weight gain in late childhood is associated with negative outcomes. What this study adds? Conditional weight gains in all different age ranges up to 4 years tended to be associated with higher blood pressure, BMI and skin folds. In marked contrast, rapid length/height gains tended to afford protection against most of these outcomes, particularly those related to body composition. These results emerged when length/height gain and weight gain were adjusted for one another. Our ﬁndings suggest a new dimension to this debate, mainly that the promotion of rapid length/height gain without exces- sive weight gain may be beneﬁcial for long-term outcomes. If our results are conﬁrmed by other studies, it will be necessary to reassess the results of existing nutrition intervention studies to identify suitable strategies to achieve this growth pattern. Finally, our ﬁndings strongly support the need to monitor infant and child length/height in addition to the current practice of monitoring weight only.37 Acknowledgements This work was supported by the Wellcome Trust initiative: ‘Major Awards for Latin America on Health Consequences of Population Change’. Earlier phases of the 1993 cohort study were funded by the European Union, the National Program for Centers of Excellence (Brazil), the National Research Council (Brazil) and the Ministry of Health (Brazil). Funding The Wellcome Trust. Competing interests None declared. Ethics approval This study was conducted with the approval of the Federal University of Pelotas Ethics Committee (Brazil). Provenance and peer review Not commissioned; externally peer reviewed. REFERENCES 1. Chang SM, Walker SP, Grantham-McGregor S, et al. Early childhood stunting and later behaviour and school achievement. J Child Psychol Psychiatry 2002;43:775e83. 2. Martorell R, Ho TJ. Malnutrition, morbidity and mortality. Population Devel Rev 1984;10:49e68. 3. Victora CG, Barros FC, Horta BL, et al. Short-term beneﬁts of catch-up growth for small-for-gestational-age infants. Int J Epidemiol 2001;30:1325e30. 4. Singhal A, Lucas A. Early origins of cardiovascular disease: is there a unifying hypothesis? Lancet 2004;363:1642e5. 5. Ong KK, Loos RJF. Rapid infancy weight gain and subsequent obesity: Systematic reviews and hopeful suggestions. Acta Paediatrica 2006;95:904e8. 6. Sachdev HS, Fall CH, Osmond C, et al. 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