Childhood overweight and obesity have increased dramatically since 1990. These findings confirm the need for effective interventions starting as early as infancy to reverse anticipated trends.

Summary Background Low birthweight (LBW) of less than 2500 g is an important marker of maternal and fetal health, predicting mortality, stunting, and adult-onset chronic conditions. Global nutrition targets set at the World Health Assembly in 2012 include an ambitious 30% reduction in LBW prevalence between 2012 and 2025. Estimates to track progress towards this target are lacking; with this analysis, we aim to assist in setting a baseline against which to assess progress towards the achievement of the World Health Assembly targets. Methods We sought to identify all available LBW input data for livebirths for the years 2000–16. We considered population-based national or nationally representative datasets for inclusion if they contained information on birthweight or LBW prevalence for livebirths. A new method for survey adjustment was developed and used. For 57 countries with higher quality time-series data, we smoothed country-reported trends in birthweight data by use of B-spline regression. For all other countries, we estimated LBW prevalence and trends by use of a restricted maximum likelihood approach with country-level random effects. Uncertainty ranges were obtained through bootstrapping. Results were summed at the regional and worldwide level. Findings We collated 1447 country-years of birthweight data (281 million births) for 148 countries of 195 UN member states (47 countries had no data meeting inclusion criteria). The estimated worldwide LBW prevalence in 2015 was 14·6% (uncertainty range [UR] 12·4–17·1) compared with 17·5% (14·1–21·3) in 2000 (average annual reduction rate [AARR] 1·23%). In 2015, an estimated 20·5 million (UR 17·4–24·0 million) livebirths were LBW, 91% from low-and-middle income countries, mainly southern Asia (48%) and sub-Saharan Africa (24%). Interpretation Although these estimates suggest some progress in reducing LBW between 2000 and 2015, achieving the 2·74% AARR required between 2012 and 2025 to meet the global nutrition target will require more than doubling progress, involving both improved measurement and programme investments to address the causes of LBW throughout the lifecycle. Funding Bill & Melinda Gates Foundation, The Children's Investment Fund Foundation, United Nations Children's Fund (UNICEF), and WHO.

Objective: To quantify the prevalence and trends of stunting among children using the WHO growth standards. Design: Five hundred and seventy-six nationally representative surveys, including anthropometric data, were analysed. Stunting was defined as the proportion of children below 22SD from the WHO length-or height-for-age standards median. Linear mixed-effects modelling was used to estimate rates and numbers of affected children from 1990 to 2010, and projections to 2020. Setting: One hundred and forty-eight developed and developing countries. Subjects: Boys and girls from birth to 60 months. Results: In 2010, it is estimated that 171 million children (167 million in developing countries) were stunted. Globally, childhood stunting decreased from 39?7 (95 % CI 38?1, 41?4) % in 1990 to 26?7 (95 % CI 24?8, 28?7) % in 2010. This trend is expected to reach 21?8 (95 % CI 19?8, 23?8) %, or 142 million, in 2020. While in Africa stunting has stagnated since 1990 at about 40 % and little improvement is anticipated, Asia showed a dramatic decrease from 49 % in 1990 to 28 % in 2010, nearly halving the number of stunted children from 190 million to 100 million. It is anticipated that this trend will continue and that in 2020 Asia and Africa will have similar numbers of stunted children (68 million and 64 million, respectively). Rates are much lower (14 % or 7 million in 2010) in Latin America. Conclusions: Despite an overall decrease in developing countries, stunting remains a major public health problem in many of them. The data summarize progress achieved in the last two decades and help identify regions needing effective interventions.

Objectives: To compare growth patterns and estimates of malnutrition based on the World Health Organization (WHO) Child Growth Standards ('the WHO standards') and the National Center for Health Statistics (NCHS)/WHO international growth reference ('the NCHS reference'), and discuss implications for child health programmes. Design: Secondary analysis of longitudinal data to compare growth patterns (birth to 12 months) and data from two cross-sectional surveys to compare estimates of malnutrition among under-fives. Settings: Bangladesh, Dominican Republic and a pooled sample of infants from North America and Northern Europe. Subjects: Respectively 4787, 10 381 and 226 infants and children. Results: Healthy breast-fed infants tracked along the WHO standard's weight-for-age mean Z-score while appearing to falter on the NCHS reference from 2 months onwards. Underweight rates increased during the first six months and thereafter decreased when based on the WHO standards. For all age groups stunting rates were higher according to the WHO standards. Wasting and severe wasting were substantially higher during the first half of infancy. Thereafter, the prevalence of severe wasting continued to be 1.5 to 2.5 times that of the NCHS reference. The increase in overweight rates based on the WHO standards varied by age group, with an overall relative increase of 34%. Conclusions: The WHO standards provide a better tool to monitor the rapid and changing rate of growth in early infancy. Their adoption will have important implications for child health with respect to the assessment of lactation performance and the adequacy of infant feeding. Population estimates of malnutrition will vary by age, growth indicator and the nutritional status of index populations.

Objective: To describe the worldwide implementation of the WHO Child Growth Standards ('WHO standards'). Design: A questionnaire on the adoption of the WHO standards was sent to health authorities. The questions concerned anthropometric indicators adopted, newly introduced indicators, age range, use of sex-specific charts, previously used references, classification system, activities undertaken to roll out the standards and reasons for non-adoption. Setting: Worldwide. Subjects: Two hundred and nineteen countries and territories. Results: By April 2011, 125 countries had adopted the WHO standards, another twenty-five were considering their adoption and thirty had not adopted them. Preference for local references was the main reason for non-adoption. Weight-forage was adopted almost universally, followed by length/height-for-age (104 countries) and weight-for-length/height (eighty-eight countries). Several countries (thirty-six) reported newly introducing BMI-for-age. Most countries opted for sex-specific charts and the Z-score classification. Many redesigned their child health records and updated recommendations on infant feeding, immunization and other health messages. About two-thirds reported incorporating the standards into pre-service training. Other activities ranged from incorporating the standards into computerized information systems, to providing supplies of anthropometric equipment and mobilizing resources for the standards' roll-out. Conclusions: Five years after their release, the WHO standards have been widely scrutinized and implemented. Countries have adopted and harmonized best practices in child growth assessment and established the breast-fed infant as the norm against which to assess compliance with children's right to achieve their full genetic growth potential.