Prevalence and trends of stunting among pre-school children, 1990-2020

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 -2SD 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.