"Our results challenge several programmes in countries of low and middle income countries…[for example], traditional school feeding programmes that increase BMI [body mass index] with little effect on height might be doing more harm than good in terms of future health.", explains lead author Linda Adair from the Gillings School of Global Public Health at the University of North Carolina at Chapel Hill in the USA.
"The present focus in LMICs on reducing the proportion of children under 5 years of age who are underweight might have detrimental repercussions if feeding interventions promote excess weight gain after the age of 2 years. Whereas, interventions that promote linear growth in early life could build human capital [height and levels of schooling] in adults without increasing the burden of non-communicable diseases."*
Until now, most early child growth research has focused on body weight and outcomes in later life rather than on the separate effects of length and weight gain. Additionally, questions remain about whether the promotion of infant and young child weight gain—important for survival and cognitive development—might also influence risk of adult chronic diseases later in life.
In this study, Linda Adair and colleagues working together in the COHORTS collaboration compared the potential long-term effects of faster weight gain and linear growth in infancy and childhood on height, schooling, blood pressure, glucose metabolism, and body composition in young adulthood.
Analysing data from five prospective birth cohort studies from Brazil, Guatemala, India, the Philippines, and South Africa, they showed that higher weight at birth and faster linear growth in the first 2 years of life were linked with increased adult height and higher levels of schooling.
Conversely, children that with high relative weight gain (weight gain above what would be expected given their height) after the age of 2 years and later in childhood had higher blood pressure, BMI, body fat levels, and plasma glucose concentrations in young adulthood.
According to the authors, "New interventions that specifically promote linear growth instead of weight gain should be developed, tested, and promoted; exclusive breastfeeding, high-quality protein (e.g., animal), and micronutrients could be further investigated."
Writing in a linked Comment, Zulfiqar Bhutta from The Aga Khan University, Karachi, Pakistan points out, "Although the evidence emerging from observational studies such as Adair and colleagues' is important for policy, well designed prospective studies with appropriate interventions and follow-up are clearly needed. The outcomes should include elements of child development, education, employment, and earnings, which would allow improved estimation of effect on human capital. Although expensive and difficult to organise and implement, such cohort studies are a crucial investment for the future and, in view of the interest in human development in the post-2015 era, should be prioritised for funding."
Notes to Editors:
*Quotes direct from author and cannot be found in text of Article.
Journal
The Lancet