Higher birth weight, adding height in first two years protects against chronic diseases later
|April 02, 2013|
Promoting optimal birth weight and rapid growth in body length during the first two years of life is likely to lead to substantial improvements in adult height and completion of more grades of schooling, and may reduce risk factors for chronic disease in adulthood, especially in developing countries.
Those are among the findings of a new study published in The Lancet and led by Linda Adair, PhD, professor of nutrition at the Gillings School of Global Public Health at The University of North Carolina in Chapel Hill. The study, “Associations of linear growth and relative weight gain during early life with adult health and human capital in countries of low and middle income: findings from five birth cohort studies,” included 8,362 individuals from Brazil, Guatemala, India, the Philippines and South Africa.
“There’s been a lot of emphasis in high-income countries on how faster weight gain in infants may increase risk of obesity and related chronic diseases later in life,” Adair said. “But for children in low-income settings, faster infant growth may be the key to survival and healthy development. We wanted to understand all of the potential risks and benefits related to early growth patterns in these settings.”
Until now, most research relating early growth to adult health has focused only on body weight, without considering the separate effects of length and weight gain. In addition, not enough was known about how the timing of faster growth (whether it happened in infancy, early or late childhood) related to adult health.
Adair and her colleagues compared the potential long-term effects of faster linear growth and faster relative weight gain (putting on excess weight relative to height) in infancy and childhood on height, schooling, blood pressure, glucose metabolism and body composition in young adulthood. Data showed that higher weight at birth and faster height growth in the first two years of life was linked with increased adult height and higher levels of schooling. Conversely, children with more rapid relative weight gain after the age of 2 years and later in childhood had higher blood pressure, body mass index (BMI), body fat levels, and glucose concentrations in young adulthood. Therefore, for prevention of obesity and chronic disease risk in low-income settings, it is important to make sure that children don’t gain excess weight after age 2 years.
“Our results challenge several established programs, including traditional school feeding programs that increase BMI with little effect on height,” Adair said. “These actually might be doing more harm than good in terms of future health.”
The study suggests growth-monitoring programs, particularly in these types of countries, should incorporate length and height measurements, not just weight measurements. New interventions that specifically promote linear growth instead of weight gain should be developed, tested and promoted; exclusive breastfeeding, high-quality animal protein and micronutrients could be further investigated.
Adair adds that this type of study is important to bring together information from many low- and middle-income settings across the world.
“This is a true cohort study that brought together the research of people who have expertise in each country,” she says. “It really is an example of researchers working together across borders to produce a high-quality study of this nature. We are looking forward to doing more work like this together in the future.”
Co-authors include Caroline H.D. Fall, DM, and Clive Osmond, PhD, of University of Southampton (U.K.); Aryeh D. Stein, PhD, and Reynaldo Martorell, PhD, of the Rollins School of Public Health at Emory University, in Atlanta; Manuel Ramirez-Zea, MD, of the Instititue of Nutrition of Central America and Panama, in Guatemala City; Harshpal Singh Sachdev, MD, of the Sitaram Bhartia Institute of Science and Research, in New Delhi; Darren L. Dahly, PhD, of the University of Leeds (U.K.); Isabelita Bas, MA, of the University of San Carlos, Cebu, Philippines; Shane A. Norris, PhD, and Lisa Micklesfield, PhD, of the University of Witwatersrand, Johannesburg; and Pedro Hallal, PhD, and Cesar G. Victora, MD, of the Universidade Federal de Pelotas (Brazil).
The full study can be found online.