Children living in India's hills and mountains, especially at higher altitudes, are more likely to experience stunted growth, according to a recent research analyzing data from over 165,000 children under five years old in the country.
The study found that stunting was more common among third-born children and those with smaller sizes at birth. The prevalence of stunting was 36 per cent, with higher rates among older children. Living at altitudes above 2000 meters increased the risk by 40 per cent, as per research published in the open access journal BMJ Nutrition Prevention & Health.
GPS data were used to categorise altitude level while the World Health Organization (WHO) standard was used to define stunting.
Most, i.e. 98 per cent (164,874) of the children lived less than 1000 m above sea level while 1.4 per cent (2346) lived between 1000 and 1999m above sea level; and 0.2 per cent (335) lived at or above 2000m. Seven out of 10 lived in rural areas.
The overall prevalence of stunting among these children was 36 per cent, with a higher prevalence among children aged 18-59 months (41 per cent) than among those under 18 months of age (27 per cent).
Stunting was more common among children of third or higher birth order (44 per cent) than it was among firstborns (30 per cent). And stunting rates were even higher among those children who had been small or very small (45 per cent) at birth.
Mother's education emerged as an influential factor: stunting prevalence fell as maternal educational attainment rose. The proportion of children whose mothers had had no schooling was more than double that of children whose mothers had had a higher education.
Other protective factors included elements of antenatal care, such as clinic visits, tetanus vaccination, and iron and folic acid supplements; proximity to health facilities; and not belonging to a particular caste or indigenous tribe.
This is an observational study that captured a snapshot of the population at a specific point in time, making it difficult to confirm altitude as a cause of stunting, acknowledged the researchers.
But there are plausible explanations for their findings, they suggested. For example, chronic exposure to high altitude can reduce appetite, restrict oxygen delivery to tissues, and limit nutrient absorption.
Food insecurity also tends to be greater at higher elevations where crop yields are lower and the climate is harsher. Similarly, healthcare provision, including implementing nutritional programmes, and healthcare access are also more challenging, they suggest.
"In summary, concerted efforts are needed across health and nutrition sectors to address stunting, tailored to focus on higher-risk children in vulnerable areas," said the researchers.
