HCDC data showed that 38.7 per cent of nearly 900,000 primary school pupils screened were overweight or obese, including over 18 per cent who were obese.
The combined overweight and obesity rates were 33.6 per cent among lower secondary students and 25.4 per cent among upper secondary students.
Among children under five, 8 per cent were overweight or obese, while 4.4 per cent were underweight, 6.5 per cent were stunted and more than 3 per cent suffered from wasting.
HCDC said undernutrition was largely under control, but rising obesity had emerged as a new public health challenge, driven by urban lifestyles, unhealthy diets and non-communicable diseases.
Sedentary lifestyles, academic pressure, consumption of sugary and fast foods, misconceptions among adults and limited opportunities for physical activity were among the challenges in addressing childhood obesity.
Nationally, about 19.5 per cent of Vietnam's population, or around 20 million people, are overweight or obese, according to the World Health Organisation (WHO).
A National Institute of Nutrition survey found that the proportion of school-age children aged five to 19 who were overweight or obese rose from 8.5 per cent in 2010 to 19 per cent in 2020.
The rate was 26.8 per cent in urban areas, compared with 18.3 per cent in rural areas and 6.9 per cent in mountainous regions.
City steps up prevention
HCM City has introduced a range of measures, including strengthening school health services, conducting regular health screenings for early detection and providing closer weight monitoring and nutritional advice.
Training and awareness programmes on nutrition and physical activity are also being expanded across schools, health centres and hospitals.
By 2030, the city aims to standardise school meals, tighten canteen oversight and promote physical activity, while keeping overweight and obesity rates below 14 per cent for under-fives, 40 per cent for those aged five to 18 and 35 per cent for adults.
HCDC said effective intervention would require coordination between health authorities, schools and families, with programmes combining better nutrition and increased physical activity.
Huynh Thi Vu Quynh, head of the Nephrology and Endocrinology Department at Children's Hospital 2, said Vietnamese children were increasingly exposed to environments that raise the risk of obesity.
Easy access to unhealthy food, reliance on processed foods and snacks, and limited opportunities for physical activity were among the contributing factors.
Childhood overweight and obesity are associated with a range of health problems, including metabolic liver disease, cardiovascular disease, sleep apnoea and abnormal blood lipid levels.
On August 14, the city's health and education departments signed a memorandum of understanding with Danish health organisations under the Cities for Better Health programme.
HCM City is the first city in Vietnam and the 57th globally to join the network, which promotes cooperation in addressing health challenges including childhood overweight and obesity.