Poor breastfeeding has left seven million children under 5 years old undersized in Vietnam, the Health Ministry said in a report issued at a conference Friday.
The number accounts for 30 percent of children in the age group here.
The figure means Vietnam has the 13th worst rate of undersized children, according to a Tuoi Tre article that cited the report.
According to the ministry, the condition is the result of poor nutrition during the fetal period and the two first years of life.
Complete breastfeeding during the first six months plays an important role in children's growth and reducing the chances of infection with bacterial diseases, the report said.
But only ten percent of children in Vietnam have been fully breastfed during their first six months, according to the report.
The ministry said slick formula milk advertising campaigns have tricked many mothers into believing that they cannot provide enough milk for the proper growth of their children.
The ads have lead to fewer infants being breastfed, the report said.
A 2006 government resolution aimed to improve children's nutrition by restricting advertising for all products that can be used to replace breast milk.
The resolution banned the sale of food products designed for children under 6 months old, and it also prohibited hospitals from using formula milk for children under 12 months old or displaying formula milk products.
Under the resolution, health officials are not allowed to receive any products or valuable items displaying the names or logos of formula milk brands designed for children under 12 months old.
They are also banned from instructing or advising women to use any products other than breast milk for children under 6 months old, except when necessary.
But a recent UNICEF survey conducted at children's and obstetrics hospitals nationwide showed that many mothers feed their children with products other than breast milk under the advice of medical officials.
The ministry's report also blamed the problem on a government policy that gives employed mothers only four months of maternity leave.