Two major UN agencies have warned that a decline in breastfeeding in the Asia-Pacific region is lowering the survival rate of babies and children.
Breastfeeding benefits mother and child, many health experts say
The World Health Organisation and the UN children's agency, Unicef, say more needs to be done to inform parents of the risks of breast milk substitutes.
Health experts at a conference in the Philippines say breastfeeding is better for children's health.
The practice leads to lowered child mortality rates, doctors say.
Delegates to the conference in the Philippines' capital, Manila, were told that in Cambodia, where breastfeeding has been promoted, the child mortality rate has dramatically fallen.
In 2000, one in 10 Cambodian mothers were still breastfeeding their children when they were six months old.
Five years later, the figure had grown to six out of 10, says the BBC's Guy De Launey in Phnom Penh, Cambodia.
The comparable figure across Asia is 35%, says the WHO.
The child mortality rate in Cambodia dropped by a third in the same period and the WHO believes breastfeeding is largely to credit.
"It's not just a matter of cost - it's a matter of survival for infants in developing countries," Dr Chessa Lutter from the WHO told the BBC.
Infants born into conditions of poverty where there is not the access to clean water and adequate sanitation to safely feed infants formula milk, benefit from breastfeeding, she said.
Children in developed countries who are breastfed benefit too. They "have better cognitive development" and lower risk of Type 2 diabetes, Dr Lutter added.
Our correspondent says large billboards depicting a nursing mother and baby are a common sight in towns and rural areas in Cambodia and local authorities have created breastfeeding-friendly sites in villages.
The health experts meeting in Manila want the rest of the region to follow Cambodia's example.
They say more needs to be done to counter the marketing campaigns of makers of infant formula milk.
"The average family in the developing world, they don't breast feed because they think bottle feeding is better," said Karen Codling, a regional nutrition specialist at Unicef's Asia-Pacific office.
An association of milk formula companies in the Philippines has launched a legal challenge against a strict marketing code imposed on the industry last year.