Aamir endorsed the offer, in which capacity he would support Unicef's work to promote the right of South Asian children to nutrition.
In a programme organised in Kathmandu Thursday, the UN agency officially announced Aamir Khan as new Unicef ambassador after he visited Kapilvastu and Lumbini in west Nepal Wednesday to observe a locally initiated nutrition programme by women health volunteers, saving thousands of children from malnutrition, a common phenomenon in South Asia.
"I am delighted to become an ambassador of Unicef in South Asia. I hope my messages on the importance of children's nutrition will make parents, families at all levels support and adopt proven services and nutrition practices that will help children grow and develop to their full potential," Aamir said after his endorsement.
Child stunting remains one of the greatest development challenges in South Asia, he said, adding that stunted children have stunted bodies, stunted brains and stunted lives.
"Compared with children who are not stunted, stunted children have poorer cognitive development, often enrol later in school, complete fewer grades and learn less, leading to reduced productivity and income-earning in adult life," he added.
After sub-Saharan Africa, South Asia reports the highest number of deaths of children under the age of five - 2.3 million in 2011. In this region, 38 percent of the children under the age of five have stunted growth due to chronic under-nutrition.
In addition, an estimated 28 percent children are born with low birth weight, largely due to women's poor nutrition during and before pregnancy, according to Unicef.
During his three-day Nepal visit, Aamir also took part in the launch of the "1,000 Golden Days" national nutrition campaign.
The most crucial time to meet a child's nutrition needs is during the 1,000 days from conception to the child's second birthday. Proven and effective interventions during this time can prevent malnutrition and drastically reduce the prevalence of stunting.
Aamir has been chosen as ambassador at a time when the whole world is celebrating the 25th anniversary of the Convention on the Rights of the Child (CRC). The CRC has inspired domestic legislation to respect, protect and fulfil child rights in all eight countries of South Asia, as well as the creation of policy and national development plans for their implementation.
According to Unicef, pervasive poverty and disparities prevent millions of children in South Asia from living in dignity, reaching their potential and making choices about their own future.
"With the immense respect that Aamir Khan commands across South Asia, we are convinced that he will make a lasting difference in the fight against child stunting, potentially the biggest threat to children's growth and development in this part of the world," said Karin Hulshof, Unicef's regional director for South Asia.
