The Senlis Council said southern Afghanistan was facing serious food shortages which could play into the hands of the country's former leaders, Taliban.
The council said children were dying from hunger in makeshift camps set up in the south, many of them near military bases used by Nato forces for security and reconstruction operations.
Emmanuel Reinert, executive director of the Senlis Council, said there were 10 to 15 such camps in the region, each occupied by 10,000 people with one, near Lashkar Gar in the volatile Helmand province, having 6,000 families.
Reinert's organisation, an international policy think-tank with offices in London, Paris, Brussels and Kabul, based its research on testimony from Afghans and had videos showing malnourished children to back up its claims.
The Senlis Council argues that legalising and regulating many currently prohibited drugs would solve many of the world's problems by removing the global trade from the hands of criminal gangs.
The report, Afghanistan Five Years Later: The Return of the Taliban, also argues against the strategy of stopping production in Afghanistan.
It says eradication of the crop has resulted in a wave of starvation among destitute farming families across southern Afghanistan.
Instead of ripping up the plants, the report recommended using them for medicinal purposes in pain-relieving drugs such as morphine and codeine rather than as a narcotic.
The Senlis Council said aggressive drug policies reinforced the perception among the local Afghan communities that the US-led forces and the central government were leading an "anti-poor" policy.
It argues that this allows the Taliban to portray themselves as the protectors of the farming communities.
Afghanistan produces 92% of the world's opium, most of which is used in Europe, Russia, China, Iran and Central Asia, often as heroin.
A UN report this month said the crop will increase by nearly 60 per cent this year to a record 6,100 tonnes.