Record prices, conflicts and extreme weather combined to drive the number of people vulnerable to starvation up to 108 million last year, according to a UN and EU-backed report published Friday.
The global total of people deemed "severely food insecure" represents a 35 percent increase on the 80 million considered to be in that dangerously exposed position in 2015.
The term refers to people already suffering from acute malnutrition or lacking enough food to provide their basic energy requirements on a sustainable basis.
It can include households who can only survive by, for example, slaughtering their animals and thus depleting their future ability to produce food.
The report warns that the food insecurity crisis is set to worsen this year with four parts of the developing world, South Sudan, Somalia, Yemen and northeast Nigeria, at risk of famine.
The report was produced under the joint auspices of the European Union, UN agencies including the Food and Agriculture Organisation (FAO) and USAID/FEWSNET along with some regional food security institutions.
Extreme weather factors blamed for the deteriorating situation included drought and erratic rainfall caused by the El Nino phenomenon.
But civil conflict was the driving factor in nine of the 10 worst humanitarian crises, the 2017 Global Report on Food Crises says.
Other countries facing widespread food insecurity this year are Iraq, Syria (including refugees in neighbouring countries) Malawi and Zimbabwe.
"In the absence of immediate and substantive action not only to save people's lives, but also to pull them back from the brink of famine, the food security situation in these countries will continue to worsen in coming months," the report says.
FAO Director-General Jose Graziano da Silva said: "We can prevent people dying from famine but if we do not scale up our efforts to save, protect and invest in rural livelihoods, tens of millions will remain severely food insecure."
Ertharin Cousin, Executive Director of the World Food Programme, said food insecurity was not just a humanitarian issue.
"Hunger exacerbates crisis, creating ever greater instability and insecurity," he said. "What is a food security challenge today becomes tomorrow's security challenge.
"It is a race against time -- the world must act now to save the lives and livelihoods of the millions at the brink of starvation."
© 2017 AFP