Food production in one of Cameroon's poorest regions is likely to be further hit by insecurity just as food reserves run low with the approach of the lean season, said WFP.
"Sometimes we've got nothing to eat. Sometimes just enough for the children," said Gombo, a mother of five who left her village near the Nigeria border six months ago and is living in an informal settlement near Maroua.
"I try to make a living by cutting and selling firewood. People from the nearby village also help with food, but this is less now. I am farmer. I miss my village and working in the field."
Boko Haram fighters seized control of a swathe of northeast Nigeria last year, killing thousands in an unprecedented land grab while increasing incursions into neighbouring countries, including Cameroon.
The number of people in northern Cameroon who have fled their homes due to cross-border violence has tripled since January to 106 000, according to the UN's Office for the Co-ordination of Humanitarian Affairs (OCHA).
WFP has struggled to secure funds for its operations in Cameroon and in the past six months was only able to provide food assistance to 68 000 displaced people in April in May and only for two weeks.
"When we went back to these people I asked them if they had any food left and the answer was no," said Adel Sarkozi, WFP spokesperson.
She said that some 35% of children in border areas were malnourished.