African countries can do more to reduce the number of malnourished children, according to international researchers.
Child malnutrition could affect nearly 42 million by 2025
The proportion of malnourished people in sub-Saharan Africa has remained at about 35% since 1970, the International Food Policy Research Institute said.
But population growth means the numbers affected rose to 200 million by 2001.
Further deterioration could be averted if African states invested more in farming and gained better access to rich world markets, the report says.
It warns that the number of malnourished children could grow from 38.6 million now to 41.9 million by 2025.
The report comes amid a severe food crisis in Niger - where up to three million people are suffering shortages.
42 million African children could face hunger by 2025
More spending in farming research needed
Investment in roads, education, and sanitation urgent
Rich countries must boost aid and reduce trade barriers
The UN says 32,000 children with severe malnutrition could face death without the necessary food and medical treatment.
Besides Niger, hunger also looms in neighbouring Mali, Burkina Faso and Mauritania.
The crisis was triggered by poor harvests and locusts last year.
The IFPRI report says the UN Millennium Development goal to halve child malnutrition in Africa by 2015 will fail unless more radical steps are taken now.
According to the Washington-based institute, the entire continent needs at least at least $303bn (£167bn) in new investment to halve hunger by 2015 - a prospect it describes as "daunting".
The lead author says the recent pledge by world's richest countries to double aid to the poorest, as well as a promise by African leaders to boost investment in agriculture, would be beneficial.
"Improved crop, land and water management must be supported," Mark Rosegrant said.
Building roads and boosting the information and communication technology sectors would have a positive impact too, the report says.
It also called for better access to world markets for African produce.
Trade liberalisation in agriculture would bring an additional $5.4b to Africa by 2025, it says.