Other aid officials have used more dramatic language.
UN Secretary-General Ban Ki-moon has said dearer food risked wiping out progress on cutting poverty and his special rapporteur on the right to food, Jean Ziegler, said rises were leading to "mass murder".
Brown raised further doubts about the wisdom of using crops to help produce fuel, an idea whose recent popularity in the US and Europe has been dented by fears it harms the environment and makes food dearer.
"We need to look closely at the impact on food prices and the environment of different production methods and to ensure we are more selective in our support (for biofuels)," he said.
"If our UK review shows that we need to change our approach, we will also push for change in EU biofuels targets."
The EU's executive Commission on Monday stood by its target of getting 10 percent of road transport fuel from crops and agricultural waste by 2020.
Brown called for more research into higher-yielding crop varieties that can withstand harsh climates and for an agricultural revolution in developing countries.
A global trade deal that opened up markets in rich countries was also needed, he said.