Food prices jumping, insecurity to follow?

I am told by a retired analyst in the intelligence community that sharp rises in food prices are, along with the price of cooking fuels, a major leading indicator of future political unrest. So I was interested to see the following quotation in this report:

International prices of food increased by 4% during January and April 2014, putting an end to the declining trend of food prices sustained since August 2012. Prices of wheat and maize sharply increased during that period due to growing weather concerns and mounting import demand. Despite favorable prospects for cereals supplies, several uncertainties hang over the near future, some exerting upward pressures on prices, such as weather in the United States and, more globally, El Niño, and a hypothetical escalation of geopolitical tensions in Ukraine and others exerting downward pressures on export prices, such as the releases of public stockpiles of rice in Thailand. Domestic prices of food generally stabilized across regions, marked by seasonal trends and availabilities from previous harvests. . . . The thematic section of this report discusses the role that food prices and food shortages may have on food riots, a term widely used but poorly defined, and partially reflecting decades of overlooking the food-to-conflict nexus. Hence, monitoring food prices responds not only to food security and welfare interests, but also to political stability and security concerns. Proper monitoring constitutes a first step in addressing the complex interactions between food insecurity and conflict.