According to this new paper of mine titled “Rising Food Prices, Food Price Volatility, and Political Unrest,” the answer is a qualified yes:
“Do food prices cause political unrest? Throughout history, riots appear to have frequently broken out as a consequence of high food prices. This paper studies the impact of food prices on political unrest using monthly data on food prices at the international level. Because food prices and political unrest are jointly determined, the incidence of natural disasters in a given month is used in an attempt to identify the causal relationship between food prices and political unrest. Empirical results indicate that between January 1990 and January 2011, food price increases have led to increased political unrest, whereas food price volatility has been associated with decreases in political unrest. These findings are consistent with those of the applied microeconomics literature on the welfare impacts of food prices.”
In other words, there is good evidence that rising food prices cause political unrest, but the evidence suggests that food price volatility does the exact opposite, although this latter effect cannot be argued to be causal and could only be a correlation.
If you would like a copy of the paper, you can download it from SSRN or on MPRA (opens a .pdf document). It goes without saying that I am grateful in advance for reader comments and suggestions.