Since the beginning of 2014, riots have occurred in countries including Thailand and Venezuela. Although they’re different cultures on different continents, these mass protests movements may all have one commonality; increasing food prices may have contributed to their occurrence. The cost of food has been steadily increasing in both Thailand and Venezuela; last month demonstrators in Caracas took to the streets marching with empty pots to protest food shortages. According to Dr. Yaneer Bar-Yam and fellow researchers at the New England Complex Systems Institute (NECSI), events such as these may be anticipated by a mathematical model that examines rising food costs.

The events of 2014 aren’t without precedent; the price of food has provoked (and placated) throughout history, beginning in Imperial Rome when Augustus introduced grain subsidies. In recent years, the Middle East has been particularly affected by the cost of grain. Centuries after Egypt developed bread as we recognize it, the nation experienced a bread intifada--the country rioted for two days in January 1977 following Anwar Sadat’s decision to drastically decrease food subsidies. More recently, under the rule of Hosni Mubarak, the price of grain rose 30 percent between 2010 and 2011. Then, on January 25, 2011 a new revolution began in Egypt.

The surging cost of grain throughout the Middle East, along with Tunisian fruit and vegetable vendor Mohammed Bouazizi setting himself on fire on December 17, 2010, are frequently cited as factors contributing to the Arab Spring. Four days prior to Bouazizi’s self immolation, Bar-Yam and his NECSI colleagues submitted an analysis that highlighted the risks of rising food prices and anticipated an event like the Arab Spring. Their research included a model built using data from the United Nations Food and Agriculture Organization’s Food Price Index, a measure that maps monthly changes in international food costs. The model found the likelihood for rioting increased when the index reached above 210.

On the graph below, the black dots are food prices and the vertical red lines are riots (with death tolls in parentheses); they show the index exceeded 210 during the food crises of both the 2008 and 2011.

Of course, man cannot riot off bread alone; factors such as unemployment, oppression, economic instability and corruption also contribute. Still, there is something so fundamental about food, and the implications of not having it, that makes people react. As Bar-Yam explains, “The analysis suggests the doubling of food prices we have seen since 2005 pushed many in the greatest poverty across the line from bare subsistence into desperation and starvation. When people are not able to feed their families, they have little to lose and become willing to take strong actions.”

Bar-Yam has identified two main factors he believes are driving the increasing food prices. The first, conversion of corn for ethanol, is more of an underlying factor. Since 2005, the demand for corn has increased so it can be converted to ethanol and used as gasoline. The other, speculation on food commodities, leads to bubbles and crashes; this occurred in both 2008 and 2011. Both of these factors can be seen on the graph below:

What can be expected for the future? The UN food price index has been at the 210 threshold for nearly two years and reached 213 in March 2014. Along with local conditions and policy decisions that affect food prices, Bar-Yam sees addressing speculation and the conversion of corn to ethanol as essential to determining future conditions. He says, “If actions are taken that reduce the amount of corn being converted to ethanol, prices will decrease, and if there is new regulation of commodity speculation the possibility of another peak will be reduced. However, as it currently stands, we have a very high base price due to ethanol conversion, and speculation may still lead to another bubble causing even more suffering and social unrest.”

Image Credits: Ahmad Hammoud, Graph 1 & 2 used with permission by NECSI