Legalizing recreational marijuana leads to increased sales of ice cream, cookies and chips, according to a first-of-its-kind study establishing a causal relationship between legal cannabis and junk food consumption. 

“You think marijuana does no harm — that’s pretty much the consensus today,” said Georgia State University economist Alberto Chong in an interview with The Academic Times. “But there are unintended consequences, and one of them is the fact that you really get very hungry and you start eating crap.”

Chong and co-author Michele Baggio of the University of Connecticut found that legalizing recreational marijuana causes junk food sales to rise by about 6.3% in terms of sales and 5.1% by volume. The authors presented their findings in the December 2020 issue of Economics & Human Biology. 

The researchers added that while the tendency to binge on junk food after smoking a joint may be a stoner stereotype, their findings have real implications for public policy at a time when more than 40% of American adults are obese, according to the Centers for Disease Control and Prevention.

Governments should consider the effects of marijuana on food consumption when considering whether to legalize recreational use of the drug, according to the researchers.

After smoking, Chong said, “You’re like, ‘I’m really hungry now’ … It’s what people always say, it’s what people always think, but this actually proves that.”

The researchers used county-by-county population data from the U.S. states of Colorado, Oregon and Washington, as well as Nielsen Retail Scanner data from between 2006 and 2016 for convenience store, drugstore and grocery store sales of junk food items. 

Colorado and Washington became the first states to legalize recreational marijuana in 2012. Oregon followed shortly thereafter in 2014. As of 2021, 15 states and the District of Columbia have legalized recreational marijuana. 

The state-by-state difference in the timing of recreational marijuana legalization helped Chong and Baggio observe a causal relationship between the drug and junk food sales. The researchers also controlled for demographic factors such as race, average age of population, unemployment rate and education. 

An earlier version of the paper included a breakdown of junk food sales by type that did not make it into Economics & Human Biology. Legal marijuana boosted sales of ice cream by 3.1%, cookies by 4.1% and chips by 5.3%, according to Chong and Baggio’s 2019 working paper, which was covered by the Economist magazine. 

While Chong typically works as a development economist, consulting for organizations such as the World Bank and the United Nations Development Program, he became interested in researching marijuana after Uruguay became the first country to legalize the drug in 2013. Since then, he and Baggio have written several eye-catching papers on the effects of legalization. 

In a 2020 paper for the Canadian Journal of Economics, Chong, Baggio and Sungoh Kwon of the Korea Institute of Public Finance found that legalizing marijuana led to a more than 12% drop in alcohol sales. The paper used similar metrics — U.S. state-level statistics and Nielsen sales data — as the more recent junk food study. 

Another study by Chong, Baggio and David Simon of the University of Connecticut found that legalizing marijuana leads to an overall increase in sexual activity, a reduction in use of contraceptives and an overall increase in number of births. That paper, titled “Sex, marijuana and baby booms,” was published in 2019 in the Journal of Health Economics. 

Chong told The Academic Times that he is tired of researching marijuana and wants to move onto other topics, but added that he has one more upcoming paper about the relationship between marijuana and domestic violence. He characterized his findings as “rather robust” and “somewhat startling,” but declined to comment further because the paper needs further work. 

The professor, who earned his Ph.D. from Cornell University, said that studying the effects of recreational marijuana in the U.S. is far easier than in other countries such as Uruguay and Canada that have also legalized the drug. 

“There’s so much data that you can exploit that you can’t find in other countries,” he said. 

When the economists submitted the original version of their junk food paper to Economics & Human Biology in 2019, it was just five pages long, according to Chong. However, the editor asked the researchers to expand on their work, and the final version runs 13 pages. 

The paper, titled “Recreational marijuana laws and junk food consumption,” was published in the December 2020 issue of Economics & Human Biology. The co-authors were Alberto Chong of Georgia State University and Michele Baggio of the University of Connecticut. Chong was lead author.