The World's Deadliest Behavioral Risk Factors

"Smoking kills" is but one of the slogans connected to anti-tobacco advocacy groups — and it's quite true. When looking at behavioral risks, meaning types of risk that can largely be avoided, especially in highly industrialized nations, smoking cigarettes, cigars and other tobacco products is connected to a variety of diseases responsible for 7.7 million deaths worldwide. As our chart with data from the 2019 Global Burden of Disease study by the Institute for Health Metrics and Evaluation at the University of Washington shows, no other behavioral risk factor comes close to the disease burden of smoking.

Coming in second on a global level as well as in terms of risk-factor-associated deaths in the United States in 2019 is alcohol use with an estimated 2.4 million global and 137,000 U.S. deaths in 2019. Roughly 57 and 30 percent of global deaths associated with risk factors and connected to substance abuse and digestive diseases, respectively, can be traced back to alcohol use. While a high-sodium diet is connected to almost two million deaths on a global scale and therefore ranks third worldwide, the United States have a different problem: drug abuse.

In 2019, around 105,000 people were estimated to have died from diseases connected to drug use, which constitutes a four-percent share of the overall deaths connected to behavioral risks in the country. This is especially striking compared to the same metric globally, where the share of deaths barely reaches one percent. The total number of deaths from risk factors in the United States amounted to 1.8 million, while the global number stood at 35 million.

While the consumption of most drugs is illegal and often carries a social stigma, alcohol and tobacco are legal drugs permeating all levels of society. The risks of both are well-known and well-documented, with the International Agency for Research on Cancer classifying both as a group 1 carcinogen, which includes agents with "sufficient evidence of carcinogenicity in humans [and] both strong evidence in exposed humans that the agent exhibits key characteristics of carcinogens and sufficient evidence of carcinogenicity in experimental animals."