All over the world, people engage in behaviors that are risky for their health. They smoke, use illicit drugs, drink too much alcohol, eat unhealthy food or adopt sedentary lifestyles, and have risky sexual encounters. As a consequence, they endanger their health, reduce their own life expectancy, and often impose harmful consequences on others.
In a new World Bank book, Risking your Health: Causes, Consequence and Interventions to Prevent Risky Behaviors , we regroup these five risky behaviors – drugs, smoking, alcohol, unhealthy food and risky sex – and investigate them under a common lens, describing global trends in prevalence and discussing determinants and consequences. The book reviews empirical evidence to examine what works and what doesn’t to prevent those behaviors. Legislation and taxation, for example, can be effective, especially when combined with strong enforcement mechanisms. Cash transfers also have proven to be promising in some settings. Behavior change campaigns, such as school-based sex education and calorie-labeling laws, are often less effective on their own.
Despite recent progress in prevention and treatment, the HIV/AIDS epidemic –one of the most devastating consequences of risky sex— remains a heavy burden in sub-Saharan Africa, especially in its southern cone where between 11% and 26% of all adults are HIV-positive. Drug and alcohol abuse have been relatively stable over the past decade, but smoking and obesity linked to unhealthy diets and physical inactivity are on the rise in many developing countries and have the potential to substantially increase mortality and morbidity.
Close to 20% of the world’s adult population smokes cigarettes; globally, smoking causes more than 15% of premature deaths among men and 7% among women. While smoking prevalence is decreasing in the developed world, it is on the rise in many developing countries. Obesity is also increasing in the developing world, especially in the Middle East, Latin America and the Caribbean and the Pacific Islands where many countries are experiencing obesity rates above 20% for males and more than 40% for females.
By engaging these risky behaviors, individuals are trading their long-term well-being for immediate satisfaction. Indeed, one trait that is shared by these behaviors is the disconnect between the pleasure or satisfaction they provide and the consequences they entail. If smoking killed quickly, few people would choose to light a cigarette. But there is usually a long lag between the enjoyment of the “guilty pleasure” and the negative health consequences. Moreover, these health behaviors are considered to be “risky” because the outcomes are not always certain. Not all smokers die from lung cancer, not all heavy drinkers suffer from liver cirrhosis, and not everyone who has multiple sexual partners without using condoms becomes HIV-positive.
In contrast with other ailments, the illnesses caused by these risky behaviors are, ultimately, the result of decisions made by individuals, even if those decisions have complex motivations. Individuals decide to light a cigarette, consume drugs, order alcoholic drinks, eat junk food, or have unprotected sex.
But, if they are the results of individual decisions, risky behaviors rarely occur in isolation. Peer pressure, parental influences, networks, and social norms often play important roles in the choices to initiate, continue, or quit those behaviors. Even if they might be the first to suffer, the consequences of risky behaviors are rarely limited to those engaging in them. In certain cases, the link is direct: drug consumption, smoking, alcohol use, poor diet, and HIV among mothers have detrimental impacts on their fetuses; second-hand smoking is a serious health hazard to others; and unprotected sex and needle-sharing lead to the spread of HIV and other sexually transmitted infections. In other cases, the link is less direct but not necessarily less real: the long-term health consequences of many of these behaviors are costly and could stretch households’ finances and exacerbate poverty. Finally, these risky behaviors have consequences for society as a whole, since they often trigger significant public health expenditures and lead to declines in aggregate productivity through premature mortality and morbidity.
The costly impacts that accrue to individuals in developing countries, in addition to the presence of large negative spill-overs, suggest that public intervention to prevent or reduce engagement in these behaviors can improve overall welfare. How can the individual decisions to consume drugs, tobacco or alcohol, eat junk food or engage in risky sex be influenced by public interventions?
Providing information about the dangers associated with the risky behaviors is important, but is rarely enough. People have known for years that tobacco kills, but many continue to smoke. They know how HIV is transmitted and how to prevent infections, but many prefer not to use condoms, even though they are widely available.
Economic mechanisms such as taxes, for example on alcohol and tobacco products, by raising the price of the “guilty” pleasure, have the advantage of directly affecting the trade-off between immediate satisfaction and long-term well-being. Tobacco or alcohol taxes have been very effective at decreasing consumption, as illustrated by the figure below for cigarette taxes in the US. Such taxes are a “win-win” since they decrease the prevalence of risky behaviors while also increasing government revenue. They are also used by many developing countries and their introduction and expansion should be further encouraged.
FIGURE. Cigarette sales and average price per pack* --- United States, 1970--2008
SOURCE: Chaloupka FJ. The economics of tobacco taxation. Chicago, IL: ImpacTEEN, University of Illinois at Chicago; 2009. Available at http://www.impacteen.org/generalarea_PDFs/Chaloupka_TobaccoTaxes_AK_041609.pdf .
* Adjusted to February 2009 dollars.
Changing private, self-destructive behaviors is difficult, but we are gradually developing a better understanding of them and better policy tools to deal with the growing threat they represent.
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Press Release: Risky Behaviors Constitute Growing Threats to Global Health 
Report: Risking Your Health : Causes, Consequences, and Interventions to Prevent Risky Behaviors 
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