Collectively, young adults are significantly more likely to abuse drugs or alcohol than people in younger or older age groups. One of the key factors in determining the likelihood of substance intake is the amount of self-perceived risk that an individual attaches to drug or alcohol consumption. As part of a yearly survey project called Monitoring the Future, federally sponsored researchers from the University of Michigan ask a nationally representative group of young adults between the ages of 18 and 30 how much risk they associate with varying levels of substance use. Monitoring the Future Monitoring the Future is sponsored by the National Institute on Drug Abuse, which forms part of the National Institutes of Health. Every year, the University of Michigan researchers who run the project ask thousands of U.S. 8th, 10th and 12th graders to assign a level of risk to isolated substance experimentation, occasional substance use and regular substance use. In addition, the researchers ask each group of 12th graders participating in Monitoring the Future to continue to report their annual involvement in substance use, as well as the attitudes they typically hold toward substance use. The survey\u2019s research staff separately analyzes the yearly responses provided by 18-year-olds, young adults between the ages of 19 and 22, young adults between the ages of 23 and 26, and young adults between the ages of 27 and 30. Alcohol Use In 2013, 9.9 percent of Monitoring the Future\u2019s nationally representative 18-year-olds viewed isolated consumption of one or two servings of alcohol as a \u201cgreat risk\u201d to their health and wellbeing. This number dropped to 5.8 percent among 19- to 22-year-olds, 4.3 percent among 23- to 26-year-olds and 4 percent among 27- to 30-year-olds. Almost a quarter (23.1 percent) of all 18-year-olds considered daily consumption of one or two alcohol servings a great risk. Again, perceived risk tapered off in the older age groups, reaching a low of 17.4 percent in 27- to 30-year-olds. Nearly 64 percent of 18-year-olds viewed habitual consumption of four or five daily alcohol servings as a serious health risk (a perspective supported by extensive scientific research). All three older age groups under consideration were more likely to view this level of alcohol intake as seriously risky; the peak rate of perceived risk, 69.7 percent, occurred among 23- to 26-year-olds. Nearly 46 percent of 18-year-olds viewed the weekend consumption of five or more alcohol servings per day as a great risk (an opinion also supported by scientific research). The perceived risk associated with this activity tapered off in each older group and reached a low of 37.2 percent in 27- to 30-year-olds. Marijuana Use In 2013, 14.5 percent of the nationally representative 18-year-olds participating in Monitoring the Future viewed isolated episodes of marijuana experimentation as a great risk to their health and well-being. All other age groups under consideration were less likely to view marijuana experimentation as risky, with the lowest rate of perceived danger (9.7 percent) occurring among 23- to 26-year-olds. Roughly equal numbers of 18-year-olds and 19- to 22-year-olds considered occasional marijuana use a great risk (19.5 percent and 19.1 percent, respectively). The rate of perceived danger fell to 10.2 percent in 27- to 30-year-olds and 9.7 percent in 23- to 26-year-olds. Almost identical numbers of 18-year-olds and 19- to 22-year-olds viewed regular intake of marijuana\u2014a practice firmly associated with steeply heightened odds for cannabis addiction\u00a0\u2014 as a serious health risk (39.5 percent and 39.4 percent, respectively). However, the highest rate of perceived risk (40.3 percent) occurred among 27- to 30-year-olds. The lowest rate (35.9 percent) occurred among 23- to 26-year-olds. Trends in Harm Perception Generally speaking, the yearly figures compiled through Monitoring the Future indicate that the level of perceived risk that young adults attach to heavy alcohol use fell somewhat between 2012 and 2013. However, none of the age groups under consideration experienced enough attitudinal change to significantly increase their odds of participating in heavy alcohol intake. The picture for the perceived risk of marijuana use is somewhat different. Between 2012 and 2013, 27- to 30-year olds experienced a statistically significant decline in their perception of the risk associated with marijuana experimentation. Those ages 23 to 26 experienced a statistically significant decline in their perception of the risk associated with occasional marijuana intake, while 18-year-olds experienced a significant decline in their perception of the risk associated with regular marijuana intake.