Underage drinking and associated problems have profound negative consequences for underage drinkers, their families, their communities, and society as a whole. Underage drinking contributes to a wide range of costly health and social problems, including motor vehicle crashes (the greatest single mortality risk for underage drinkers); suicide; interpersonal violence (e.g., homicides, assaults, rapes); unintentional injuries such as burns, falls, and drowning; brain impairment; alcohol dependence; risky sexual activity; academic problems; and alcohol and drug poisoning. On average, alcohol is a factor in the deaths of approximately 4,700 youths in the United States per year, shortening their lives by an average of 60 years (Centers for Disease Control and Prevention [CDC] Alcohol-Related Disease Impact [ARDI] software, 2009b).
Data show modest reductions in underage drinking and some progress toward the goals of the
Comprehensive Plan to Prevent and Reduce Underage Drinking (Substance Abuse and Mental Health Services Administration [SAMHSA], 2006), but there is still cause for concern. For example, in 2009, 39 percent of 20-year-olds reported binge drinking (drinking at levels substantially increasing the risk of injury or death) in the past 30 days; about 14 percent of 20-year-olds had, in those 30 days, binged five or more times.
Although drinking levels are lower at younger ages, patterns of consumption across the age spectrum pose significant threats to health and well-being. Particularly troubling is the erosion of the traditional gap between underage males and females in binge drinking. This gap is disappearing as females drinking practices converge with those of males. Thus, females are at increasing risk of alcohol-related mortality and morbidity, including sexual violence.
Still, there is reason for optimism. As discussed in Chapters 3 and 4 of this Report, States are increasingly adopting comprehensive policies and practices to alter the individual and environmental factors that contribute to underage drinking and its consequences; these can be expected to reduce alcohol-related death and disability and associated health care costs. These efforts can potentially reduce underage drinking and its consequences and change norms that support underage drinking in American communities.
CHARACTERISTICS OF UNDERAGE DRINKING IN AMERICA
Alcohol Is the Most Widely Used Substance of Abuse Among American Youth
Alcohol continues to be the most widely used substance of abuse among Americas youth, a greater proportion of whom use alcohol than use tobacco or other drugs. For example, according to the 2009 Monitoring the Future study, 30.4 percent of 10
Binge drinking is the most common underage consumption pattern. High blood alcohol concentrations and impairment levels associated with binge drinking place binge drinkers and those around them at substantially elevated risk for negative consequences. Thus, reducing binge drinking has become a primary public health priority.
Binge rates increase rapidly with age (Figure E.1); in 2009 approximately 6.9 million youth 12 to 20 years old (18.1 percent) reported binge drinking in the past month (SAMHSA, 2010). Although youth generally consume alcohol less frequently and less overall than adults, when they do drink, they are much more likely to binge drink (Figure E.2). Accordingly, most youth alcohol consumption occurs in binge drinking episodes. For example, 92 percent of the alcohol consumed by 12- to 14-year-olds is through binge drinking (Pacific Institute for Research and Evaluation [PIRE], 2002). A significant proportion of underage drinkers consume substantially more than the five-drink binge criterion. For example, averaged 2008 and 2009 data show that 12.1 percent of underage drinkers had nine or more drinks during their last drinking occasion (SAMHSA, Center for Behavioral Health Statistics and Quality [CBHSQ]
2, NSDUH, 2010). It is important to note that very young adolescents, because of their smaller size, reach BACs achieved by binge drinking by older adolescents (e.g., age 18 or older) with fewer drinks (3-4 drinks for persons ages 12-15) (Donovan, 2009).
Binge drinking is the consumption of a large amount of alcohol over a relatively short period of time. No common terminology has been established to describe different drinking patterns. Based on National Survey on Drug Use and Health (NSDUH) data, SAMHSA defines binge drinking as five or more drinks on one occasion on at least one day in the past 30 days and heavy drinking as five or more drinks on at least 5 different days in the past 30 days. Some studies, including Wechslers (2002) survey of college students, define binge drinking as five or more drinks in a row for men and four or more for women. Other sources use frequent heavy drinking to refer to five or more drinks on at least five occasions in the last 30 days. Appendix A discusses these differences in more detail.
Female Youth Drinking Rates Are Converging With Male Youth Rates
The convergence of female youth rates of consumption with those of male youth and the implications of this trend are causes for concern. Although older adolescent rates of consumption and binge drinking are higher for males than females, the gap is closing. In 2009, 30.5 percent of male 12
th graders reported binge drinking (consumption of 5 or more drinks in a row) at least once in the prior 2-week period, as compared to 20.2 percent of female 12th graders (Figure E.3) (Johnston, personal communication, 2010) This is a difference of 10.3 percentage points, compared with a 23 percentage difference in 1975. Adolescent females (e.g., 8th graders), now exhibit rates of drinking, binge drinking, and getting drunk similar to rates for adolescent males (Johnston et al. 2009a, Johnston, personal communication, 2010).
The literature on gender-specific effects of alcohol suggests that the health status of young women may be adversely affected by current trends in their consumption of alcohol. The literature states that certain consequences of alcohol use (e.g., unintended pregnancy, sexually transmitted diseases, and interpersonal violence) may be expected to increase.
Adolescents Beverage Preferences Are Shifting From Beer to Distilled Spirits
Different alcohol beverage types may be associated with different patterns of underage consumption. Ease of concealment, palatability, alcohol content, marketing strategies, and economic and physical availability may all contribute to the quantity of and settings for consumption. Similarly, beverage types may affect the policies and enforcement strategies that are most effective in reducing underage drinking (CDC, 2007). Tracking beverage preferences among young people is, therefore, an important aspect of prevention policy.
Distilled spirits are becoming more popular among adolescents and are challenging beer as the beverage most likely to be consumed by underage drinkers, especially among youth who report binge drinking. Flavored alcoholic beverages are also popular with adolescents. Females, in particular, have shifted their beverage preference from beer to these other alternatives (Figure E.4). However, wine remains a relatively unpopular beverage among younger drinkers.
There is some evidence that beverage preferences vary by State. Data from four states indicated that, among students in 9
th through 12th grades who reported binge drinking, liquor was the most prevalent beverage type (CDC, 2007).
Youth Start Drinking at an Early Age
It is increasingly clear that early initiation to alcohol use is associated with a variety of developmental problems during adolescence as well as problems in later life. These include intentional and unintentional injury to self and others after drinking (Hingson and Zha, 2009; Hingson et al., 2000); violent behavior, including predatory violence and date violence (Blitstein et al., 2005; Ellickson et al., 2003; Ramisetty-Milker, 2006); criminal behavior (Eaton et al., 2007); prescription drug misuse (Hermos et al., 2008); unplanned and unprotected sex (Hingson et al., 2003); motor vehicle crashes (Hingson et al., 2002) and physical fights (Hingson et al., 2001). Accordingly, increases in the age of alcohol initiation may significantly improve later health.
Although the peak years of initiaition to alcohol are 7th to 11th grade, 10 percent of 9- to 10-year-olds have already started drinking (Donovan et al., 2004) and more than one fifth of underage drinkers begin before they are 13 years old (Eaton et al., 2008). In fact, an estimated 2,842 young people ages 12 to 14 initiated alcohol use per day in 2009 (SAMHSA, CBHSQ, NSDUH, special data analysis, 2010). This means slightly more than 1 million (1,038,000) youth under age 15 years initiate alcohol use each year.
Drinking Rates Vary Significantly by Racial and Ethnic Group
White youth ages 12 to 20 are more likely to report current alcohol use and binge drinking than any other racial or ethnic group. Asian and Black youth had the lowest rates (Figure E.5; SAMHSA, CBHSQ, NSDUH, special data analysis, 2010); however, data indicate that prevalence of drinking before age 13 is higher among Blacks and Hispanics than White youth
These ethnic and racial differences must be viewed with caution. As Caetano and colleagues (1998) note, there are important differences in alcohol use and related problems among ethnic and racial subgroups of Whites, Blacks, Hispanics, Asians, and Native Americans/Alaska Natives. Moreover, they stress that the patterns of consumption for any group or subgroup represent a complex interaction of psychological, historical, cultural, and social factors that are not adequately captured by a limited set of labels. With these cautions in mind, however, the data in Figure E.5 highlight the importance of considering race and ethnicity in planning underage drinking countermeasures in specific communities.
Underage Drinking, Particularly Heavy Drinking, Is More Likely To Occur in Private Residences Where Three or More People Are Present
The social and physical settings for underage drinking affect patterns of alcohol consumption. For young people, the usual number of drinks consumed is substantially higher when two or more other people are present than when drinking with one person or alone (Figure E.6). Drinking in the presence of others is by far the most common setting for young drinkers. Over 80 percent of youth who had consumed alcohol in the past month reported doing so when at least two others were present (SAMHSA, 2010). Thus, most young people are drinking in social contexts that appear to promote heavy consumption and where people other than the drinker may be harmed by the drinkers behavior.
As shown in Figure E.7, private residences are the most common setting for youth alcohol consumption, although age differences are reported. Most underage drinkers reported drinking in either someone elses home or their own. The next most popular drinking locations were at a restaurant, bar, or club; at a park, on a beach, or in a parking lot; or in a car or other vehicle (SAMHSA, CBHSQ, NSDUH, special data analysis, 2010). Those 18 to 20 years of age are more likely than their younger peers to report drinking in restaurants, bars, or clubs, or at concerts or sporting events, although the absolute rates of such drinking are low when compared with drinking in private residences.
These data suggest that underage drinking primarily occurs in social settings (three or more drinkers) at a private residence. This conclusion is consistent with research that has found that underage drinking parties, where large groups of underage persons gather at private residences, are high-risk settings for binge drinking and associated alcohol problems.
Young People Perceive Alcohol To Be Readily Available
Since 1993, youth have reported declines in alcohol availability. However, the number of young people who report that alcohol is fairly easy or very easy to obtain remains high (Johnston et al., 2009c). Very young drinkers are most likely to obtain their alcohol at home from parents, siblings, or storage. It is important to note that some of the methods young people use to obtain alcohol do not violate underage drinking laws in some States (see Chapter 4).
Drinking Continues To Be Prevalent in Campus Culture at Many Universities
Eighty-two percent of college students drink and 40 percent report drinking five or more drinks on an occasion in the past 2 weeks (Johnston et al., 2009b). Research indicates that some college students drinking far exceeds the minimum binge criterion of five drinks per occasion (Wechsler et al., 1999). Although colleges and universities vary widely in student binge drinking rates, overall rates of college student drinking and binge drinking exceed those of non-college-age peers (Johnston et al., 2009b).
Unlike high school students and non-college-age peers, rates of binge drinking among college students have shown little decline since 1993 (Johnston et al., 2009b). These differences are not easily attributable to differences between college and non-college-bound students. Although college-bound 12th-graders are consistently less likely than their non-college-bound counterparts to report occasions of heavy drinking, college students report higher rates of binge drinking than college-age youth not attending college (Johnston et al., 2009b; Figure E.8). This suggests that the college environment influences drinking practices (Hingson et al., 2002; Kuo et al., 2003).
Youth Drinking Is Correlated With Adult Drinking Practices
Generational transmission has been widely hypothesized as one factor shaping the alcohol consumption patterns of young people. For example, children of parents who binge are twice as likely to binge themselves and to meet alcohol dependence criteria. Whether through genetics, social learning, or cultural values and community norms, researchers have repeatedly found a correlation between youth drinking and the drinking practices of parents (Pemberton, et al., 2008). Nelson and colleagues (2009) recently demonstrated this relationship at the population (State) level. State estimates of youth and adult current and binge drinking from 1993 through 2005 were significantly correlated when pooled across years. These results suggest that some policies primarily affecting adult drinkers (e.g., pricing and taxation, hours of sale, on-premises drink promotions) may also affect underage drinking.
CONSEQUENCES AND RISKS OF UNDERAGE DRINKING
Alcohol-Related Motor Vehicle Crashes
The greatest single mortality risk for underage drinkers is motor vehicle crashes (Figure E.9). Mile for mile, teenagers are involved in three times as many fatal crashes as all other drivers (National Center for Statistics and Analysis [NCSA], 2009). Compared with adults, young people who drink and drive have an increased risk of alcohol-related crashes because of their relative inexperience behind the wheel and their increased impairment from similar amounts of alcohol. One study found that at 0.08 BAC, adult drivers in all age and gender groups compared
to sober drivers were 11 times more likely to die in a single vehicle crash. Among those ages 16-20 at 0.08 percent BAC, male drivers were 52 times more likely that sober male drivers the same age to die in a single vehicle fatal crash (Zador, 1991). In 2008, of the 2,739 young drivers ages 15 to 20 years that were killed in motor vehicle crashes, 694 (25 percent) had a blood alcohol concentration (BAC) of .08 g/dL or higher (NCSA, 2009). According to 2009 survey data, about 3.8 percent of 16-year-olds, 8.7 percent of 17-year-olds, 14.1 percent of 18-year-olds, 17.5 percent of 19-year-olds, and 18.7 percent of 20-year-olds reported driving under the influence of alcohol in the past year (SAMHSA, 2010).
Unintentional and Intentional Injuries and Other Trauma
As shown in Figure E.9, homicide and suicide follow motor vehicle crashes as the second and third leading causes of death among teenagers. In 2006, 3,147 young people aged 12-20 died from homicide and 2,220 died from suicide (CDC 2009a). In addition, 2,332 individuals aged 16-20 died from unintentional injuries other than motor vehicle crashes, such as poisoning, drowning, falls, burns, etc. (CDC, 2009a).
At present, it is unclear how many of these deaths are alcohol-related. One study (Smith et al., 1999) estimated that for all ages combined, nearly a third (31.5 percent) of homicides and almost a quarter (22.7 percent) of suicides were alcohol attributable; they occurred when the decedent had a blood alcohol concentration of 0.10 g/dL or greater. Another study of deaths among those under 21 reported that 12 percent of male suicides and 8 percent of female suicides were alcohol related (Levy et al., 1999).
Individuals under the age of 21 commit 45 percent of rapes, 44 percent of robberies, and 37 percent of other assaults (Levy et al., 1999); for the population as a whole, an estimated 50 percent of violent crime is related to alcohol use by the perpetrator (Harwood et al., 1998). The degree to which violent crimes committed by those under 21 are alcohol related is yet unknown.
Underage Drinking Increases the Likelihood of Risky Sexual Activity
According to the Surgeon General (U.S. Department of Health and Human Services [HHS], 2007), underage drinking plays a significant role in risky sexual behavior, including unwanted, unintended, and unprotected sexual activity, and sex with multiple partners. Such behavior increases the risk of unplanned pregnancy and sexually transmitted diseases (STDs), including infection with HIV, the virus that causes AIDS (Cooper and Orcutt, 1997). When pregnancies occur, underage drinking may result in fetal alcohol spectrum disorders, including fetal alcohol syndrome, which is a leading cause of mental retardation (Jones et al., 1973, Warren and Bast, 1988, Stratton, et al., 1996). Underage drinking by both victim and assailant also increases the risk of physical and sexual assault (Hingson et al., 2005; Nolen-Hoeksema, 2004). These risks are of particular concern, given the increasing rates of heavy drinking among underage females discussed earlier.
Early Initiation of Alcohol Use Increases the Risk of Alcohol Dependence Later in Life
Early-onset alcohol use ( 14 years) is associated with alcohol problems later in life. Grant and Dawson (1997) found that more than 40 percent of persons who initiated drinking before age 13 were classified with alcohol dependence at some time in their lives. By contrast, rates of alcohol dependence among those who started drinking at age 17 or 18 were 24.5 percent and 16.6 percent, respectively (Figure E.10). Only 10-11 percent who started at age 21 or older met the criteria.
Similar effects were found for later involvement in alcohol-related traffic crashes. Adults who began drinking at age 14 were three times as likely to report driving after drinking too much, and four times as likely to crash, as those who began after turning 21.
Adverse Effects on Normal Brain Development Are a Potential Long-Term Risk of Underage Alcohol Consumption
Research suggests that early heavy alcohol use may affect the physical development and functioning of the brain. Some cross-sectional neurological studies suggest decreased ability among heavy alcohol users in planning, executive function, memory, spatial operation, and attention. These deficits, in turn, may put alcohol-dependent adolescents at risk for falling farther behind in school, putting them at an even greater disadvantage relative to nonusers (Brown et al., 2000). Some of these cross-sectional findings have been supported by recent longitudinal analyses (Squeglia et al. 2009).
Underage Drinking Affects Academic Performance
It has been know for decades that underage drinking affects academic performance. According to the 2009 Youth Risk Behavior Surveillance System, of the 1 million high school students who binged at least five times per month, one-third did so on school property. These students were three times more likely to report earning mostly Ds and Fs on their report cards (CDC, 2010).
College Drinking Has Numerous Adverse Consequences
Rates of negative alcohol-related consequences among underage college students are very high (Figure E.11). These include unintentional death, including motor vehicle crashes; unintentional injury; physical assault; and sexual assault or date rapes. Campus alcohol use also contributes to unsafe sexual practices, academic problems, and vandalism.
THE NATIONAL EFFORT TO REDUCE UNDERAGE DRINKINGFEDERAL RESPONSES
The scope and impact of underage drinking have encouraged an aggressive, coordinated response from the Federal Government. Among the earliest of these responses was the National Minimum Drinking Age Act of 1984, which reduced Federal transportation funding to States not prohibiting alcohol “purchase and public possession” for those under age 21. All States eventually raised or restored their legal ages for alcohol purchase and public possession to 21 years. NHTSA estimates that this single law has saved an estimated 800 to 1,000 young lives per year since it went into effect
As national concern over underage drinking grew, Congress appropriated funds for a study by The National Academies to “review existing Federal, State, and nongovernmental programs, including media-based programs, designed to change the attitudes and health behaviors of youth.” The report, issued in 2004 by the National Research Council (NRC) and the Institute of Medicine (IOM), became a guiding document for coordinated underage drinking prevention efforts at the Federal, State, and local levels. Its title,
Reducing Underage Drinking: A Collective Responsibility (NRC, IOM, 2004), was also its overriding message. The report called for coordinated action at the Federal, State, and local levels, including colleges and universities. Many of the reports recommendations focused on strategies to reduce youth access to alcohol.