Marijuana Use in the U.S. Has Increased Since 2005, but Not Because of Legislation, Study Says

Majority of voters think legalizing marijuana would be better for society
Cannabis use has steadily increased since 2005 across the U.S. among people 18 and older. Ron Wurzer/Getty Images

American adults are smoking more pot, but increased cannabis use does not appear to be due to wider availability of legal marijuana, a new study shows.

Pot consumption among women almost doubled between 1984 and 2015, from 5.5 percent of adults to 10.6 percent; meanwhile, 14.7 percent more men are toking up in 2015 compared to 8.8% since 2000, according to the report from the Public Health Institute.

But researchers cautioned against assuming that relaxed laws governing recreational and medicinal pot are driving the trend.

"Results ...did not show significant increases in use related to medicinal marijuana legislation," lead investigator William Kerr said in a statement. "It appears that the passage of these policies reflects changing attitudes toward marijuana use, rather than the other way around."

Overall, 12.9 percent of adults have used marijuana in 2015, up from the 6.7 percent 10 years earlier, the study revealed. However, it did not find a significant intersection between higher rates of pot use and legislation, which has legalized medical marijuana in 29 states and permitted recreational smoking in eight states—Washington, Oregon, Colorado, California, Nevada, Alaska, Massachusetts and Maine—plus the District of Columbia.

The study also showed that people aged 50 to 59 are especially avid pot users, with these men increasing from 0.5 percent of the age group to 11.6 percent, an increase of 2,220 percent. Women went from 0.1 percent to 7.3 percent, a staggering 7,200 percent increase.

"These increases are the results of both age period cohort and period effects. People born before 1945 had very low lifetime rates of marijuana use," said Kerr, who is also a senior scientist at the Alcohol Research Group. Baby Boomers, however, have led the pot party.

They are not alone. A CBS News poll conducted in April found that 71 percent of Americans believed that the federal government should not prohibit marijuana sales, and 65 percent said that weed is less dangerous than other drugs. A Quinnipiac University poll also found that 60 percent of Americans believed use of marijuana should be made legal.

Despite widespread support, the Trump administration and GOP are committed to stopping efforts to legalize marijuana consumption. The House Rules Committee on September 7 blocked the Hinchey-Rohrabacher Amendment, which prohibited the Department of State from using federal money to enforce measures against states that approved medical marijuana.