Although men still drink more than women do, that difference is diminishing as alcohol consumption among women grows, a new U.S. study finds.

Data gathered in the annual National Survey on Drug Use and Health between 2002 and 2012, involving around 70,000 people each year, shows the difference between men and women in rates of alcohol consumption and alcohol-related harms has been diminishing, researchers say.

"We found that over that period of time, differences in measures such as current drinking, number of drinking days per month, reaching criteria for an alcohol use disorder, and driving under the influence of alcohol in the past year, all narrowed for females and males," says study lead author Dr. Aaron White.

Men still drink more, but that gender gap in alcohol consumption is shrinking, says White, senior scientific adviser to the director of the National Institute on Alcohol Abuse and Alcoholism.

Between 2002 and 2012, the percentage of women reporting they drank alcohol jumped from 44.9 percent to 48.3 percent, while the figure for men dropped from 57.4 percent to 56.1 percent, the researchers report in the journal Alcoholism: Clinical and Experimental Research.

The number of drinking days per month reported by women increased from 6.8 to 7.3 days, the study found, again decreasing slightly for men from 9.9 to 9.5 days.

"This study confirms what other recent reports have suggested about changing patterns of alcohol use by men and women in the U.S.," says National Institute on Alcohol Abuse and Alcoholism Director George F. Koob.

The findings are especially worrisome since women face greater risks of alcohol-related health impacts, including cardiovascular disease, cancer, liver inflammation and neurotoxicity, he points out.

The reasons for the increase in drinking among women are unclear, the researchers acknowledge, and don't seem linked to recent trends among women in employment, marital status or pregnancy, the researchers say.

One issue addressed by the study was binge-drinking, defined as consuming five or more drinks during a single occasion.

In the study's time period, the percentage of women age 18 to 25 not in college who reported binge-drinking increased significantly, from 29.1 percent to 32.6 percent, while decreasing among men in the same category, falling from 49.8 percent to 45.4 percent.