Alcohol Intake Peaks at Age 25, But Continues into Old Age

But the researchers also found that, although younger guys drank the largest quantities of alcohol, it was older men who drank the most often, "with lots of men drinking on a daily basis in later life," said lead researcher Annie Britton, a senior lecturer of epidemiology at University College London.

It's concerning that many older men report drinking daily, she said. It could mean that they are becoming dependent on alcohol, she told Live Science. What's more, alcohol can interfere with some medications that are commonly used by older people, such as drugs for blood pressure and pain relief. [How 8 Common Medications Interact with Alcohol]

For the new findings, the researchers pulled data from nine previous studies that included a total of nearly 60,000 people and spanned a 34-year period, from 1979 to 2013. The new study is the first to pool extensive data on drinking behaviors from such a large group of people over a long period of time, according to the findings, published online today (March 5) in the journal BMC Medicine.

People in different age groups had different drinking habits, the researchers found. Teenagers and people in their 20s tended to drink large amounts of alcohol, but only once or twice a week. At age 25, men drank about 10 drinks weekly, on average, whereas women drank about four or five drinks weekly on average, they found.

Women's intake was on average less than men's — a finding that was "no surprise," Britton said. Women in the study were also more likely than men to say they drank only once a month, or on special occasions, the researchers found.

People drank less as they reached middle age. By age 60, men reported drinking an average of three to five drinks of beer a week. By age 70, women reported drinking about one to two drinks a week.

The researchers also looked at drinking frequency, or how often people drank. Drinking frequency increased during middle age, meaning that people — especially men — tended to drink daily or on most days of the week. But frequent drinking declined in very old age, the study showed.

The new study didn't explore the reasons behind these drinking habits, but other studies show that people generally reduce their alcohol intake as they age because of health concerns, weight issues or because they attend fewer social events, Britton said.

"Other people told us they increased their consumption to help them sleep, because they were depressed [or] lost a loved one," Britton said.

Though the study only looks at people in the United Kingdom, it can help researchers identify what groups of people may be putting their health at risk, she said. 

Still, "These findings in the U.K. are very similar to the U.S.," said Dr. Mark Willenbring, the former director of the Division of Treatment and Recovery Research of the National Institute on Alcohol Abuse and Alcoholism at the National Institutes of Health (NIH) in Bethesda, Maryland. He is now the founder and CEO of the addiction treatment center Alltyr in St. Paul, Minnesota.

However, the United States likely has more nondrinkers than the United Kingdom, he said. The new study found that less than 10 percent of people in the United Kingdom study were abstinent until age 90, when abstinence rose to above 20 percent, the researchers said.

"There's a lot more abstinence in the U.S.," Willenbring said. Middle-aged adults in the United States also probably drink less frequently than those in the United Kingdom, he noted.

Follow Laura Geggel on Twitter @LauraGeggel. Follow Live Science @livescience, Facebook & Google+. Original article on Live Science.