A seemingly healthy aging population may be facing an overlooked concern, according to new research. Affluent people over the age of 50 that are otherwise in good health are weirdly heavy drinkers.

Researchers examined data from the English Longitudinal Survey of Aging (ELSA), where participants answered questions about their daily lifestyle including diet, alcohol consumption, depression and loneliness, and whether they are caretakers.

The team paid particular attention to “higher risk drinking,” which was defined as over 50 units of alcohol per week for men and more than 35 units of alcohol per week for women. A unit was not defined as a standard serving of alcohol though — apparently, a small glass of wine or beer counted as about two or three units, so “high risk drinking” was defined as about 17 to 25 glasses a week for men and 12 to 17 a week for women.

The type of people who were drinking the most was somewhat surprising. According to the study, the heaviest drinkers tended to be those in good health, with the most education, a high income, and a socially active lifestyle. Depression also had nothing to do with it; there was no correlation between heavy drinking and loneliness or depression.

“Our findings suggest that harmful drinking in later life is more prevalent among people who exhibit a lifestyle associated with affluence and with a ‘successful’ ageing process,” the researchers wrote in the study. “Harmful drinking may then be a hidden health and social problem in otherwise successful older people.”

This finding seems odd, since highly educated people should be the ones most aware of the risks of heavy drinking. They almost certainly see public health messages about the harmful effects, too. Psychologist Debra Serani suggests, however, that affluent individuals may feel immune to the effects of drinking because of their social status. “I tend to think affluent people have more entitlement issues,” she told Forbes, “and as such, believe the public campaigns or health warnings don’t apply to them. At all.”

The study also found that having caring responsibilities decreased the risk of heavy drinking, and that smoking is positively associated with higher levels of drinking. Men’s drinking peaked in their 60s, dropping off after that, and women’s peaked at age 50.

Whatever the cause, this trend could be a problem. The suggested safe level of drinking is one unit per day for women and two for men. There are benefits to certain kinds of light drinking, but none documented for heavy drinking.

This information could be useful for designing future preventative interventions, according to the study.

Source: Iparraguirre J. Socioeconomic determinants of risk of harmful alcohol drinking among people aged 50 or over in England. BMJ Open. 2015.