We've all heard about the heart-healthy perks of enjoying red wine in moderation. But a certain segment of the population might not be able to reap those benefits -- according to new research, about 7 percent of people might actually have a physical intolerance to alcohol.
A new study in the German peer-reviewed science journal Deutsches Arzteblatt International shows that "wine intolerance" may affect 8.9 percent of women and 5.2 percent of men.
To conduct the study, German researchers from the Johannes Gutenberg University Mainz sent out questionnaires to 4,000 people between ages 20 and 69. Of those people, 948 responded.
The researchers acknowledged that the results of the study may be "limited" because not everyone completed the questionnaires. But they explained that even if none of the non-respondents had symptoms of wine intolerance, "the resulting prevalence of 1.7% (68 out of 4000 people) can be considered to be the lower limit. Thus, the prevalence of wine intolerance is much higher than previously thought and occurs at a similar rate as other common food intolerances."
Red wine seemed to be associated with the greatest number of allergy-like symptoms among the people in the study, researchers reported, and the most common reactions included having nasal congestion, feeling flushed or feeling itchy.
The researchers noted, too, that rates of wine intolerance may also be higher than the study suggests, since they did not ask people about headache symptoms after drinking wine.
Researchers also found that people who reported some sort of symptom after drinking wine were also more likely to have intolerances to other kinds of foods.
In 2010, MSNBC reported on a study from the University of Southern Denmark that suggests as many as 8 percent of people in the world have cold symptoms as a result of drinking wine -- and the symptoms may be a result of a kind of protein in wine from fermentation, called glycoproteins.
"I find that if I have one to two glasses of wine, my sinuses will get stuffed up," Christi Foist, a 32-year-old who lives in San Francisco, told MSNBC. "And if I don't drink enough water, I'll get the headache. I think it must be the sulfites or something else."
When the body can't break down alcohol toxins because it doesn't have the right enzymes to do so, it leads to alcohol intolerance, the Mayo Clinic reported. However, intolerance to specific kinds of alcohol -- like beer or wine -- may be from an intolerance to other ingredients in the beverage, like grains, sulfites or histamine, according to the Mayo Clinic.