It's interesting how drinking alcohol seems to have a J-curve for health effects. Light drinkers seem to do the best, but heavy drinkers do the worst of all groups (also see earlier posts). This research (published this week in the journal Stroke) shows that drinking more than 2 drinks a day in middle age is a bigger risk factor (double the risk) for a stroke between the ages of 60 to 75 years than high blood pressure, diabetes, or genetics. And once again, looking at the study one can see that nondrinkers had a small increased risk for stroke vs very light drinkers. From Science Daily:
Drinking more than two alcoholic beverages a day in middle-age raised stroke risks more than traditional factors such as high blood pressure and diabetes. Heavy drinking in mid-life was linked to having a stroke about five years earlier in life irrespective of genetic and early-life factors.
In a study of 11,644 middle-aged Swedish twins who were followed for 43 years, researchers compared the effects of an average of more than two drinks daily ("heavy drinking") to less than half a drink daily ("light drinking").
The study showed that: - Heavy drinkers had about a 34 percent higher risk of stroke compared to light drinkers. - Mid-life heavy drinkers (in their 50s and 60s) were likely to have a stroke five years earlier in life irrespective of genetic and early-life factors. - Heavy drinkers had increased stroke risk in their mid-life compared to well-known risk factors like high blood pressure and diabetes. - At around age 75, blood pressure and diabetes appeared to take over as one of the main influences on having a stroke.
Researchers analyzed results from the Swedish Twin Registry of same-sex twins who answered questionnaires in 1967-70. All twins were under age 60 at the start. By 2010, the registry yielded 43 years of follow-up, including hospital discharge and cause of death data. ... Almost 30 percent of participants had a stroke. They were categorized as light, moderate, heavy or non-drinkers based on the questionnaires.
Among identical twin pairs, siblings who had a stroke drank more than their siblings who hadn't had a stroke, suggesting that mid-life drinking raises stroke risks regardless of genetics and early lifestyle.
The study is consistent with the American Heart Association's recommended limit of two drinks a day for men and one for women. That's about 8 ounces of wine (two drinks) for a man and 4 ounces (one drink) for a woman. Regular heavy drinking of any kind of alcohol can raise blood pressure and cause heart failure or irregular heartbeats over time with repeated drinking, in addition to stroke and other risks.