Even Light Drinking Poses Risk to Heart

Cardiovascular health may improve for light and moderate drinkers who cut back on alcohol

(RxWiki News) While heavy drinking has clearly been shown to be bad for overall health, much research has shown that moderate alcohol consumption can offer benefits for the heart. A new study, however, may change that notion.

For decades, research has shown that death rates from heart attack or stroke were lower for moderate drinkers than for those who never drank or quit drinking.

Scientists have recently found, however, that any reduction in alcohol consumption — for light, moderate or heavy imbibers — may provide heart health benefits.

"Limit drinking to improve heart health."

Juan P. Casas, PhD, professor of epidemiology at the London School of Hygiene & Tropical Medicine and the University of Pennsylvania in Philadelphia, collaborated on this investigation, reviewing data from 50 studies concerning cardiovascular health and drinking habits.

The studies represented about 262,000 people, including 20,259 coronary heart disease patients and more than 10,000 who had stoke events.

Dr. Casas and team categorized patients as “never drinkers” (fewer than 12 alcoholic drinks in their lifetime), infrequent drinkers (more than 12 drinks in a lifetime but less than 12 in any one year), former drinkers (not currently drinking but at one point drank more than 12 drinks a year), light drinkers (three or fewer per week), moderate drinkers (three to seven drinks per week for women and three to fourteen drinks per week for men) and heavy drinkers (more than seven drinks per week for women and more than 14 for men).

These researchers discovered that those with a genetic variant — called alcohol dehydrogenase 1B — linked to lower alcohol consumption generally had a better cardiovascular profile than those without this variant.

In those with the genetic variant, alcohol breaks down in the body differently, causing nausea, flushing or other negative effects. These unpleasant symptoms in turn lead people to drink less.

Compared to those without this different gene, people carrying the variant drank 17 percent fewer units of alcohol per week. These patients were also less likely to binge drink, and they had high rates of not drinking altogether.

On average, those with the gene variant had a 10 percent lower risk of having heart disease. In addition, they had lower systolic blood pressure (an average reduction of 0.88 mm HG) and a lower body mass index (an average reduction of 0.17 kg/m2). Systolic pressure is the top number in a blood pressure reading and indicates the amount of pressure on the arteries as the heart beats. Body mass index (BMI) is a measure of body fat based on height and weight.

This study suggests that even light and moderate drinkers may boost heart health by limiting alcohol consumption, according to the authors.

"While the damaging effects of heavy alcohol consumption on the heart are well-established, for the last few decades we've often heard reports of the potential health benefits of light-to-moderate drinking,” said Dr. Casas in a press release.

“In our study, we saw a link between a reduced consumption of alcohol and improved cardiovascular health, regardless of whether the individual was a light, moderate or heavy drinker," Dr. Casas said. "Assuming the association is causal, it appears that even if you're a light drinker, reducing your alcohol consumption could be beneficial for your heart.”

This study was published July 10 in BMJ. Funding was provided by the British Heart Foundation and the Medical Research Council.

Review Date: 
July 11, 2014