Alcohol increases blood levels of the hormone renin, which causes the blood vessels to constrict. This means that they get smaller in diameter. Renin also decreases how much fluid the body eliminates as urine. This combination of higher fluid levels in the body and smaller blood vessels increases blood pressure .
Moderate alcohol consumption is thought to be heart healthy, but a new study suggests that the truth is more complicated.
Even moderate alcohol consumption appears to raise the risk of high blood pressure.
Drinking alcohol, even in moderation, may increase your risk of developing high blood pressure, say researchers. Yes, this is the same “moderate” that we’ve been told many times before is heart healthy. While earlier research has suggested that light and moderate alcohol consumption reduces the risk of dying from cardiovascular disease, a new study has a different finding. “This study certainly adds a twist to the notion that moderate alcohol consumption is beneficial for cardiovascular health,” said Dr. Gregory Marcus, director of clinical research, Division of Cardiology, at the University of California, San Francisco, who was not involved in the study.

Moderate drinking not so heart healthy

The new study was presented today at the American College of Cardiology’s 68th Annual Scientific Session. It included data from 17,059 U.S. adults who took part in the National Health and Nutrition Examination Survey (NHANES)Trusted Source between 1988 and 1994. People in the study reported their drinking behavior on several questionnaires. Study staff also measured participants’ blood pressure at home or at a mobile examination center. Researchers studied over 17,000 people and found those who consumed 7 to 13 drinks of alcohol per week were 53 percent more likely to have stage 1 hypertension, compared to nondrinkers. Heavy drinkers — more than 14 drinks per week —were 69 percent more likely to have stage 1 hypertension than nondrinkers. One standard drink contains about 0.6 fluid ounces of pure alcohol. The researchers found similar results for both men and women, although the available study abstract doesn’t provide separate data for them. Study author Dr. Amer Aladin, a cardiology fellow at Wake Forest Baptist Health, told Healthline they plan to do additional tests of the gender differences in the future. The researchers also took into account other risk factors for high blood pressure, such as age, race, and income.

Many factors drive blood pressure

Marcus, a cardiologist, said he “doesn’t think it’s surprising that even moderate alcohol consumption is sufficient to raise the blood pressure.” But he pointed out that this is an observational study, so it can’t show for certain the health benefits — or harms — of moderate drinking. For that, you’d need a randomized controlled trial, in which groups of people are assigned to drink a certain amount of alcohol each day for months or years. (There’s a study many people would love to join.) Marcus said the results could also be thrown off by “other factors that tend to travel with individuals who are able to stick to a routine and avoid excess.” For example, people who drink lightly or abstain may also tend to eat healthy, exercise regularly, and get enough sleep — all of which can lower their blood pressure. Grayver said the type of alcohol that people drink could also make a difference. Red wine, for instance, is thought to have anti-inflammatory effects on the body, which may also impact heart health. And what you eat with your glass of beer or wine or shot of whiskey can affect your blood pressure, too. “All of the pretzels, peanuts, and other snacks that go along with alcohol consumption have a significant amount of salt in them,” said Grayver. “That in itself could be driving the hypertension.” Even news stories that talk about the heart benefits of alcohol may play a part. “It is possible that once someone receives a diagnosis of hypertension, they may then be incentivized to drink alcohol in moderate amounts,” said Marcus. In a 2015 study, Marcus and his colleagues found that people who believed that alcohol is heart healthy were more likely to drink more, compared to those who thought otherwise.

The big picture of heart health

So what does the new study mean for your blood pressure and drinking preferences? Marcus said “the evidence is growing that even moderate alcohol consumption may, in fact, not be as heart healthy as we previously believed.” There are also other health risks to keep in mind. Marcus said one that is “underappreciated” is the link between alcohol — even moderate amounts — and an increased risk of atrial fibrillation, a quivering or irregular heartbeat. including head and neck, breast, and colon cancers. Grayver, though, emphasized that “there should not be a cookie-cutter approach to every single patient regarding their alcohol consumption.” The first step is to check your blood pressure. Your doctor should do this as part of your regular office visits. You can also check your blood pressure at home. If your blood pressure is borderline or high, talk to your doctor about your options. This often means looking at the big picture, not just how much you drink. “If a patient has significant risk factors for hypertension besides the alcohol consumption, I would definitely err on the side of decreasing their alcohol consumption to either none or truly mild consumption.”