Alcohol: The Heart’s Double-Edged Sword

In the wake of the National Institutes of Health deciding to withdraw funding for a study aimed at assessing moderate alcohol consumption and cardiovascular risk/benefit, I thought the timing could not be better to elaborate upon alcohol consumption and the heart.   I tell my patients that alcohol is a double-edged sword when it involves the heart. On the one hand, complete abstainers (or teetotalers), are at higher risk of heart disease than moderate drinkers. Yet on the other hand, too much alcohol causes a number of problems ranging from abnormal heart rhythms (such as atrial fibrillation) to enlarged hearts and heart failure. Clearly, a moderate amount of alcohol represents the “sweet spot” for keeping hearts healthy and enjoying alcohol’s protective effects  (see below). For women, that sweet spot is ~3-5 servings of alcohol each week (for men ~6-10 servings). One serving of alcohol consists of a 4-ounce glass of wine, a 12-ounce bottle of beer (or a pint of Guinness due to lower alcohol content) or a shot of your favorite spirits. Even though, any type of alcoholic beverage in moderation is protective to the heart, red wine and dark beer may offer a slight advantage due to the higher content of antioxidant polyphenols.

[Full disclosure….I’m a big fan of Guinness beer and Maker’s Mark bourbon].

Here are several heart health benefits of moderate alcohol consumption.

1. Raises HDL (the good cholesterol):  A high level of HDL (60 mg/dL or greater) is most protective to the heart when no major cardiovascular risk factor is present (cigarette smoking, high blood pressure, diabetes, high cholesterol); moderate drinking boosts HDL levels ~5-15% on average.
2. Reduces blood clotting:  Alcohol reduces clot buildup by inhibiting platelet aggregation.  However, excessive alcohol consumption (4 or more drinks daily) may increase the risk of serious bleeding, including a brain hemorrhage.
3. Reduces risk of Type 2 Diabetes:  Moderate alcohol consumption lowers fasting insulin and HbA1c concentrations in men and women at increased risk of diabetes.  In women, moderate alcohol intake  also improves insulin sensitivity.

Light drinkers (1-3 drinks per week) also derive health benefits; a new study out this week found that lifetime light drinkers had a reduced risk of cancer.  This extends prior work finding that heavy drinkers exhibited increased risk of several cancers including head and neck, breast, esophageal, liver and colorectal cancer.

Michael Miller, MD is Professor of Cardiovascular Medicine at the University of Maryland School of Medicine in Baltimore, Maryland USA where he takes care of patients, conducts original research and teaches at the medical school.  His bestselling book “Heal Your Heart: The Positive Emotions Prescription to Prevent & Reverse Heart Disease” is also Amazon’s #1 Rated book in Heart Disease.