While a daily tipple won’t harm your health, drinking to excess can harden your arteries, says recent research.

Knocking back a couple of cold ones (like these 6 acceptable post-workout beers) or enjoying a cocktail or two has been shown in the past to help with heart health, but going overboard daily—meaning more than one or two drinks a day—can increase the risk of high blood pressure, obesity, and stroke.

A recent study showed that heavy drinking may also stiffen the arterial walls, squeezing blood flow and increasing the risk of heart disease. Researchers analyzed the drinking habits of almost 4,000 U.K. residents over 25 years of age, and found that moderate drinking is linked with a reduced risk of heart disease, but heavy drinking—more than 3.9oz of pure alcohol per week—has the opposite effect.