We’ve all heard that a glass of wine, especially red wine, is heart-healthy. In fact, wine, like extra virgin olive oil, is featured prominently in the Mediterranean diet, which is considered the gold standard for how to eat to reduce the risk for heart disease. However, newer research suggests that the relationship between wine (and alcohol consumption in general) and cardiovascular biomarkers is more nuanced.

Since alcohol dependency is a real threat whenever you enjoy an adult beverage, experts are providing more specifics around how wine can help your heart—as well as how it can harm it. The heart-health benefits of vino are only associated with low to moderate intake (no more than 1 drink per day for women and 2 for men), and with the threat of dependency and adverse health outcomes, health professionals don’t recommend that you start drinking if you are an abstainer. (Related: Dangerous Side Effects of Drinking Too Much Wine, Says Science.)

“It’s unclear whether red wine is directly associated with this benefit or whether other factors are at play,” said Dr. Robert Kloner, chief science officer and director of cardiovascular research at Huntington Medical Research Institutes and a professor of medicine at the University of Southern California in an American Heart Association press release. “It might be that wine drinkers are more likely to have a healthier lifestyle and a healthier diet such as the Mediterranean diet, which is known to be cardioprotective,” he added.

Here’s everything you need to know about wine and your heart. Read on, and for more on how to eat healthy, don’t miss Eating Habits to Lose Abdominal Fat As You Age, Say Dietitians.

One of the ways low to moderate wine drinking heart health is by boosting HDL (“good”) cholesterol levels. Light to moderate drinking can raise good HDL cholesterol. Red wine is thought to be particularly beneficial as it can boost HDL while its polyphenols have been linked in some studies to help lower harmful, small dense LDL (“bad”) particles that are known to be drivers of coronary artery disease. In one study reported in the journal Circulation, 14 subjects participated in an alcohol trial, keeping all other dietary and lifestyle factors constant. The results found that daily moderate alcohol intake increased HDL cholesterol by an average of 18%, compared to when the subjects abstained from alcohol.

Platelets are a type of blood cell that form clots by sticking together. When your platelets are stickier, it raises the risk of forming a blood clot that can travel to your heart and cause a heart attack or to your brain where it can lead to a stroke.

Studies show that light or moderate wine drinking can reduce platelet aggregation and coagulation, reducing the risk for heart attacks and strokes. In a laboratory study reported in the European Journal of Internal Medicine, researchers combined platelets with red wine, extracted red wine polyphenols or non-wine alcohol. They then evaluated the impact on platelet aggregation. The red wine and isolated red wine polyphenols both inhibited aggregation dose-dependently while non-wine alcohol did not inhibit aggregation.

Several studies show that drinking more wine than what’s recommended may negatively impact your heartbeat, increasing the risk for arrhythmias. Alcohol intake can up your risk for atrial fibrillation, atrial flutter, several types of tachycardia, and other arrhythmias. In the famous Framingham Heart Study, researchers reported in the American Journal of Cardiology that alcohol consumption of more than 36 grams per day increased the risk of atrial fibrillation by 34%, after adjusting for potential confounders. A serving of alcohol (5 ounces of wine) equals ~14 grams of ethanol. If you’re not sure whether you’re overdoing it on the vino, check out these 5 Subtle Signs You’re Drinking Too Much Wine.

No cardiologist is going to suggest that you toast to your heart’s health because long-term drinking elevates your blood pressure and can increase the risk for hypertension, peripheral vascular disease, and stroke. According to a review study reported in the peer-reviewed journal Addiction, drinking alcohol causes increased blood pressure in a dose-dependent fashion. When 50 grams per day of ethanol is consumed, the risk for hypertension is increased by 70% and with 100 grams of ethanol per day the risk for hypertension increased by 250%. (A 5-ounce serving of wine provides ~14 grams of ethanol.)

Alcohol abuse has a toxic effect on your organs, including your heart. Alcoholic cardiomyopathy weakens and thins the heart muscle so it can no longer pump blood efficiently and it leads to heart failure. According to a review in the World Journal of Cardiology, one of the causes of this condition is excessive alcohol consumption. The only way to treat this disease is to avoid alcohol altogether and in many cases, if the disease has progressed too far, the damage to the heart muscle is irreversible.6254a4d1642c605c54bf1cab17d50f1e

Red wine is often heralded as a heart-healthy choice, but it’s not that simple. Low to moderate intakes of red wine may provide heart health benefits, binging or drinking more than what public health officials recommend can be harmful to your heart. For more on this popular beverage, learn about the People Who Should Never Drink Wine, According to an Expert.