(MNN) - We are a species that loves our fermented grapes. We’ve been making and drinking wine since 6000 B.C. Even as far back as 2,000 years ago there were wine bars on every street in Roman cities. In 2014, Americans consumed an estimated 893 million gallons of wine. That’s a lot of quaffing.

But is the veneration of vino a good thing? We wine-sipping tipplers do a collective happy dance whenever a new study is published promoting the health benefits of wine in moderate consumption … as we plug our ears and hum loudly when other studies come out highlighting the health risks.

So with that in mind, here’s a look at all the different things science says about what can happen at wine o’clock — the good, the bad and the ugly all in their fermented glory.

To start things off, just what is moderate consumption? A standard drink is equal to 14.0 grams (0.6 ounces) of pure alcohol, which generally equates to 5 ounces of wine (and is roughly equivalent to 1.5 ounces of liquor or 12 ounces of beer, though variations in strength will throw that off). According to the Dietary Guidelines for Americans, moderate alcohol consumption means having up to one drink per day for women and up to two drinks per day for men. Most studies quantify amounts used in research.

Boosts antioxidants

Much of the research interest in wine has to do with antioxidants. Known as polyphenols, and especially flavonoids and resveratrol, these antioxidants are believed to work to protect the cells and tissues against harm that can lead to various diseases like cancer and heart disease. Wine, especially red wine, is loaded with them.

May limit atherosclerosis

According to the American Heart Association (AHA), a number of studies suggest that the polyphenolic compounds in red wine may play an active role in limiting the start and progression of atherosclerosis, a disease in which plaque builds up inside the arteries.

Increases 'good' cholesterol

Having one to two drinks per day has been shown to boost HDL cholesterol by about 12 percent, reports the AHA. This “good” cholesterol can help clean up the bad low-density lipoprotein (LDL) cholesterol from the system and lessen the amount of material available to clog up the arteries.

Decreases risk of heart disease

When the data from 51 epidemiological studies were analyzed together for this AHA report, they revealed that the risk of coronary heart disease decreased by approximately 20 percent when up to two alcoholic drinks were consumed per day.

Lessens risk of heart attack

Meanwhile, in the comprehensive longitudinal study known as the Health Professionals Follow-Up Study, 38,077 male health professionals who were free of heart disease were observed over the course of 12 years. Among the crew, drinking one to two drinks per day, three to four days per week decreased the risk of having a heart attack by as much as 32 percent.