You have probably heard of people who drink wine (particularly red) because they believe it is healthy for the heart. The source of this belief comes from a study done 25 years ago where it was found that people in France and Spain were healthier than Americans, and this was attributed to the fact that they drank wine with their daily meals. Thus, since that study wine has begun to be seen as a better, healthier option than alcoholic beverages such as beer and hard liquors (and possibly some non-alcoholic beverages as well).
So what about red wine made it healthy? Well, its polyphenolic compounds (specifically resveratrol), were seen to have antioxidant and anti-inflammatory properties. While this is true, polyphenols are not just found in red wine, they are also found in grape juice, beer, liquors, and virtually foods derived from plants. Many studies have also found that moderate consumption* of any alcoholic beverage reduces the risk of heart attacks, ischemic strokes, type 2 diabetes, gallstones, and cognitive impairment.
There is also the issue of controlling factors. For example, there is good evidence that wine drinkers in general have healthier habits and diets then those who consume beer and/or hard liquors. They have better diets and are less likely to smoke or be obese. In regards to the French paradox, it must be noted that the French tend to consume less calories and be more active than Americans, so this, and not wine, might be a reason why they are healthier.
*Moderate intake is no more than one drink a day for women and two drinks for men. People over 65 should drink less. A standard drink is 5 ounces of wine, 12 ounces of beer, or a relatively modest 1.5 ounces of 80-proof liquor, which all average about 14 grams of pure alcohol.