Red wine has long been discussed in the medical sphere, with studies about health benefits going back generations. One specialist says it lowers cholesterol, another announces that it improves heart health, and suddenly the smart people at universities around the globe are discovering that feeding red wine to mice makes them happy. You've heard Mary Poppins say that "a spoonful of sugar helps the medicine go down," but does it help a glass of red wine go down, too? While dry red wines contain very low amounts of sugar, sweeter variations might surprise you with just how much sugar it holds.

Any wine, from a Cabernet to a Pinot Grigio, will contain some amount of sugar. After all -- if there was no sugar, there would be no wine. Grapes naturally contain sugar, but the fermentation process (which turns grape juice into an alcoholic beverage) dissolves most of those sugars. During fermentation, winemakers add yeast to the barrel of grape juice. The yeast eats up the sugar, converting it to alcohol, but sometimes sugar is still left behind. This residual sugar can fluctuate depending on when the yeast is stopped, a decision that comes from whatever kind of wine the winemaker is aiming to create.

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Varying levels of fermentation mean varying levels of residual sugar. Winemakers aren't required to place nutritional labels on their product (such as sugar levels) but an easy rule of thumb is that the sweeter the wine type, the more sugar it contains. Bone-dry wines such as Cabernet Sauvignon and Tempranillo contain less than one gram of residual sugar per glass, while dry wines such as Merlot, Shiraz, and Pinot Noir contain about two grams. A glass of Alta Vista Classic Malbec, a dry red wine, will set you up with 2.8 grams of residual sugar.

Off-dry red wines -- such as a Malbec or Zinfandel -- contain about three to five grams of residual sugar. That glass of Gnarly Head Old Vine Zinfandel sits moderately dry at 3.4 grams of sugar. Once you get into the sweet and very sweet red wines, you're looking at much more sugar. A Lambrusco, Rosso Dolce, or California Red will contain about 13 grams of residual sugar per glass. Dessert wines that fall into the very sweet category, such as a Shiraz, Port, or Vin Santo Rosso, contain upwards of 15 grams of sugar per glass, even though these are traditionally served in smaller portions than a standard glass of wine. If you're looking to stay away from sugar but still enjoy a good glass of red wine, stick with the cabs and the pinots, and definitely don't try adding sweetened condensed milk, no matter how good it looks.

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