Thank you. I hope this is not a silly question.
Although wine snobs may claim they can taste the difference between cheap and expensive wines, the truth is that delicious wines can be purchased at a wide range of prices. Many different factors, such as land price, farming practices, the fermentation and aging processes, and even the brand name can affect how much wine costs — but none of these are directly related to adding sugar.
Sugar serves several purposes in the complex process of winemaking. First, sugar is what yeast metabolizes into alcohol to make wine alcoholic. The riper grapes are, the higher sugar content they have, and the more alcohol the wine will eventually contain. If grapes are less ripe, sugar may be added before fermentation so the final product will be more alcoholic. In dry wines, all the sugar is allowed to ferment into alcohol, whereas sweet wines have more residual sugar. Sugar can also be added after the fermentation process to change the sweetness level of the wine. In some cases, risking losing the grape crop by letting the fruit ripen for longer on the vine or complicating the process by using sugar for flavor or a secondary fermentation may increase the price of wine.
However, what determines the calorie level of your wine is not how much it costs, but a combination of its sugar content and, most importantly, the amount of alcohol in it. A six ounce-serving of wine can contain anywhere from around 107 to 275 calories depending on whether it is red or white, dry or sweet, and light or heavy alcohol. As alcohol contains close to twice as many carbs as sugar, heavier wines tend to be more caloric. If you’re looking for the wine with the smallest effect on your waistline, you’re best off choosing a light, dry white wine. Since you said you prefer red, however, try looking for a light, dry wine such as a Pinot Noir, Cabernet Sauvignon, or Syrah — not only do these wines tend to have fewer calories, but they also contain different minerals and antioxidants which, when consumed in moderation, may be beneficial for heart health.