Grape juice has 37 kcal and 0 g sugar per 100 g. It is among the sweetest 100% fruit juices. A 250 ml glass packs ~0 g sugar. The natural sugars from juice raise glucose nearly as fast as soda; whole grapes feed slower thanks to fiber.
How should I track Grapefruit juice, white, canned or bottled, unsweetened?
Liquid calories from Grapefruit juice, white, canned or bottled, unsweetened are easy to overlook because drinks do not trigger the same fullness signals as solid food. A meta-analysis (Wehling & Lusher, Am J Clin Nutr 2021) confirmed that people underreport beverage intake more than solid food. Most people pour 30–50% more than the label serving size without realizing it. Use a kitchen scale to weigh your glass or bottle once — you will know your exact pour going forward. This one calibration step can save you from hundreds of untracked calories per week.