Espresso has 9 kcal per 100 g — but a 30 ml shot is only 2–3 kcal. The caffeine concentration is ~5x stronger than drip coffee per ml, but the calories stay negligible until milk or sugar joins.
How should I track Espresso?
Espresso is a good source of magnesium. Liquid calories from Espresso 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.