Sugar Content Some brands comprise significant fructose corn syrup, although other brands contain cane sugar or just sugar from the ingredients. Any time you add an alcoholic component, like gin, to produce a gin and tonic cocktail, the calorie count can increase to 200 calories or more for each serving. https://tonic-water-with-quinine44433.webbuzzfeed.com/29350051/detailed-notes-on-tonic-water-price