Does Sparkling water break a fast?
Does not break a fast
Sparkling water does not break a fast when used as directed — its calorie and insulin impact is negligible for standard fasting goals.
Calories
0 kcal (plain carbonated water, no flavourings or sweeteners)
Why — the calorie and insulin logic
Plain carbonated water — water with CO₂ — contains zero calories. The carbonation has no effect on insulin or digestive enzyme secretion. It can help with hunger and hydration just as still water does.
Does it depend on your fasting goal?
Safe for all fasting goals. Be careful with flavoured sparkling waters: many contain citric acid or natural flavourings that may theoretically stimulate digestive enzymes, though the practical effect is minimal. Sweetened sparkling drinks (like tonic water) will break a fast.
Frequently asked questions
- Does sparkling water break intermittent fasting?
- No. Plain sparkling water has zero calories and does not affect insulin. Choose unflavoured, unsweetened varieties to stay completely fast-safe.