Amino acids (BCAA): does it break a fast?

Strictly, yes, they break the fast: they are the building blocks of protein, provide about 4 kcal per gram (even if many labels say 0) and leucine stimulates insulin. There is no good evidence they add anything if you already eat enough protein in your window.

Approximate energy: ≈20–40 kcal

More questions

• Water (still or sparkling)
• Black coffee
• Yerba mate (unsweetened)
• Tea and herbal infusions, unsweetened
• Sweeteners (sucralose, stevia)
• Mate, coffee or tea with sugar or honey
• A splash of milk in your coffee
• Latte, flat white or cappuccino

General information; not a substitute for a health professional.