Does a matcha latte break a fast?

Yes. Milk adds calories, protein and lactose, and many café versions use sweetened powder. Keep lattes for your eating window.

How much caffeine is in matcha?

Roughly 19 to 44 mg per gram depending on the tea, so a 1 g serving has about 20 to 45 mg and a teaspoon about 40 to 90 mg.

Does matcha break autophagy?

Plain matcha is unlikely to. It has only a few calories, and lab studies link its main catechin, EGCG, to autophagy, though there is no human evidence that matcha boosts it during a fast.

Can I sweeten matcha while fasting?

A few drops of stevia or monk fruit keep it fast-friendly. Sugar, honey and syrups end the fast.

Does Matcha Break a Fast? No

Reviewed by the FastTrack team · Updated June 2026

Short answer: No

Plain matcha does not break a fast for most goals. A teaspoon of powder (about 2 g) whisked with water has roughly 5 to 10 calories, too little to raise insulin. A matcha latte made with milk and sweetened powder is a different drink, and it does break a fast.

Calories	~5-10 kcal per tsp (plain)
Breaks a weight-loss fast?	No
Breaks ketosis?	No
Breaks autophagy?	Unlikely
Insulin impact	Negligible

Why plain matcha keeps you fasted

Matcha is whole green tea leaf ground into a fine powder, so you drink the leaf itself instead of an infusion. That adds a few calories compared with steeped green tea, about 3 to 4 per gram, which is still far too little to end the fasted state. It also brings caffeine and L-theanine, and many people find a bowl in the late morning makes the last hours of a fast easier.

Caffeine and the latte problem

Matcha has more caffeine than many people expect. Studies report roughly 19 to 44 mg per gram, so a teaspoon can hold 40 to 90 mg, up to about as much as a cup of coffee, and on an empty stomach that can mean jitters or nausea. Café matcha lattes are made with milk and often a pre-sweetened powder, and a medium cup commonly passes 200 calories with plenty of sugar.

How much is safe

One or two servings of plain matcha during the fast are fine. Count them toward a daily caffeine total under 400 mg and have the last one by early afternoon so it does not cut into your sleep.

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Frequently asked questions

Does a matcha latte break a fast?: Yes. Milk adds calories, protein and lactose, and many café versions use sweetened powder. Keep lattes for your eating window.
How much caffeine is in matcha?: Roughly 19 to 44 mg per gram depending on the tea, so a 1 g serving has about 20 to 45 mg and a teaspoon about 40 to 90 mg.
Does matcha break autophagy?: Plain matcha is unlikely to. It has only a few calories, and lab studies link its main catechin, EGCG, to autophagy, though there is no human evidence that matcha boosts it during a fast.
Can I sweeten matcha while fasting?: A few drops of stevia or monk fruit keep it fast-friendly. Sugar, honey and syrups end the fast.