Drinks · ~3 kcal per tablespoon (15 ml) in water
Does apple cider vinegar break a fast?
A tablespoon of apple cider vinegar has about 3 kcal. Diluted in water, it is safe for weight loss and blood sugar and grey for the other goals.
The answer for each goal
Weight loss
SafeAutophagy
Grey areaGut rest
Grey areaBlood sugar
SafeCider vinegar has about 21 kcal per 100 g, so the amounts stirred into water stay small. A teaspoon adds about 1 kcal, a tablespoon about 3 and two tablespoons about 6. All of these sit far below the 50-calorie rule of thumb, which no health body has set.
This site judges each item against four goals it made up itself. Diluted vinegar is safe for weight loss and for blood sugar. In meal trials, people who took vinegar with food had a smaller rise in blood sugar afterwards. Gut rest is grey, because in a small trial vinegar slowed how fast the stomach emptied. Autophagy is grey too, since vinegar has a few calories and no study has tested it.
The blood-sugar effect needs a meal to act on. If steadier blood sugar is the aim, take vinegar with your first meal. Trials used 15 to 30 ml a day mixed into a drink. A 2026 review covering 38 trials found that vinegar takers lost about 1 kg more than people who did not take it.
Watch out
Always dilute it, because vinegar is an acid that can wear tooth enamel. If you take insulin or another medicine that lowers blood sugar, ask your doctor before adding daily vinegar.
Questions people ask
When should I drink apple cider vinegar while intermittent fasting?
With your first meal, if blood sugar is your reason. The trials that found a smaller blood-sugar rise gave vinegar with food. Mid-fast, a diluted tablespoon keeps a weight-loss fast going, with no meal for it to act on.
Do apple cider vinegar gummies break a fast?
They can, because brands differ. Check the label for sugar per gummy. Any sugar ends a blood-sugar fast and adds calories to a weight-loss fast.
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