Apple cider vinegar creates the seemingly paradoxical effect of making the digestive system more alkaline, as the stomach sees the inrush of acid and reacts by stopping acid production.
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I use a European product called Crastan Effervescente (con succu limone), which tastes good as the name implies and gives you the sodium bicarbonate. There exist similar American products.
I had some GI problems in my 20s, and out of desperation, found baking soda to be the best solution.
The past couple of years, I’ve been taking a swig (~tbls) of apple cider vinegar before bed, or after an acidic dinner, and have rarely had the need for baking soda since.
That is, not waking up with acid reflux in the middle of the night.
Brioschi is another lemon-flavored bicarbonate of soda that's good and effective at settling an acid stomach. It used to be more widely advertised and was even available in local pharmacies. At least you can still buy it on Amazon.