This is a good question. Many people believe apple cider vinegar works. But studies which can prove that are very limited.
As I just mentioned, there's very limited supporting evidence proving that it works. There is one study, though. It showed that unfiltered apple cider vinegar helps prevent heartburn.
Consuming something that contains a lot of acid to relieve an acid-related disease just doesn't sound right. But some people claim that it works by buffering the acidity level in the stomach as acetic acid (main component of apple cider vinegar) is a weaker acid than hydrochloric acid (the stomach acid).
You should consult your doctor before you try the natural remedy.
Keyword: apple cider vinegar acid reflux