Apple cider vinegar advocate Paul Bragg was way ahead of his time.
[Paul Bragg- Wikipedia] inegar (acetic acid) was recently shown to reduce disease activity in cases of experimental colitis in laboratory animals. Apple cider vinegar increased levels of acid-forming bacteria such as Acidophilus and Bifidus. [Journal Agriculture Food Chemistry 2016]
An apple a day keeps the doctor away may now be more than folklore.
There is a growing body of evidence that gut bacteria control low-grade inflammation that is the hallmark of aging (called inflammaging). A report published a few years back showed that apple components, particularly apple pectin, increase the number of good bacteria in the human gut (intestines). [Anaerobe 2010]