ALL vinegar is acidic.

The pH of apple cider vinegar is typically between pH 4.25 and 5.00.

On my scale that isn't alkaline. It erodes tooth enamel just like any other acid.

Drinking it every day like your model friend is awful for you. Damages mucous membranes in the mouth and throat. Erodes tooth enamel. Lowers the body's potassium. And thins the blood (which could be good for some folks but no better or safer than a baby aspirin).
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