Hi is apple cider vinegar harmful for bones? i took for three day that apple cider vinegar and my knees hurting soo much

Why would you take?: Apple cider vinegar when consumed in large amounts may lower potassium levels, promote osteoporosis, raise renin levels, alter insulin levels, & even burn your esophagus. Apple cider vinegar tablets are not well regulated, may vary dramatically in terms of vinegar content from brand to brand, & lack evidence of efficacy.

Proven vs unproven: By definition, "alternative" is different than modern western medicine. Generally any drug, herb, treatment, or procedure that stands up to rigorous scientific scrutiny is included in modern medicine. The problem is that many alternative practices, herbs etc do not stand up to scientific scrutiny and cannot be shown to work. They therefore remain "alternative". Be careful and watch your wallet.