What Is Apple Cider Vinegar? Cider vinegar comes from the fermented juices of crushed apples. It contains large quantities of acetic acid & citric acid. It also contains vitamins B1, B2 & B6, biotin, folic acid, niacin, pantothenic acid & vitamin C. It is also high in pectin, a form of dietary fiber. What Does Apple Cider Vinegar Do? The pectin in apple cider vinegar may help to maintain healthy blood sugar levels. Studies suggest apple cider vinegar may also help to maintain a healthy cardiovascular system.