Taking apple cider vinegar in amounts normally found in food is LIKELY SAFE. In the case of eating or using for the purpose of treating disease. It should only be used for a short time. Other precautions are as follows.

Taking large amounts vinegar or more than 237 milliliters per day is POSSIBLY UNSAFE. This can lead to low blood potassium levels or other side effects, such as enamel damage. or a burning sensation in the mouth and throat. It was reported that people who consumed 250 ml of apple cider vinegar per day for 6 consecutive years had symptoms of osteoporosis and hypokalemia. The other had laryngeal pain and trouble swallowing for up to six months after the tablet was stuck in the throat for 30 minutes, which was thought to be the result of an apple cider vinegar pill. UFABET

Applying to the skin or any part of the body should be diluted to a lower concentration of the acid first to prevent sunburn

Pregnant or breastfeeding women should not consume large amounts or high concentrations vinegar. because there is no safety report.  

Apple cider might result in lower blood sugar levels or digestive problems. People with diabetes should consult a doctor before taking it. Because it may need to adjust the diabetes medication intake. and regularly check blood sugar levels

May interact with certain medications such as digoxin, diabetes medications, heart medications, diuretics, laxatives, etc. People who take medications regularly or have underlying conditions. Consult your doctor before use.

People with problems with their strength or bone density should use with caution.