Apple cider vinegar (as a liquid) may reduce or slow the increase in blood sugar after eating (although it may not help people with diabetes) and may modestly aid with weight loss. The effects of apple cider vinegar may be due to its acetic acid content, which tends to be about 5% in vinegars (equaling about 800 to 900 mg of acetic acid per tablespoon). There is no good clinical research supporting the use of pills containing apple cider vinegar in powder form — these generally provide a much smaller amount of acetic acid per serving but can be dangerous if the acetic acid is too highly concentrated.
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