Apple Cider Vinegar

Apple cider vinegar is permitted without conditions, and it has more claims around it than evidence. These are the questions our naturopaths ask in store, mostly about dose, format and your teeth.

A good fit if

• You'll take it diluted, with food, at 15 to 30 mL a day
• You want the after-meal effect, which is the best-supported thing it does
• You're willing to check the acetic acid content on a capsule label, or go with the liquid instead
• You'd rather be told which claims we can't stand behind

Check with us first if

• You take diabetes medicine or insulin. There's no interaction data, and the way it works is clear enough that it's worth a conversation.
• You take a diuretic that lowers potassium, digoxin or laxatives. It's the same reasoning, and a case report shows real potassium loss at high intakes.
• You have reflux or an existing stomach problem, since vinegar is an acid and there's no evidence it reduces stomach acid.
• You already have worn enamel or sensitive teeth.
• You're pregnant, breastfeeding or buying for a child. There's no evidence at all for these groups.
• You're taking it for a diagnosed condition rather than alongside meals.

• Liquid, raw and unfiltered (with the mother). Best known for: Everything the human trials actually tested. Absorption: 15 to 30 mL a day, diluted, giving 750 to 1,500 mg of acetic acid. Typical use: No human study compares raw vinegar with the mother against filtered, so any benefit from the mother is unproven.
• Liquid, filtered or pasteurised. Best known for: Clear, with a longer shelf life. Absorption: The same acetic acid content and the same trial doses. Typical use: Human trials rarely say which they used, so the evidence arguably covers both.
• Capsules and tablets. Best known for: No taste, and no contact with your teeth. Absorption: This is the gap that matters. Pills used as placebo comparisons held 1 to 2% of a 15 mL liquid serve. Typical use: Look for a stated acetic acid content, and know that most products don't state one. The upside is real: the pill group showed no tooth wear.
• Gummies. Best known for: Pleasant to take and popular. Absorption: Our sources hold no human trial of any apple cider vinegar gummy. Typical use: The acid content is generally low, and the sugar works against the reason you are taking it.
• Powders and drink sachets. Best known for: Convenience. Absorption: No human trial. Typical use: Usually dried onto a maltodextrin carrier.
• Topical soaks and rinses. Best known for: Diluted to about 0.5% acetic acid. Absorption: Two controlled human tests found no benefit for the skin barrier or skin bacteria. Typical use: Almost three-quarters of people reported irritation. We won't recommend it.
• Generic vinegar in a medicine. Best known for: A regulatory difference worth knowing. Absorption: Does not apply. Typical use: Schedule 1 allows generic vinegar only as a flavour, capped at 5%. Apple cider vinegar has its own entry with no conditions and can be the active ingredient.

Reference values. There's no recommended intake for apple cider vinegar. It's a food and a ferment, not a nutrient.

Typical supplemental range. 15 to 30 mL a day of liquid, diluted in water and taken with meals. 15 mL gives you about 750 mg of acetic acid and 30 mL about 1,500 mg. One analysis found you need more than 10 mL a day to see an effect on blood sugar.

Upper level. Australia's permitted ingredients list (Schedule 1) sets no cap. The practical limit is the trial range of 15 to 30 mL a day. Harm shows up well above that: tooth enamel wear at 3.6 g of acetic acid a day over eight weeks, and one case report of low potassium and osteoporosis after roughly 250 mL a day for six years, which is about ten times the highest trial dose.

Worth knowing. Dilute it, drink it with a meal rather than sipping it through the day, and don't brush your teeth straight after. If you're buying capsules, look for the acetic acid content, not the total milligrams. What you need depends on your age, diet and health, so talk to one of our naturopaths.

Food first, where the diet allows it.

• Apple cider vinegar as a food: the same bottle on a supermarket shelf is a food under the Food Standards Code, not a listed medicine
• Other vinegars: the postprandial glucose finding covers vinegar generally, not apple cider vinegar specifically
• Other fruit vinegars: don't generalise across them: a fermented Prunus mume vinegar trial for fatigue was null

If any of these sound like you, talk to one of our naturopaths or your doctor before you start.

• Your teeth. A randomised trial with blinded dental checks found 3.6 g of acetic acid a day for eight weeks raised tooth erosion scores by 18%, and enamel does not grow back. Dilute it, drink it with a meal rather than sipping it, and don't brush straight afterwards.
• Very high intake over a long time. A case report describes a woman taking about 250 mL a day for six years who developed low potassium (hypokalaemia), potassium loss in her urine and osteoporosis, with a bone density T-score of -3.0. That is roughly ten times the highest trial dose.
• Tablets that get stuck in the food pipe (oesophagus). A side-effect report describes injury to the oesophagus from an apple cider vinegar tablet. Take tablets sitting or standing upright, with plenty of water.
• Skin. Daily diluted soaks caused mild side effects in almost three-quarters of people in a controlled trial, with no benefit for the skin barrier or skin bacteria. Using it undiluted on skin can damage it.
• Reflux and stomach complaints. Vinegar is an acid, and there is no evidence it reduces stomach acid. Any use of vinegar for indigestion points the other way, and rests on traditional grounds only.
• You take diabetes medicines, insulin, diuretics that lower potassium, digoxin or laxatives. Our sources have no interaction data. How something might work is not evidence, so we won't write it up as if it were. Ask your prescriber.
• Pregnancy, breastfeeding and children. We found no data in any of these groups.
• Product quality. A lab analysis of eight tablet brands found wide variation in pH and acid content, and could not confirm apple cider vinegar was present at all.