Apple vinegar, more commonly called apple cider vinegar (ACV), is a fermented liquid made from crushed apples. It contains about 5% to 6% acetic acid, the compound responsible for its sharp taste and most of its purported health effects. It’s one of the most popular pantry staples that doubles as a home remedy, used for everything from salad dressings to blood sugar management.
How Apple Vinegar Is Made
Production follows a two-stage fermentation. In the first stage, yeasts feed on the natural sugars in crushed apple juice and convert them into alcohol (ethanol), essentially making a rough apple cider. In the second stage, called acetification, a different group of microorganisms, acetic acid bacteria, oxidize that alcohol into acetic acid. This is what gives vinegar its sour smell and tangy bite.
The process can take anywhere from weeks to months depending on the method. Faster commercial techniques force air through the liquid to speed up bacterial activity, while traditional methods let it ferment slowly in barrels. The slower approach tends to produce the cloudy sediment at the bottom of the bottle known as “the mother,” a colony of natural bacteria and yeasts. Filtered, pasteurized versions are clear and shelf-stable but lack that bacterial culture. Both types contain the same concentration of acetic acid.
Blood Sugar Effects
The most studied health claim around apple vinegar involves blood sugar. Acetic acid appears to inhibit certain digestive enzymes, including alpha-amylase, which breaks down starches into sugar. By slowing that breakdown, less glucose enters the bloodstream at once after a meal, flattening the typical post-meal blood sugar spike.
A systematic review and meta-analysis published in Frontiers in Nutrition examined controlled clinical trials in people with type 2 diabetes and found that ACV improved fasting blood sugar, long-term blood sugar markers, and insulin sensitivity. These effects are modest, not dramatic, but they’re consistent enough across studies to be taken seriously. The practical takeaway: a small amount of vinegar before or during a starchy meal may blunt the glucose response, which is most relevant for people managing insulin resistance or diabetes.
Weight and Appetite
Apple vinegar slows gastric emptying, meaning food stays in your stomach longer after a meal. This can promote a feeling of fullness and reduce the urge to eat again soon after. Animal research suggests that acetate (the active form of acetic acid once absorbed) may also influence appetite-regulating hormones in the gut, including GLP-1 and PYY, both of which signal satiety to the brain.
A randomized, double-blind, placebo-controlled trial published in BMJ Nutrition tested ACV in young adults with overweight and obesity and found measurable reductions in body weight. That said, the effect sizes are small. Apple vinegar is not a weight loss tool on its own. It may offer a slight edge alongside dietary changes, but expecting dramatic results from a tablespoon of vinegar is unrealistic.
Cholesterol and Lipid Changes
In one randomized controlled trial of 73 people with type 2 diabetes, those who consumed about two tablespoons (30 ml) of apple cider vinegar daily for eight weeks saw their total cholesterol drop by an average of 24 mg/dl and their LDL (“bad”) cholesterol drop by about 25 mg/dl. The control group’s numbers barely moved. Triglycerides, however, showed no meaningful change in either group.
These results are promising but come from a single trial in a specific population. Whether the same lipid improvements would appear in people without diabetes, or hold up over longer periods, remains unclear. The cholesterol reductions are roughly comparable to what you’d see from moderate dietary changes like increasing soluble fiber intake.
Risks and Side Effects
Apple vinegar is acidic, with a pH typically between 2.7 and 3.95. That acidity creates real risks when consumed undiluted or in large amounts.
Tooth enamel is the primary concern. In lab studies, teeth immersed in vinegar lost 1% to 20% of their mineral content after just four hours. Over time, regularly sipping undiluted vinegar can degrade enamel, leading to increased sensitivity, pain, and a higher risk of cavities. Drinking through a straw and rinsing your mouth with plain water afterward can reduce contact with teeth, but the risk doesn’t disappear entirely.
The esophagus is also vulnerable. Apple cider vinegar can cause throat irritation and, in rare cases, esophageal ulceration and burning. Acetic acid is actually the most common acid involved in throat burns from liquids accidentally swallowed by children. One documented case involved a woman who developed throat burns after an ACV tablet became lodged in her esophagus. People with acid reflux or a history of esophageal problems should be especially cautious.
There are also reports of apple vinegar contributing to low potassium levels, which can cause muscle weakness and cramping. This is particularly relevant if you take medications that also lower potassium, such as certain diuretics.
How to Use It Safely
The most common recommendation from nutrition experts is to mix no more than one tablespoon of apple cider vinegar into an 8-ounce glass of water, tea, or another beverage, and to limit yourself to one serving per day. Drinking it straight is a bad idea. The dilution protects your throat, stomach lining, and teeth from concentrated acid exposure.
Timing it before or during a meal maximizes the blood sugar benefits, since the goal is to slow starch digestion as it’s happening. Some people prefer to add it to salad dressings or marinades instead of drinking it, which delivers the same acetic acid in a more palatable way. Apple cider vinegar gummies and capsules are also widely available, though their acetic acid content varies and is often lower than what’s used in clinical studies.
If you notice throat irritation, stomach discomfort, or worsening heartburn, those are signs to reduce the amount or stop. The benefits of apple vinegar are incremental, not transformative, so the tradeoff isn’t worth it if it’s causing you problems.