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Drinking apple cider vinegar (ACV)—often one tablespoon mixed in 8 ounces of water—has been a popular natural remedy for many years. Then along came capsules, which brought the benefits of ACV to people who weren’t thrilled with even its diluted taste. But this trendy supplement didn’t really become a phenomenon until the recent advent of ACV gummies. One popular brand has nearly a quarter-million online reviews, with three-quarters of reviewers awarding it five stars.
What Is Apple Cider Vinegar?
ACV is made with a two-step process. First, apples are crushed and fermented with a yeast, which produces alcohol—apple cider. Second, that mixture is fermented further with an acetic acid bacterium (Acetobacter)—a specific type of probiotic that produces acetic acid, which is believed to the active ingredient responsible for vinegar’s benefits.
All vinegars are made this way, but fermentation of other, commercial vinegars may be speeded up with oxygen, agitation, or other processing methods. ACV is usually naturally fermented.
Unfiltered apple cider vinegar contains a cloudy substance: the “mother,” which develops during fermentation and contains a combination of yeast, probiotic bacteria, and enzymes. The mother is believed to provide additional benefits from the probiotics.
Science-Backed Benefits of ACV
In addition to its long history of use, modern clinical trials have identified specific benefits of apple cider vinegar.
Blood Sugar Control
Both ACV and other types of vinegar have been found to reduce the rise in blood sugar after meals, especially meals with starchy foods. Two mechanisms help to produce this effect.
Vinegar inhibits the alpha-amylase enzyme, which breaks down starches and sugars—foods that cause unhealthy spikes in blood sugar. As a result, absorption of starch is reduced. Vinegar also improves insulin sensitivity, meaning that blood sugar is utilized more efficiently by tissues to produce energy instead of accumulating in the blood.
Both these actions help to prevent diabetes. And among type 2 diabetics, they help to keep blood sugar at healthier levels.
One study, at Arizona State University in Mesa, tested apple cider vinegar on people at risk for diabetes as well as those who already had the disease. It concluded that the vinegar may have effects similar to metformin, the first-line drug for type 2 diabetes.
The largest trial of apple cider vinegar for weight loss was done on 155 Japanese men and women between the ages of 25 and 60. By American standards, they were overweight but not obese.
Study participants were divided into three groups: one drinking 8 ounces of liquid with one-half tablespoon of apple cider vinegar twice daily, another consuming a drink with 1 tablespoon of the vinegar twice daily, and a third group drinking a placebo that was flavored to taste like vinegar. The people in the study did not change their diets.
After 12 weeks, those drinking the lower dose of vinegar lost an average of 2.6 pounds and those drinking the higher dose lost an average of 4.2 pounds.
Another study found that drinking 1 tablespoon of apple cider vinegar with lunch and dinner, while following a reduced-calorie diet for 12 weeks, resulted in an average weight loss of 8.8 pounds. People on the same diet who did not drink vinegar lost less (an average of 5 pounds). And compared to the no-vinegar dieters, those taking apple cider vinegar also saw their levels of cholesterol and triglycerides improve significantly.
Although there haven’t been any human trials testing apple cider vinegar for digestion, lab studies have shown that it is antimicrobial. It kills (in the lab) candida, E. coli, and other harmful bacteria that can cause digestive and other health problems.
How to Take ACV for Maximum Effectiveness
Studies have used ½–2 tablespoons of apple cider vinegar mixed in water and taken with one or two meals per day. Some people drink it through a straw to prevent the acid from damaging tooth enamel. Apple cider vinegar can also be used in salad dressings, sauces, marinades, soups, and hot drinks.
Gummies are popular because they are formulated to have a pleasant taste and are convenient. Suggested servings are usually 1–2 gummies, once or more per day. Capsules are another popular alternative to the sour taste of vinegar. A common serving is two capsules.
Capsules and gummies avoid the potential risk of acid in the vinegar damaging tooth enamel, and some contain additional nutrients for specific benefits, such as immune health. However, compared to liquid apple cider vinegar, capsules and gummies may contain less acetic acid, the active ingredient in vinegar. Whichever form you choose, make sure it is made using organic apples, as conventionally farmed apples rank high on the pesticide meter.
A Short and Fascinating History of Vinegar
Vinegars can be made from many carbohydrate-rich foods, including various fruits and grains. They all contain acetic acid, but the taste and perhaps other properties vary, depending upon the food source.
Legend has it that vinegar was discovered several thousand years ago after some unattended grape juice fermented and its ability to preserve food was recognized. In ancient Greece, around 420 BC, Hippocrates treated wounds with vinegar. And a few hundred years later, Cleopatra dissolved precious pearls in vinegar to make a love potion.
By the 18th century, vinegar was used to treat many ailments, including fluid retention, poison ivy, croup, stomachache, and elevated blood sugar. And diabetics were encouraged to drink teas made from vinegar.
Make it! — Recipes with Apple Cider Vinegar