You may have noticed your supermarket offering more types of vinegar lately. Sure, balsamic and apple cider vinegars are veterans of the condiments aisle, but new shelf neighbors, like coconut, champagne, pomegranate, and raspberry are moving in.
That’s probably at least in part due to recent research showing that small amounts of vinegar, consumed daily, could support your health in important ways. But which vinegars are evidence-backed to promote health, in addition to lending some zing to your cooking?
Here’s what research says about vinegar’s effects on blood sugar, obesity, and fighting colds—and which kind to reach for.
A long-standing tonic
Since the Babylonians first made vinegar about 7,000 years ago, cultures around the world have used it for medicinal purposes. Hippocrates mixed apple cider vinegar with honey to treat ancient Greeks’ respiratory troubles. Europeans in the Middle Ages believed it protected against the plague, while the Chinese used rice vinegar to treat pain.
Several scientific studies later, dietitians such as New Jersey-based Erin Palinski-Wade are increasingly recommending vinegar to their clients. “What I love about using vinegar is that it may offer a variety of benefits with little to no downside,” she says.
What makes vinegar special
One defining ingredient could explain vinegar’s health benefits: acetic acid. After it’s swallowed, acetic acid turns into acetate, a fatty acid that’s good for digestion, metabolism, and energy production.
Every type of vinegar starts out as some form of sugar, aka carbohydrate—like apples, used to make apple cider vinegar, or grapes, which make red wine vinegar. The carb is pressed into liquid-form and fermented by yeast into alcohol, which is then fermented into acetic acid. This process endows vinegar with significantly more acetic acid than any other food, says Carol Johnston, a professor of nutrition at Arizona State who studies vinegar.
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The FDA requires all vinegars sold in the U.S. to contain at least 4% acetic acid, although different bottles have a range. Some vinegars, especially balsamic, tend to also be high in polyphenols: compounds in plants that protect us from cellular damage, inflammation, and infection.
Apple cider vinegar
The most researched type is apple cider vinegar, or ACV. Studies show that a bit of ACV before or during meals can drive down blood sugar, or glucose, measured right after eating and, with consistent use, it may contribute to improved blood sugar control over several months. These effects are pronounced with high-carb foods, which could otherwise spike blood sugar. “It’s clear that drinking vinegar with a starchy meal will reduce the amount of glucose in the bloodstream,” Johnston says.
She and others have found that the acetic acid in ACV affects certain hormones that slow the rate at which the stomach sends food to the intestines. Because the glucose enters the bloodstream more gradually, regular intake of ACV could, over time, reduce the risk of developing Type 2 diabetes.
Small studies also point to healthier weight, perhaps due to vinegar’s slowing effect on the stomach. And recent research found lower blood fat levels in overweight adults who consumed ACV, suggesting better heart health, in addition to lower glucose.
Most of these benefits have been researched at 2-4 tablespoons per day. But larger studies are needed, says Sapha Shibeeb, a senior lecturer in laboratory medicine at RMIT University in Australia who published a research review on ACV. “There is an effect, but we have to be careful in saying what kind of effect and the magnitude.”
The mother of all benefits
Some brands of ACV are unfiltered and unpasteurized, with a distinctly visible result: a cloudy substance floating in its liquid. This hazy residue, called “the mother,” contains bits of proteins and healthful enzymes and bacteria from fermentation. Companies claim the mother contributes to ACV’s benefits—and charge more for these raw ACVs.
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Some scientists think it’s worth it. In her lab, Darsha Yagnik, an immunologist at Middlesex University, has found that ACV with the mother is uniquely potent in helping immune cells kill off pathogenic microbes in the lab. “When I looked at other vinegars, they weren’t as effective,” she says, such as stronger acids you wouldn’t eat, like sulphuric. “The mother includes microbiome-friendly bacteria which support digestive immunity and nutrient absorption,” Yagnik says.
Based on this research, Yagnik thinks that ACV, in addition to improving blood sugar, can help stave off illness—just as the ancients believed. Yagnik always packs small bottles of ACV, diluted with water, when traveling on the tube in London. “If someone nearby has a cold, I’ll have a little,” she says. “I think it absolutely helps.”
“Because the mother contains bacteria, it could be beneficial as part of a healthy microbiome in the gut,” Shibeeb adds. He notes that even the more expensive vinegars with the mother are still fairly cheap.
Others aren’t buying it. Robert Hutkins, a microbiologist at the University of Nebraska, says that, although the mother’s microbes may do wonders in the lab, they can’t compete or thrive in our microbiomes because they need air to survive. “They won’t make much of a living in the gut” for killing pathogens, he explains.
Johnston says the mother has only “trace amounts” of healthy substances, yielding nothing beyond the benefits of acetic acid. “It doesn’t pay to get the ones with the mother,” she says. “Right now, the science is with the acetic acid,” which is in all vinegars regardless of type, for benefits like reducing blood sugar.
Vinegar’s fermentation may have advantages
Vinegar’s fermentation process differs from fermented vegetables like cucumbers and cabbage, which may translate into some unique benefits.
Vegetables are fermented using healthy microbes. When eaten, the microbes go through the gut microbiome, where they slowly produce several fatty acids that fight infections and inflammation.
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One of these fatty acids is acetate. But when making vinegar, fruit fermentation may work more directly. The fruit fermentation yields acetic acid, which gets turned into acetate well before reaching your gut—so it’s more rapidly absorbed, potentially making it a valuable source of energy for the cells. “Basically, what you’re doing is bypassing the need for the microbiome to do the work,” Johnston says.
Fermented foods like vegetables with live microbes provide equally important—or perhaps greater—benefits. “I’m a big advocate of including these fermented foods in one’s diet,” Hutkins says. Aim for a mix, including types of vinegar. “ACV isn’t a superfood because there’s no such thing. Each of these foods is just part of an overall healthy diet.”
Red wine and balsamic vinegars
The benefits of ACV probably apply to some other vinegars. ACV is commonly sold in the U.S. simply because apples are popular here, not because they’re especially healthy or flavorful. “It’s marketing,” Johnston says. “In the Mediterranean, they have lots of grapes, so they have more balsamic vinegar and red wine vinegar.”
Johnston has found that a few tablespoons of red wine vinegar, consumed daily, improve glucose control and, in just four weeks, people’s rates of depression go down. Again, vinegar’s acetic acid could be the benefactor; acetate plays a role in improving brain inflammation, plasticity, and overall cognition.
Polyphenols may contribute as well. Red wine vinegar has more polyphenols than other fruit vinegars, with antioxidant effects that may counter depression, wrote the study’s authors.
Another vinegar high in polyphenols is balsamic, especially versions made in parts of Italy. “The polyphenols are concentrated,” Johnston says, resulting in a thicker, darker vinegar. Look for bottles, albeit pricier ones, with designations of production in the Modena and Reggio Emilia regions. Balsamic vinegar, combined with food, may slow down stomach enzymes for better digestion.
The rest of the pack
Some findings suggest rice vinegar offers similar benefits. Fewer studies have looked at other vinegars, such as coconut, pomegranate, or sugarcane. Limited research suggests that sugarcane vinegar, for instance, lowers blood fats.
These less-studied vinegars have lower acetic acid and polyphenols than apple cider, red wine, and balsamic. But they still offer more acetic acid than non-vinegar foods; Palinksi-Wade recommends letting your flavor preferences guide you. They also may contain at least some of the nutrients from their original food sources, compared to standard white vinegars, which are produced through a simpler fermentation process that strips away most of the potentially beneficial compounds, Hutkins adds.
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Last year, Hutkins and colleagues at Georgetown University Medical Center found that drinking kombucha—containing vinegar, live microbes, and other beneficial ingredients like ginger—affects blood glucose positively.
How to drink vinegar
While vinegar may be good for you, “it’s not a drug,” Johnston notes. As part of an overall healthy diet, “it’s going to have a more gradual effect on measures like blood sugar” than pharmaceuticals.
Precautions should be taken with vinegar due to its acetic acid; in concentrated forms, it can damage the teeth, mouth, and throat. Avoid straight-up vinegar shots. Mix it with water, juice, or food. “Let’s not overdo this,” Johnston says. “You’re dealing with an acid.”
People who have chronic kidney disease should be particularly careful with their vinegar consumption, since their kidneys are challenged to process the excess acid from vinegar.
Dilute one tablespoon into 8 ounces of fluid, Palinski-Wade says, and consider drinking through a straw. “Maybe gargle with water afterward, just to make sure your tooth enamel is protected,” Yagnik suggests.
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Avoid having more than four tablespoons per day. “The highest you’d go is two tablespoons with one meal, and two tablespoons with a second meal that day,” Johnston says. If you’re new to vinegar, start slowly with one daily tablespoon. “Build up gradually to avoid any digestive issues,” Palinski-Wade says.
For blood sugar benefits, have vinegar before your heaviest meals, Shibeeb says. Yagnik takes it 5-10 minutes after eating in hopes of helping her immunity.
If you’re cooking vinegar to make a sauce, like a balsamic reduction, you’re probably losing some of the acetic acid, along with some benefits, Hutkins says.
Pending further research, we don’t yet know the long-term benefits of regular vinegar intake, nor its side effects. Studies as long as 12 weeks don’t reveal any notable downsides, at least. Based on what we know today, “experimenting with vinegar in the diet is a great option for most individuals,” Palinski-Wade says, “with little risk.”