Apple cider vinegar has long been a pantry staple, thanks to its versatility as an ingredient in everything from salad dressings to sauces and stews. More recently, this vinegar made from fermented apple juice has also gained a reputation for its medicinal properties.
The tart-tasting liquid has been promoted for accelerating weight loss, lowering blood sugar and cholesterol levels, and boosting energy. Which of the claims are backed up by science? Fortune asked two nutritional experts to dig into the evidence surrounding apple cider vinegar’s potential benefits.
The health benefits of apple cider vinegar
Apple cider vinegar does have certain healthful properties, which are largely due to its acetic acid content. “Acetic acid is a really important metabolite in our bodies, and the only dietary source of acetic acid is vinegar,” Carol Johnston, Ph.D., professor of nutrition and associate dean in the College of Health Solutions at Arizona State University, tells Fortune.
But as a cure-all, apple cider vinegar doesn’t hold up to scientific scrutiny. “We don’t have evidence to back up a lot of the claims,” says Johnston. She should know, since she’s been studying vinegar—and not just the apple cider variety—for decades.
Apple cider vinegar and blood sugar
The most “robust” evidence is for apple cider vinegar’s effects on blood sugar, Johnston says. In a 2021 review of nine studies published in BMC Complementary Medicine and Therapies, apple cider vinegar lowered fasting blood sugar and HbA1c (an average of blood sugar levels over three months) in people with type 2 diabetes. It also brought down their total cholesterol.
How might apple cider vinegar lower blood sugar? Three mechanisms are likely involved, says Johnston. One is by slowing stomach emptying after a meal, which delays the movement of glucose (sugar) into the bloodstream. The second is by blocking the breakdown of starch into glucose. And the third is by increasing the amount of glucose muscle cells take in. “The result is you have less glucose in your blood,” Johnston says.
Apple cider vinegar and weight loss
Some studies have suggested that apple cider vinegar can boost weight loss by increasing feelings of fullness after a meal. But any weight loss it might bring about is minimal—a pound or two per month.
“If you are already implementing diet and lifestyle changes, apple cider vinegar may be able to give you a slight advantage by helping you control your hunger while you eat less food. The scientific evidence falls short of indicating that apple cider vinegar is a magic bullet to produce weight loss on its own,” Kristine Dilley, a registered dietitian at The Ohio State University Wexner Medical Center, tells Fortune.
Apple cider vinegar’s potential benefits
Other potential applications are intriguing, but the research is still preliminary. For instance, vinegar might have a future role in treating depression because of its effects on brain metabolism. It’s also a good source of polyphenols, plant-based antioxidants with anti-inflammatory properties.
Johnston sees the potential. “I think there’s going to be a lot more that we’re going to learn from vinegar in the future,” she says.
She also notes that vinegar doesn’t need to be of the apple cider variety. Any vinegar with a concentration of at least 5% acetic acid should offer the same benefits—including red wine and balsamic vinegar.
How much apple cider vinegar should you take?
Our experts recommend taking 1 to 2 tablespoons of apple cider vinegar daily—and no more than 4 tablespoons in total. “The easiest and safest way to consume apple cider vinegar is to work it into your daily diet by adding it to foods you already consume,” Dilley suggests. Apple cider vinegar makes a good addition to salad dressings, marinades for chicken or fish, pickled vegetables, soups, and stews.
If you want to take it on its own, Dilley recommends diluting it with 8 to 12 ounces of water. Apple cider vinegar is highly acidic. Drinking it straight as a “shot” could irritate the lining of your mouth or damage your tooth enamel.
Dilley doesn’t recommend using apple cider vinegar capsules or gummies, which aren’t regulated by the FDA. These supplements may not contain the amount of vinegar listed on the label.
Check with your doctor before you take apple cider vinegar, because it can interact with certain medications—especially drugs that lower blood sugar or potassium, Dilley says. Cooking with it shouldn’t pose a problem with your medications.
Who shouldn’t use apple cider vinegar?
Avoid apple cider vinegar if you have gastroesophageal reflux disease (GERD) because it can irritate sores in the lining of your esophagus, advises Johnston.
Vinegar also isn’t recommended for people with slow stomach emptying called gastroparesis. Because vinegar also slows stomach emptying, it could make the condition worse.
The bottom line on apple cider vinegar
For now, the best-researched health benefit of apple cider vinegar is for lowering blood sugar. Still, Johnston considers vinegar a worthwhile addition to the medicine chest. After all, it’s been part of medicine since Hippocrates used it for treating wounds. “Anything that has been in the medicinal world for 2,000 years has to have some legitimacy,” she says.
