Updated on March 8, 2023.
If you spend any time on the internet or social media, you’ve likely run across a health influencer touting the benefits of apple cider vinegar (ACV). Many fans of ACV encourage starting the day by drinking a mixture of water and ACV, claiming health benefits that include stabilized blood sugar, weight loss, and better digestion, among others. Sounds too good to be true, right? Well, it may be.
What’s ACV and where does it come from?
Apple cider vinegar is apple juice that has been fermented. In a nutshell, yeast is added to apple juice to convert it into alcohol. Then, certain bacteria are added to turn that alcohol into acetic acid, or ACV.
You may have heard the term “mother,” which is a mix of the yeast and bacteria which result in the darker particles you see floating about in some ACV bottles. These varieties are considered unfiltered because the “mother” hasn’t been removed.
Six ACV health claims—debunked
Before you replace your morning cup of coffee with a daily dose of ACV, here’s what science says about the rumored benefits for certain health conditions. Most have little evidence to support them.
Cancer: It’s been suggested that regularly ingesting ACV can turn the body's overall pH (the measure of acidity or alkalinity) more alkaline, and that this may kill cancer cells. But the research doesn't back this up. In fact, a 2016 systematic review published in the journal BMJ Open concluded that there’s not enough evidence to support or reject the alkaline-cancer prevention theory.
That said, the body regulates its pH levels on its own, so the foods you eat probably have little effect.
Blood pressure: In the early 2000s, a few studies conducted on lab rats suggested that a diet incorporating vinegar lowered systolic blood pressure. Since then, no significant human studies have come to the same conclusions. In fact, a small randomized trial published in Clinical Nutrition ESPEN found that daily apple cider vinegar had no effect on blood pressure of adults with type 2 diabetes and high cholesterol.
Acid reflux: Some say that the acid in ACV can help digestion because the bacteria in the “mother” contains probiotics. But Miriam Zylberglait, MD, an internist and geriatric medicine specialist in Miami, Florida, says ACV can make acid reflux worse.
"When you consume ACV, you may actually create more reflux and have more stomach issues because of the possible effects on gastric motility, the delay on stomach emptying, and the acidic nature of the beverage," Dr. Zylberglait explains. “In some cases, reflux and other gastric problems are associated with altered motility of the digestive system, meaning that the stomach is working slowly. You’re not appropriately emptying your stomach and that means that the food stays in there longer, causing a fullness sensation and more risk of reflux.”
Blood sugar: There has been some research showing a possible link between apple cider vinegar and better control of blood sugar (glucose). One 2021 review published in the Journal of BMC Complementary Medicine and Therapies looked at clinical trials involving people with high blood sugar levels who were given vinegar orally. The reviewers concluded that ACV was tied to lower fasting glucose levels and slightly lower hemoglobin A1c (HbA1c) values, the average of blood sugar levels over several months.
One theory is that the vinegar may thwart blood sugar spikes by blocking the absorption of starches, delaying gastric emptying, and enhancing the body’s use of glucose. Vinegar might also slow the digestion of complex carbohydrates, which may be a part of lowering average blood sugar, as well.
Keep in mind that ACV isn’t a treatment for diabetes or high blood sugar, and it’s important that you don’t overdo it. If you’re insulin-dependent or if you’re taking diabetic medications that reduce your glucose levels, vinegar may reduce your blood sugar levels even further, increasing the risk of hypoglycemia, a potentially dangerous condition, says Zylberglait.
Infections: Some studies point towards ACV’s potential ability to help cure infection. A 2021 study published in Scientific Reports linked ACV to preventing the growth of the bacteria E. coli and methicillin resistant Staphylococcus aureus (MRSA) in petri dish environments. But a petri dish is much different than a person, so the results may not be the same in humans.
If you think you have an infection, it’s important to see your healthcare provider (HCP), and keep in mind that antibiotics used to treat bacterial infection have been studied extensively.
Weight loss: While a few studies have shown a correlation between drinking ACV and weight loss, the research is still limited—and not many studies have been conducted in people.
In a small 2018 randomized clinical trial published in the Journal of Functional Food, researchers examined ACV and its effects on weight loss over a 12-week period. Each trial participant restricted calorie intake and exercised, but half also had 1 tablespoon of ACV with every lunch and dinner. In the end, people who consumed the ACV lost an average of almost nine pounds, while those who didn’t lost an average of five pounds. Since participants were also on a calorie-restricted diet and exercising regularly, however, it’s tough to determine whether ACV had much of an effect.
A more comprehensive 2022 review of 11 studies published in the European Journal of Integrative Medicine found there were some statistically significant—but still very small—reductions in body mass index and weight observed after people supplemented with ACV.
Other risks to consider
For most people, consuming small amounts of apple cider vinegar is safe, but there are some who should be careful. Those with kidney disease may have a hard time processing the extra acid. It may also influence potassium levels, which can also be of concern for individuals living with kidney disease.
If you’re taking diuretics, you may want to speak with your HCP before incorporating ACV in your diet. “The purpose of water pills, or diuretics, is to help your body clean out fluids, but when you eliminate fluids, you also eliminate some electrolytes that you have in your body—like potassium—that are important,” says Zylberglait. “Apple cider vinegar may reduce the level of potassium in your body, so if you’re using both, you may have low potassium levels, which can negatively affect how your heart and muscle function.”
Be mindful if you’re taking certain heart medications as well, specifically those for arrhythmia. “Again, because of the fluctuating potassium levels, you may increase your risk of arrhythmia, and this could have serious consequences such as cardiac infarcts, strokes, or death,” notes Zylberglait.
Some ACV options are considered unpasteurized because they haven’t been heated to 140°F to kill any remaining bacteria and yeast. People who are pregnant or have weakened immune systems should always steer clear of unpasteurized foods and beverages, since there’s a chance they could contain harmful bacteria like listeria. Check the labels on the bottle if you’re unsure.
If you want to begin consuming ACV daily, first speak to your HCP to learn how your medications or health conditions could be affected.
How to incorporate ACV into a healthy diet
Apple cider vinegar won’t work miracles and should never replace medical treatment. To prevent or manage health conditions, it’s better to practice healthy habits such as eating a well-balanced diet, maintaining a healthy weight, getting sufficient physical activity, and staying up to date on screenings. Always talk to an HCP if you’re concerned about unusual symptoms.
That said, a small amount of ACV may be okay for some people and can add low-calorie flavor to your diet. When using ACV in a daily drink, it’s best to dilute it, since the acid in the vinegar can damage your tooth enamel. The ratio should be 1 teaspoon of vinegar to 8 ounces of water or other liquid. Better yet, try splashing your salad with vinegar and olive oil, rather than choosing creamy dressings high in sugar, salt, and fat.
Remember that ACV can’t erase the effects of unhealthy eating or chronic conditions. “With larger, longer-term studies, we may discover that ACV is really beneficial, but at this point it's hard to say,” says Zylberglait. “I’m not against incorporating apple cider vinegar into your diet, but as far as using it as medication, we don't have enough information to do that.”
Overall, using ACV in certain circumstances may be helpful. While it isn’t a cure-all, it is likely not harmful if used in small doses. As always, if you are curious about whether ACV would be helpful for you, it is best to consult your HCP.
