Apple cider vinegar is an acidic, sour-tasting substance made from fermented apples. Crushed apples, water, and yeast sit at room temperature for at least 30 days. During this time, the yeast turns the sugars from the apples into alcohol. Bacteria then turn the alcohol into vinegar.
People have used apple cider vinegar for centuries to help flavor and preserve food. Today, many people claim that apple cider vinegar also has some medicinal properties.
In this article, we examine the evidence and discuss the potential health benefits of apple cider vinegar. We also cover possible side effects and how to use apple cider vinegar for health benefits.
Lowering blood sugar
Consuming apple cider vinegar may improve a person's blood sugar control.
High blood sugar levels can lead to a number of health problems. In particular, people who have type 2 diabetes need to keep their blood sugar levels under good control to avoid complications, such as nerve, kidney, eye, and heart problems.
Some small studies suggest that consuming apple cider vinegar may help improve blood sugar control.
The vinegar contained 6 percent acetic acid, which is similar to the amount in most apple cider vinegar. All the participants had impaired glucose tolerance, or higher than normal blood sugar levels.
A review of several small clinical trials found that people who consumed apple cider vinegar for 8 to 12 weeks experienced small reductions in their blood sugar levels.
Also, a meta-analysis found that people who took vinegar with a meal had lower insulin and blood sugar levels after a meal than the people who received a placebo.
Aiding weight loss
Again, a few small studies suggest that apple cider vinegar may help with weight loss.
For example, one study found that people who consumed apple cider vinegar along with a low-calorie diet lost more weight than those who followed the diet alone.
After 12 weeks of consuming 30 milliliters of apple cider vinegar each day, participants had lower body mass index and less belly fat and reported a smaller appetite than those who did not take the vinegar.
The researchers found that those who took apple cider vinegar each day also had a reduced appetite. However, another study challenges this last finding. Its authors state that vinegar simply caused nausea in people who took it, resulting in less desire to eat.
Cholesterol and triglycerides
Apple cider vinegar may lower cholesterol levels.
Some evidence suggests that taking apple cider vinegar could help lower both total cholesterol and triglycerides.
A 12-week study investigated the effects of taking apple cider vinegar in people on a low-calorie diet. The researchers found that participants who took apple cider vinegar not only lost more weight than those who took a placebo but also had lower triglycerides and total cholesterol.
The people who took apple cider vinegar also had significantly raised levels of high-density lipoprotein (HDL) cholesterol. Doctors sometimes refer to HDL cholesterol as "good cholesterol" because it can help lower the risk of heart problems.
Fungal infections can range from minor problems to life-threatening issues. Most commonly, people get fungal infections in the mouth, throat, and vagina.
People with type 2 diabetes may be at a higher risk of developing fungal infections, especially if they are not controlling their blood sugars levels well.
Candida albicans is a common cause of fungal infections in humans. In some people, Candida infections can be long-lasting and may become resistant to antifungal drugs.
Some research suggests that apple cider vinegar may have potential as an antifungal treatment.
One case report describes a man with type 2 diabetes who had a persistent fungal infection in the mouth due to Candida. The individual applied apple cider vinegar to the mouth twice a day for 7 days. After treatment, there was a 94 percent reduction of the fungal count affecting the mouth.
In another case report, a woman had chronic vaginal Candida for 5 years that did not respond to treatment. Applying apple cider vinegar cleared up the fungal infection.
A test tube study also found that apple cider vinegar, containing 4 percent maleic acid, can kill the Candida species that causes denture stomatitis, a fungal infection in the mouth that can happen when a person wears dentures.
Apple cider vinegar may also have antibacterial properties. One test tube study found that apple cider vinegar was effective at killing Escherichia coli and Staphylococcus aureus, which is the bacteria responsible for staph infections.
Another test tube study found apple cider vinegar was as effective as 5 percent sodium hypochlorite at killing Enterococcus faecalis. This bacteria occurs naturally in the bowel and gut of healthy humans but can cause serious infections.
Hair and skin care
Apple cider vinegar may improve hair shine and smoothness.
Many people use apple cider vinegar as a hair rinse to help improve shine and smoothness. While no studies have confirmed these benefits, the acidic nature of vinegar may lend itself to hair use.
One review suggests that alkaline hair products may cause hair to become damaged and frizzy. Applying apple cider vinegar, with its acidic properties, may improve the condition or appearance of hair.
Some people use apple cider vinegar as a skin toner or acne treatment, but there are no scientific studies to support these uses.
Side effects of apple cider vinegar
Tooth enamel is the hard outer surface of teeth. A person can wear down tooth enamel through excessive and harsh brushing. Consuming too many acidic foods and beverages can also cause damage.
Once tooth enamel is worn down, it does not grow back. Weakened or missing enamel leaves teeth prone to cavities and sensitivity.
Because it is acidic, regularly consuming undiluted apple cider vinegar by mouth can weaken tooth enamel. The acid in apple cider vinegar can also be irritating or damaging to the throat when taken frequently.
According to the United States National Capital Poison Center (NCPC), applying vinegar directly to the skin can cause burns and irritation. The NCPC list several reports of people requiring medical treatment after experiencing serious burns from applying vinegar, including apple cider vinegar, to the skin for long periods.
Apple cider vinegar can also burn and irritate the eyes, so people should use caution when applying it to the face, hair, and scalp. The NCPC do not recommend using vinegar to treat wounds.
How to use apple cider vinegar
Experts have not set safe or recommended amounts of apple cider vinegar for its various health uses. People should talk to a doctor first before using apple cider vinegar to treat a medical condition or for when using it in large quantities.
The safest way to consume apple cider vinegar is to use it in small amounts in food and dressings.
If consuming directly, diluting apple cider vinegar with water may be safer and gentler on the teeth and throat.
Try mixing 1 teaspoon of vinegar with at least 8 ounces, or a glass, of water. Take it no more than twice a day. People who find the taste unpleasant may wish to dilute it further.
People should stop consuming apple cider vinegar if it causes:
When using apple cider vinegar on the skin, apply it using a cotton ball and allow it to dry. Do not keep it on the skin with compresses, and apply it no more than once per day. Rinse it off immediately and contact a doctor if burning occurs.
Apple cider vinegar is a low-calorie way to add flavor to foods. While some small studies and case reports suggest that apple cider vinegar may have a number of potential health properties, many more large-scale studies are needed to confirm these benefits.
People should not use apple cider vinegar to replace medical treatments that a doctor recommends. They should always talk to a healthcare professional before using the vinegar to treat any condition.
Apple cider vinegar is safe when a person uses it in small amounts as a food flavoring or dressing. However, apple cider vinegar is acidic. Using the vinegar undiluted can damage teeth, irritate the throat and eyes, and causes burns on the skin.