While a few lab and animal studies have shown promise, research on whether apple cider vinegar has a therapeutic effect on cancer in humans is lacking.

What Is Apple Cider Vinegar?

Apple cider vinegar is a type of vinegar that’s made of apples fermented with yeast and bacteria. It has a strong, sour taste and smell. Apple cider vinegar contains an acid called acetic acid. The acetic acid is what some people think may have an effect on cancer. Apple cider vinegar also contains polyphenols, which are antioxidants that may lessen cell damage that can lead to diseases like cancer. What Are the Claims About Apple Cider Vinegar and Cancer? Many of the claims about apple cider vinegar and cancer trace back to the work of scientist Otto Warburg, who won the Nobel Prize in 1931. Warburg believed that cancer grows more aggressively in an acidic environment, though this idea was somewhat controversial at the time in the medical community. What Does the Research Say About Apple Cider Vinegar and Cancer? Most studies on apple cider vinegar and cancer have been done on animals or tissue samples in a lab. “There is no known benefit to people with cancer using apple cider vinegar,” says David Kiefer, MD, medical director for the Integrative Health Clinic and a clinical assistant professor for the department of family medicine and community health at the University of Wisconsin in Madison. In a large observational study out of China, researchers found lower rates of esophageal cancer in people who frequently consumed vinegar, beans, and vegetables. The vinegar the participants in this study consumed was likely rice vinegar, however. Another study suggested that vinegar might actually raise a person’s chances of developing cancer. In that study, researchers found that consuming liver, canned meat, pork, and vinegar increased the risk of bladder cancer. The link between an acidic environment and cancer is not entirely clearly. Findings from an older study, published in 1996, suggested that human melanoma cells may grow and spread more quickly in an acidic environment. This study was done in a lab. Other research has shown an alkaline diet to lower acidity in the body does not prevent or treat cancer. Most researchers have concluded that there’s not enough evidence to show that changing the acidity level in your body by drinking a substance such as apple cider vinegar affects your cancer risk. According to the American Institute for Cancer Research, foods have little effect on a person’s pH levels, which the body controls naturally. “Altering the cell environment of the human body to create a less-acidic, less-cancer-friendly environment is virtually impossible,” the organization states. “I do not recommend apple cider vinegar for any specific purpose for people with cancer,” says Lise Alschuler, ND, a professor of clinical medicine and assistant director for the Fellowship in Integrative Medicine at the Andrew Weil Center for Integrative Medicine in Tucson, Arizona. Other Uses for Apple Cider Vinegar While apple cider vinegar isn’t a proven cancer treatment, it may help other medical conditions. “There may be some benefits with people with diabetes if apple cider vinegar of approximately 5 percent acetic acid is consumed in small amounts (about 1 teaspoon) with meals, but these studies should be repeated before a routine recommendation can be made,” says Dr. Kiefer. While more research is needed, other possible uses for apple cider vinegar may include:

Lowering cholesterolLosing weightReducing bacteria growth

How Do You Take Apple Cider Vinegar? Recommendations vary, but most people can safely consume up to 1 to 2 tablespoons of apple cider vinegar a day. It’s a good idea to start with a smaller amount to see how your body tolerates it. Apple cider vinegar may be added to a cup of water or tea to dilute it. It also comes in the form of capsules and tablets, which may be easier to take. “Some tablets could contain high levels of acetic acid that could be dangerous,” says Kiefer. “Some experts recommend against the use of apple cider vinegar tablets, primarily due to the lack of study supporting their use and because of safety concerns.” With respect to products on the market, there is a wide variety in the concentration of acetic acid in different brands. “Check a third-party certification entity for products that have been tested and found to contain adequate and/or safe levels of acetic acid,” says Kiefer. Warnings About Apple Cider Vinegar Some possible side effects of apple cider vinegar include:

Tooth Decay Too much apple cider vinegar can erode tooth enamel.Nausea or Digestion Issues In people with gastroparesis, apple cider vinegar could make digestion worse.Burning Throat or Skin You may want to dilute the apple cider vinegar with water to avoid this symptom.Low Blood Sugar People with diabetes could develop dangerously low blood sugar when taking apple cider vinegar.Low Potassium Levels When taken with some high blood pressure medicines, apple cider vinegar could cause potassium levels to drop too low.Allergic Reaction Some people are allergic to apple cider vinegar.

The Bottom Line While some animal or lab studies have shown that apple cider vinegar may have an effect on cancer, the research in humans is inconclusive. Be sure to talk to your doctor before trying any type of alternative treatment, including apple cider vinegar. Never use apple cider vinegar as a replacement for standard cancer therapy.