Apple Cider Vinegar Side Effects: What You Need To Know

Written by: Brilliant Staff

Fact checked by: Jessica Guht, M.Eng. Biomedical Engineering

Apple Cider Vinegar Side Effects: What You Need To Know

Apple Cider Vinegar (ACV) has gained significant attention in the health and wellness community, credited with potential benefits like weight management, gut health, blood sugar regulation, and more. However, despite long-standing use and popularity, scientific research into ACV is still in its infancy, and evidence of potential benefits — and side effects — deserve further study. This article delves deep into what we know so far about the benefits and side effects of apple cider vinegar, and tips for safe consumption.

The Science and Process of Creating Apple Cider Vinegar

Apple cider vinegar is created through a two-step process. First, the naturally occurring yeast in apple juice converts sugar into alcohol. Next, a bacteria culture called “the mother” is formed during a second fermentation process, which converts the alcohol into acetic acid.

Acetic acid is a potent acid known for its pungent smell and strong, sour taste, and it’s what gives vinegar its defining characteristics. Anecdotally, acetic acid is the driving force behind many of the health benefits attributed to ACV. As an acid, it’s particularly adept at killing certain strains of “bad” bacteria, including those living in the gut that can cause a range of digestive issues. But like any substance, good or bad, acetic acid can also lead to ill effects when consumed in excess or improperly.

Digestive Issues

One common side effect of consuming ACV is digestive discomfort. ACV is believed to slow down the stomach's emptying process, and while this could potentially help control blood sugar levels by preventing a rapid glucose influx into the bloodstream, it could also lead to feelings of nausea. Paired with the potent sour taste of ACV, it’s not unusual for people to feel queasy after and sensitivity. 

Furthermore, for those with gastroparesis, a condition in which the stomach cannot empty in a normal way, delayed gastric emptying can cause symptoms such as upset stomach, gas, bloating, or heartburn. 

In rare cases, ACV can also cause diarrhea. The acetic acid in ACV may cause the body to purge itself of unnecessary elements, leading to such a scenario. This is particularly concerning for people with a history of irritable bowel syndrome, peptic ulcers, or similar gastrointestinal disorders.


If you're new to ACV, your best bet is to start small. Begin with a small amount, usually half a teaspoon to a teaspoon diluted in a glass of water. Monitor your body's reaction post consumption, adjusting the dosage as needed. Remember to hydrate, especially if you experience symptoms like diarrhea or nausea.

Tooth Enamel Erosion

Your oral health, particularly your teeth, is another victim of ACV's high acetic acid content. Consistent exposure can lead to erosion of tooth enamel — the hard, protective layer on our teeth — leading to increased risk of cavities, tooth discoloration, and sensitivity. In terms of impact, it’s on par with excessive consumption of soda or citrus fruits. 


To safeguard your oral health, it’s important to dilute ACV in water before consuming, about 5 to 10 parts water per 1 part ACV. After consuming, rinse your mouth with water to neutralize the acid and wait for at least 30 minutes before brushing your teeth, as they may still be sensitive. Using a straw while drinking ACV can further limit its contact with your teeth, minimizing erosion risks.

Changes in Blood Sugar & Potassium Levels

Having a stable blood sugar level is vital for overall health and well-being. While some studies suggest ACV may help regulate blood sugar levels, excessive consumption may result in hypoglycemia, or low blood sugar levels, specifically for people already on diabetes medications. 

Consuming large quantities of ACV over the long-term can negatively affect individuals with existing low potassium levels. As an electrolyte, potassium is essential for proper nerve function, nutrient transport, and muscle relaxation and contraction — all of which can be adversely affected by low potassium levels. 


Before incorporating ACV into your diet, consult with your healthcare provider, particularly if you're on diabetes medication or have a history of electrolyte imbalances. Ensure to routinely monitor your potassium and blood sugar levels if you're consuming ACV regularly, more so if you're at a higher risk of developing electrolyte imbalance or if you have diabetes.

Skin Irritation

ACV has recently become a popular home remedy, used as a topical solution to address a variety of skin conditions, including acne, warts, and sunburn. While ACV can potentially help maintain skin pH due to its acid content, if applied in undiluted form, it can cause skin irritation, burns, and redness.


ACV should always be diluted in water before applying it to the skin. Conduct a patch test on a small area of your skin to ensure compatibility. If any irritation occurs, immediately discontinue use and consult a dermatologist.

Interaction with Medications

Apple cider vinegar can interact with certain medications, leading to adverse effects. For example, when combined with diabetes medications, ACV can enhance the blood sugar lowering effect, potentially bringing blood sugar levels down to a dangerous level.

Similar issues can occur when ACV is consumed by people taking diuretic medications, known to increase urine output to get rid of excess fluid in the body. Such medications can deplete potassium levels in the body.


Consult with your healthcare provider before adding ACV to your diet, especially if you’re taking medication for a chronic condition or have concerns about potential interactions.

Safety Guidelines for Apple Cider Vinegar Consumption

To maximize ACV's potential benefits while minimizing potential side effects, consider the following:

  1. Choose the Right Type of ACV: Opt for raw, organic, unfiltered apple cider vinegar containing the "mother." The "mother" is a cloudy substance residing at the bottom of the bottle, believed to be a rich source of proteins, enzymes, and beneficial bacteria.
  2. Dilution is Key: Heavily dilute ACV with water before consuming or applying it. The general recommendation is one to two tablespoons per cup (8 ounces) of water, or 5 to 10 parts water per every 1 part ACV. However, the proper dilution may vary depending on individual tolerance levels and use. When applying on the skin, an equal ratio of water and ACV is usually recommended.
  3. Monitor your Body's Response: Always be attentive to your body's reaction after consuming or applying ACV. If you experience any adverse symptoms, adjust the amount or frequency. In some cases, you might need to stop using it altogether.
  4. Seek Professional Advice: Always consult a healthcare professional before incorporating ACV into your regular diet, particularly if you have a pre-existing medical condition, are taking medications, or are pregnant or breastfeeding. Trustworthy guidance from medical professionals can help ensure that ACV is safe and beneficial for you to use.
  5. Maintain a Balanced Diet and Lifestyle: Remember, ACV is not a cure-all or a shortcut to better health. It’s a supplementary health product meant to be consumed alongside a balanced diet and an overall healthy lifestyle. Its potential benefits are best realized in conjunction with regular exercise, adequate sleep, balanced nutrition, and proper hydration.


While apple cider vinegar can offer a multitude of potential benefits, it is equally crucial to be informed about its potential side effects. By understanding how ACV interacts with our body and following the recommended safety guidelines, you can safely incorporate it into your wellness journey. Should you ever feel uncertain about its effects or potential interactions with your lifestyle, be sure to consult a healthcare professional.


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