Can Apple Cider Vinegar Cause Diarrhea? A Comprehensive Guide

October 6, 2025 •

4 min read

According to anecdotal reports and some scientific studies, consuming too much or undiluted apple cider vinegar (ACV) can lead to digestive issues, including diarrhea. This effect is particularly noted in individuals with sensitive digestive systems or when an excessive amount is consumed in a short timeframe.

Quick Summary

This guide explains how and why apple cider vinegar can trigger diarrhea, covering the high acidity, its effect on gut bacteria, and individual sensitivities. It provides essential safe consumption practices and alternative remedies for digestive health.

Key Points

Acidity is the Main Culprit: The high concentration of acetic acid in ACV can irritate the digestive tract, especially if it is not diluted.
Dilution is Crucial: Always mix 1–2 tablespoons of ACV with at least 8 ounces of water to minimize the risk of digestive upset.
Start Slowly to Assess Tolerance: Beginners should start with a small amount of ACV to see how their body reacts before increasing the dosage.
Gut Bacteria Can Be Disrupted: Excessive ACV consumption can alter the balance of the gut microbiome, potentially causing digestive issues like diarrhea.
Individual Sensitivity Plays a Role: People with pre-existing conditions like IBS or sensitive stomachs are more likely to experience diarrhea from ACV.
Moderation Prevents Adverse Effects: Overconsumption, particularly if undiluted or on an empty stomach, is the most common cause of ACV-induced diarrhea.

Understanding the Connection Between Apple Cider Vinegar and Diarrhea

For many, apple cider vinegar (ACV) is a popular health tonic, but for others, it can cause uncomfortable digestive side effects, most notably diarrhea. The primary reason for this is ACV's highly acidic nature, driven by its main component, acetic acid. While this acidity can offer health benefits, it can also irritate the gastrointestinal tract and disrupt its delicate balance when consumed improperly.

The Role of High Acidity

The high concentration of acetic acid in undiluted ACV is a significant factor in causing digestive distress. When a person consumes ACV straight, or in large quantities, this intense acidity can lead to:

Stomach and gut irritation: The delicate lining of the stomach and intestines can be irritated by the strong acid, triggering a protective response that can result in inflammation and cramping.
Increased peristalsis: For some, the sugars within ACV can stimulate peristalsis—the involuntary muscle contractions that move food through the digestive tract. An increase in this activity can speed up bowel movements, leading to diarrhea.
Water-pulling effect: If consumed undiluted, ACV may pull water into the bowels from the body's tissues, resulting in looser, watery stools.

The Effect on Gut Bacteria

Although unfiltered ACV, which contains "the mother," is often praised for its prebiotic and probiotic properties, an overabundance can disrupt the gut microbiome's balance. The gut microbiome consists of trillions of bacteria that are crucial for healthy digestion.

Beneficial bacteria disruption: While ACV can target harmful bacteria, excessive amounts may also harm some of the beneficial bacteria necessary for proper digestion. This imbalance can lead to digestive upset, gas, and, in turn, diarrhea.
Temporary alteration: Any rapid or significant change to the gut's bacterial environment can cause temporary disturbances, which the body may react to with symptoms like diarrhea.

Individual Sensitivities and Existing Conditions

An individual's reaction to ACV is not universal. Some people are more sensitive to acidic foods and may experience digestive discomfort more readily.

Irritable Bowel Syndrome (IBS): Individuals with IBS are particularly prone to adverse reactions, as their digestive systems are already sensitive to certain triggers.
Gastroparesis: For people with this condition, where the stomach empties more slowly than normal, ACV could potentially worsen symptoms.
Pre-existing inflammation: Those with inflammatory conditions like gastritis or ulcerative colitis should be extremely cautious, as ACV can exacerbate existing inflammation.

How to Safely Consume Apple Cider Vinegar

Moderation and dilution are key to enjoying ACV's potential benefits without causing digestive upset. Here are the most effective strategies:

Dilute, dilute, dilute: Always mix 1–2 tablespoons of ACV in a large glass of water (at least 8 ounces). Never drink it straight, as this increases the risk of throat irritation, tooth enamel erosion, and severe stomach upset.
Start low and go slow: Begin with a small amount, such as a teaspoon, to see how your body reacts before increasing the dosage.
Consider consuming with a meal: Taking ACV alongside a meal can help buffer its acidity and support digestion, reducing the likelihood of stomach irritation.
Listen to your body: Pay attention to any signs of discomfort. If you experience nausea, cramping, or loose stools, reduce your intake or stop consuming it.

ACV Consumption: Side Effects vs. Safe Practices


Feature	Improper ACV Consumption (High Risk)	Safe ACV Consumption (Low Risk)
Preparation	Consumed undiluted or in high, concentrated doses.	Diluted properly with at least 8oz of water per 1-2 tbsp.
Timing	Often taken on an empty stomach, which can shock the digestive system.	Consumed with a meal to buffer acidity and aid digestion.
Quantity	Excessive amounts beyond the recommended 1-2 tablespoons per day.	Sticking to the moderate dosage of 1-2 tablespoons daily.
Immediate Symptoms	Nausea, stomach cramps, and irritation are common.	Mild to no digestive upset; potential for improved digestion.
Long-Term Effects	Potential tooth enamel erosion and low potassium levels.	No significant negative side effects if consumed properly.

Conclusion: The Balance Between Benefit and Risk

Ultimately, the question of "can apple cider vinegar cause diarrhea" has a clear answer: yes, it can, especially when overused or consumed improperly. The high acidity can irritate the digestive lining, disrupt the gut microbiome, and trigger faster bowel movements, particularly in sensitive individuals. However, for most people, incorporating ACV in a diluted form and moderate amounts is generally safe. By starting with a small dose, ensuring proper dilution, and paying close attention to your body's signals, you can enjoy the potential health benefits of ACV while effectively mitigating the risk of uncomfortable digestive side effects. Consulting a healthcare provider is always recommended if you have underlying digestive conditions or concerns.

For more detailed information on digestive health, the National Institute of Diabetes and Digestive and Kidney Diseases provides extensive resources on a wide range of conditions and symptoms. NIDDK Digestive Health.

Frequently Asked Questions

Apple cider vinegar can cause diarrhea due to its high acidity, which can irritate the stomach and gut lining. Consuming large, undiluted amounts can also disrupt your gut's bacterial balance and pull water into the bowels, resulting in loose stools.

To safely consume ACV, always dilute 1–2 tablespoons in a large glass of water (8 ounces or more). Starting with a smaller amount and taking it with a meal can further reduce the risk of digestive upset.

Yes, taking apple cider vinegar on an empty stomach can be a major trigger for diarrhea, especially for those with sensitive digestive systems. The direct exposure to the high acidity can be particularly irritating.

Most experts recommend not exceeding 1–2 tablespoons of apple cider vinegar per day. Consuming amounts significantly over this, particularly undiluted, increases the risk of digestive distress and other side effects.

Yes, in addition to diarrhea, ACV can cause bloating and gas. Some individuals find that it slows stomach emptying, which can lead to a feeling of fullness, bloating, and general discomfort.

While gummies may reduce the risk of tooth enamel erosion, they can still cause digestive issues like diarrhea if overconsumed. It's important to stick to the recommended dosage and monitor your body's reaction.

Yes, if you experience persistent or severe digestive issues like diarrhea, it is best to reduce your intake or discontinue use and consult a healthcare professional.