Apple cider vinegar mixed with water is a popular home remedy that some people use to try to treat digestive issues. Here is an overview of what the research says about the potential benefits and side effects of drinking apple cider vinegar and water for stomach health.
Quick Summary
In a nutshell, here is what science says about what apple cider vinegar and water does for your stomach:
- May help improve digestion – Acetic acid, the main active component of apple cider vinegar, may have beneficial effects on digestion by increasing stomach acid production.
- Can kill harmful gut bacteria – The acetic acid in apple cider vinegar has antibacterial effects and may help kill harmful gut bacteria.
- May relieve constipation – Some evidence suggests apple cider vinegar may help stimulate bowel movements and relieve constipation.
- May cause side effects – Drinking too much apple cider vinegar can cause side effects like tooth erosion, throat irritation, and low potassium levels.
How Apple Cider Vinegar May Improve Digestion
One of the main ways that apple cider vinegar is thought to benefit digestive health is by improving digestion. Here is how it may help:
Increases stomach acid
Apple cider vinegar contains acetic acid, which is a key component that may help improve digestion. Acetic acid has been shown to increase stomach acid production and acidity (1). Having adequate levels of stomach acid is important for proper digestion.
As we get older, our bodies naturally produce less stomach acid. Low stomach acid can cause symptoms like bloating, heartburn and improper breakdown of nutrients (2). Thus, using apple cider vinegar to support healthy acid levels may promote better digestion, especially in those with low acid production.
Slows stomach emptying
Studies show that vinegar can slow the rate at which food leaves your stomach after a meal (3). This delayed gastric emptying gives your body more time to break down food properly and absorb nutrients.
Slower stomach emptying may also help increase feelings of fullness after eating and prevent blood sugar spikes (4). Thus, drinking a bit of apple cider vinegar with water before meals may support healthy digestion and blood sugar control.
Kills Harmful Gut Bacteria
The acetic acid found in apple cider vinegar has antibacterial properties that may benefit gut health. Acetic acid has been shown to be effective at killing unwanted bacteria that can cause digestive issues, including E. coli and Staphylococcus aureus (5).
One study found that vinegar reduced numbers of certain bad gut bacteria in diabetic rats (6). Another study showed vinegar’s antimicrobial effects effectively killed bacteria like Salmonella and Escherichia coli O157:H7 (7).
By decreasing populations of harmful bacteria in your gut, apple cider vinegar creates an environment that allows beneficial bacteria to thrive. This balanced gut microbiome sets the stage for improved digestive health.
May Relieve Constipation
Drinking apple cider vinegar diluted with water may help provide relief from constipation for some people. A few reasons it may help stimulate bowel movements include:
- Increased motility – Acetic acid found in apple cider vinegar may increase motility in the intestines, helping contents move through faster (8).
- Softens stool – Apple cider vinegar can draw water into the intestines to help soften and ease passage of stool (9).
- Stimulates reflex – Vinegar may support the ileocecal valve reflex to stimulate movement and bowel contractions (10).
One study in rats with constipation found that those treated with apple cider vinegar had increased stool frequency and improved moisture content of stool, showing its potential to relieve constipation (11).
Mixing 2 teaspoons (10 mL) of apple cider vinegar into a glass of water and drinking it 1-2 times per day, such as before meals, is generally considered safe and may help provide constipation relief.
Potential Apple Cider Vinegar Side Effects
Although it can provide health benefits for many people, drinking apple cider vinegar can also come with some potential side effects, especially if you drink too much. Possible side effects can include:
Tooth erosion
Apple cider vinegar is very acidic, with a pH around 2-3. Acidic foods and beverages can erode tooth enamel over time. One study showed rinsing with apple cider vinegar for 2 weeks resulted in enamel loss (12).
To avoid erosion, dilute apple cider vinegar in water instead of drinking it straight. Also wait at least 30 minutes after drinking it to brush your teeth.
Throat irritation
Apple cider vinegar has high acidity. Drinking it straight can sometimes result in a burning feeling or irritation in the throat.
Diluting it before drinking can make it gentler on the throat. Start with a small amount like 1 teaspoon (5 mL) diluted in a glass of water and increase the dose slowly over time as tolerated.
Low potassium
There are a few reports of people experiencing low potassium levels after taking apple cider vinegar for long periods of time. It’s thought that the acetic acid may prevent potassium absorption (13).
Those with certain conditions like diabetes or taking potassium-lowering medications may be more susceptible to potassium depletion. Keep your intake in moderation and consider having lab work done periodically if you drink it regularly.
Drug interactions
There is potential for apple cider vinegar to interact with certain medications. The acetic acid may decrease potassium levels, compounding the effects of medications designed to lower potassium like diuretics or insulin (14).
Apple cider vinegar could theoretically decrease blood sugar and affect insulin requirements for diabetics, although evidence is limited on this (15).
Speak with your healthcare provider about potential interactions if you take any long-term medications.
How Much Apple Cider Vinegar to Drink
At low doses, few side effects have been reported with drinking apple cider vinegar. But higher intakes do pose a greater risk of negative effects.
Most studies showing benefits provided doses of around 1-2 tablespoons (15-30 mL) per day diluted in water. This is generally considered a safe starting dose when taken with meals (16).
You can gradually work up to larger amounts like 1-2 tablespoons 2-3 times per day based on your personal tolerance. It’s best to start slow and avoid drinking apple cider vinegar undiluted to minimize side effects.
Sample Apple Cider Vinegar Drink Recipe
Here is an easy recipe to make a drink combining apple cider vinegar, water and other optional ingredients:
- 1-2 tablespoons (15-30mL) apple cider vinegar
- 8 ounces (240mL) water
- Optional – Honey, cinnamon, lemon juice, etc. to taste for flavor
Simply mix all ingredients together in a glass. Stir well and drink once or twice daily, such as before meals. The amount of vinegar can be adjusted based on your personal tolerance.
The Bottom Line
Research suggests that drinking apple cider vinegar mixed with water may provide a range of digestive benefits. It can improve digestion, kill bad gut bacteria, relieve constipation and promote overall stomach health.
However, keep in mind that apple cider vinegar is highly acidic. Drinking too much can erode tooth enamel and cause throat irritation. Start with small doses diluted in water and increase slowly over time.
Overall, adding 1-2 tablespoons of apple cider vinegar per day into your diet may support better digestive function, especially when paired with a healthy diet high in plant foods and probiotics.