Apple Cider Vinegar

Medically Reviewed by Jabeen Begum, MD on July 07, 2023
7 min read

Apple cider vinegar (ACV) is a type of vinegar made with crushed fermented apples, yeast, and sugar. It's used as an ingredient in foods such as salad dressings, pickles, and marinades.

For many years, people have also used it as a home remedy for everything from fighting germs to preventing heartburn. More recently, research has shown that apple cider vinegar might have some real health benefits, such as helping reduce blood sugar levels and aid weight loss.

While there's not a lot of evidence for these benefits, ACV is generally harmless – as long as you use it correctly.

 

Apple cider vinegar is made through a process called fermentation. The process has two steps. First, the apples are crushed and yeast is added to speed up the fermentation process, so the sugar converts into alcohol after a few weeks. Then, natural bacteria break the alcohol down into acetic acid, which gives vinegar its tangy taste and odor.

Most ACV you find in the grocery store is the clear, pasteurized, and filtered type. But, you can also buy raw, unfiltered ACV that contains a cloudy sediment. Called "the mother," this substance is made up of settled bacteria and yeast.

Some people give the mother credit for ACV's health benefits. And it's thought to contain small amounts of probiotics (healthy bacteria) that are good for gut health. But research hasn’t shown that the mother offers any particular health benefit.

The acetic acid in ACV is thought to be at least partly responsible for any health benefits it has. But other types of vinegar contain acetic acid as well.

You can also buy ACV pills, powders, or gummies. But there's been little research into whether these supplements have any effect. Because the FDA doesn't regulate dietary supplements, you can't be sure exactly what's in them.

 

Vinegar is an excellent source of:

Some types of vinegar can also be a good source of antioxidants. The darker the vinegar, the more antioxidants remain in the liquid. Darker vinegars are generally less refined than lighter vinegars, with healthy compounds in the liquid affecting taste and color. 

Most studies that support ACV for health effects have been small, and the results haven't been decisive. We need more and bigger investigations into its benefits. So far, here's what research has found:

It may help with weight loss. One study showed that taking apple cider vinegar twice a day helped people following a reduced-calorie diet lose a few extra pounds. But the study was small and short-term, following 39 people for 12 weeks.

Some researchers thought the vinegar's acetic acid might speed up metabolism, but the data didn't bear this out. It may be that people lost more weight because of the placebo effect. Or perhaps the acetic acid made them nauseated, which caused them to eat less.

It may lower blood sugar. Several smaller studies have reported that taking a tablespoon or two of apple cider vinegar could lower your blood sugar after meals. The effect was moderate, and we need more research to know exactly how it works. Keep in mind that vinegar can't replace diabetes medications and a healthy lifestyle, but it should be safe to add to your treatment plan.

It may lower cholesterol. The same small study that reported ACV boosted weight loss also found that it lowered the total cholesterol levels of study subjects who took it. It also increased their "good" cholesterol and lowered levels of triglycerides (fats in the blood). Other studies have had similar findings. Experts caution that we need more research to fully understand this link.

People also use apple cider vinegar for purposes that haven't been researched much or haven't been shown to be effective. Some of these uses include:

Lower blood pressure. One study in rats suggests that ACV could help with high blood pressure, but no studies donein humans back this up. High blood pressure can be a serious condition, so medical treatment and a healthy lifestyle are essential.

Ease acid reflux. Many people swear by ACV as a remedy for heartburn and acid reflux. But there's no research to prove it's effectiveness. Ask your doctor if you could try itto ease your discomfort. Start with small amounts, diluted in water.

Provide eczema relief. Some people with eczema use apple cider vinegar to ease their skin symptoms. But some studies reported that it had little effect and irritated some people's skin. Ask your dermatologist if it's OK for you to try it.

Kill germs. Though there's some evidence that ACV (along with lemon juice) can keep bacteria like Salmonella from growing on salad greens, it doesn't protect wounds against infection.

Improve hair health. Some people use it as a hair rinse to ease dandruff or remove product buildup. There's no proof it works for these things. But itdoes contain things that fight bacteria and fungi, which could promote hair health.

If you have hard water, apple cider vinegar may ease some of its effects. Hard water is high in minerals like calcium, magnesium bicarbonate, and sulfates. ACV is thought to help get rid of calcium buildup and leave your hair shinier when you use it after a shampoo.

It's safe and tasty to use ACV to add some excitement to your meals. Use it to liven up sauces and stews, as well as traditional salad dressings and marinades.

You can also drink it, diluted in hot or cold water as you prefer. Some people drink it before or after meals or before going to bed.

If you take an apple cider vinegar pill, tablet, powder, or gummy, start by asking your doctor how much you should take. Follow the package instructions, as dosages may vary by brand. Your safest bet is to look for brands with a stamp from the Banned Substances Control Group, Informed Choice, ConsumerLab, United States Pharmacopeia, NSF Certified for Sport, or NSF International.

If your doctor gives you the OK to try ACV for eczema, do a patch test first. Apply the vinegar to a small area of skin, then wait a few days to see if any irritation happens. You could then try it in:

  • A bath. Add 2 cups of apple cider vinegar to a tubful of lukewarm water. Soak for 15-20 minutes. Rinse your body well with cool water and moisturize with a scent-free lotion.
  • A wet wrap. Make a solution with 1 cup of warm water and 1 tablespoon of ACV. Soak gauze or pieces of clean cotton fabric in the solution. Put the wet cloths on your skin, then cover them with clean, dry cotton fabric. Leave them on for 3 hours or overnight.

To use ACV as a hair rinse, put it on your hair after you shampoo. Leave it in for 5 minutes and then rinse. Don't use it more than once a week, as daily use can dry out your hair.

Diluting ACV makes it less irritating to your scalp and skin. Some beauty websites suggest mixing ACV with equal parts water; others recommend adding 2-4 tablespoons to 2 cups of water. It's probably safest to start with a weaker solution.

Because we still have a lot to learn about ACV, there aren’t any official dosage suggestions. But some studies have given clues about the amount that may help with certain health conditions: 

Weight control. In the study that reported weight loss benefits, people drank about 2 tablespoons a day – one before lunch and the other before dinner. Experts say that amount should be safe for most people.

Blood sugar and cholesterol control. People in the study saw improvement when they took about 1½ tablespoons after a meal.

Acid reflux. A teaspoon or two diluted in a mug of warm water after a meal may help with your acid reflux. It's unlikely to make your condition worse.

Because it’s high in acid, it could irritate your esophagus (the tube that connects your throat and stomach) if you drink it straight or drink too much of it. Undiluted ACV can also break down tooth enamel.

To avoid these issues, always water down apple cider vinegar and drink it through a straw to protect your teeth. (ACV in food generally doesn't have these effects.)

ACV may give some people indigestion or make them feel nauseated. Don't drink it on an empty stomach, and if you feel sick or throw up after you take it, stop using it.

The vinegar can also interact with some drugs, such as diuretics, laxatives, and insulin. Always ask your doctor if it’s safe to use ACV with your current medications.

If you have low potassium levels (hypokalemia), too much apple cider vinegar could make the condition worse. That's because large amounts can reduce potassium levels. Avoid overusing ACV if you have kidney disease, since your kidneys might not be able to handle high levels of acid.

Because ACV is highly acidic, it stays safe to use for a very long time. But the taste and appearance can change over time, so it's best to use it within 2-3 years after you buy it.

You don't have to refrigerate apple cider vinegar once you open it. Instead, store it in a pantry or cabinet, away from direct sunlight. 

To keep it looking and tasting its best, store it in a glass or plastic container. Keep the lid on when you're not using it. And avoid letting moisture get into the container.