The Health Benefits of Vinegar
Apple cider vinegar and other types of vinegar have a long history of use in food and medicine (Ho 2017). Vinegar is produced from fermenting carbohydrates and can be made from grapes, rice, apples or other sources of sugars and carbs. Vinegar itself is sour from the presence of acetic acid and most commercial vinegars contain around 5-10%.
While claims exist for vinegar helping with kidney and gallstones, weight loss, irritable bowel syndrome, diabetes, infections, heart disease and even cancer, it’s worth seeing if there’s any evidence to support these beliefs.
One of the more common claims you’ll come across with vinegar is its effects on weight loss, but are they true? The evidence is limited, but still suggests that it may help. A Japanese study looked at daily vinegar doses of one or two tablespoons for three months. The one tablespoon group lost 2.6 pounds; the two tablespoons group lost 4.2 pounds. In addition, there was a significant change in superficial, abdominal and total fat surface area, meaning that subjects lost body fat, including detrimental belly fat (Kondo 2009).
Animal studies also suggest similar benefits. In rats prone to weight gain, vinegar prevented it, along with decreasing fat in the liver and abdomen (Yamashita 2016). Another study in rats also showed that vinegar blocked the accumulation of body fat (Konda 2009).
Studies on vinegar’s effects on cancer are very limited, preliminary and mixed. A study in China looking at risk factors for esophageal cancer found a 63% reduction in esophageal cancer with vinegar consumption (Xibin 2003). However, a Serbian study showed a 4.4 fold increased risk in bladder cancer risk correlated with increased vinegar use (Radosavljevic 2004). While these results raise some concerns, we need additional research to verify them, since the study used patient recall to assess dietary habits which isn’t always accurate (Shim 2014). It’s also possible that vinegar consumption was correlated with another factor, perhaps a common food or preservative found in vinegar preparations in Serbia.
In addition, preliminary in-vitro studies show vinegar can kill cancer cells in a petri dish. However, this is so far removed from the situation in a living person that it may not be meaningful (Okabe 2014). Animal studies using vinegar as a cancer treatment could start to show if there are promising effects.
Keeping blood sugar under control is a challenge for patients with diabetes. Limited research is starting to indicate that vinegar may be of some benefit. One study looking at patients with type 2 diabetes, prediabetes and normal controls showed that individuals with prediabetes had a 34% improvement in insulin sensitivity with vinegar. Type 2 diabetics had less of a response, but still improved 19% (Johnston 2004).
Patients with type 1 diabetes also saw improvements in blood sugar levels with vinegar after meals. Two tablespoons of vinegar with a meal containing carbohydrates decreased blood sugar levels after the meal by 20% (Miltrou 2010).
Overall, the data appears to indicate that vinegar helps lower blood sugar through a number of different mechanisms (Lim 2016). It’s also interesting that it appears to work better in keeping blood sugar down in people with normal blood sugar levels as compared to diabetics. Vinegar probably works best in slowing or halting the development of diabetes, rather than for the treatment of diabetes, but more research is needed to know for sure. Additionally, it’s also worth noting that vinegar can worsen gastroparesis, a condition that slows stomach emptying often associated with more severe diabetes.
It may seem strange, but people seem to get improvement in heartburn symptoms with apple cider vinegar before meals. The idea is that the sphincter at the bottom of the throat before the stomach is acid sensitive. When exposed to acid, this sphincter closes. In people with less stomach acid, the signal to close is weakened allowing stomach contents into the throat causing heartburn. Vinegar is an acid so it helps signal to the sphincter at the bottom of the throat to close and stomach contents stay where they belong in the stomach.
The minimal research that has been published around this idea has mostly been ignored. A comprehensive review of how the lower throat sphincter works didn’t mention acid at all (Mittal 2006). However, an earlier study on human subjects showed that acid caused significant contractions of the esophagus and they hypothesized the presence of acid sensors that were involved in the muscle activity of the throat (Bontempo 1994).
From clinical experience, I’d estimate that between a third and half of people with heartburn benefit from vinegar. However, a smaller portion have the opposite effect and vinegar makes their heartburn worse. Anyone that has increased burning or pain with the consumption of vinegar for heartburn should stop using it.
While I’ve considered apple cider vinegar for other indications including gallstones and irritable bowel syndrome, the evidence is thin to non-existent. That doesn’t mean it doesn’t work, it just means we don’t have any research to guide us. We do know that vinegar is a reasonable antimicrobial, meaning it can kill mold and bacteria, which is why it’s been used historically for preserving/pickling vegetables and other foods.
And just because vinegar is natural, does not mean it is perfectly safe. Recently at a local grocery store I found a bottle of apple cider vinegar that recommended drinking half the bottle (one cup) a day to help “detox” your body. That is WAY too much vinegar. In large quantities, vinegar can lower blood levels of potassium which in extreme cases could cause death.
In addition, since vinegar is acidic, if used undiluted it can erode tooth enamel and damage or burn your throat. It’s a good idea if you’re using vinegar regularly to drink it through a straw and wash your mouth out with pure water afterwards. If you’re using it long-term you may even want to rinse your mouth with a little baking soda added to the water to neutralize the acid preventing the loss of tooth enamel. I personally don’t recommend drinking vinegar straight, it should always be diluted.
How to Use Vinegar
Of the different forms of vinegar, raw vinegars without added sugar likely have the most benefit. Some of the effects, like weight loss appear to come from the acetic acid content itself, so even normal kitchen vinegar still carries some of the medicinal qualities. When using vinegar, keep in mind it’s best taken before or with a meal. Generally, I recommend at most one tablespoon twice daily in a cup of water before your two biggest meals. You can also use it to season foods or in salad dressings with likely the same benefits.
Vinegar is an interesting, inexpensive treatment and when used properly, has its place for potentially helping with a number of different health conditions. In the future, I hope we get more research to better understand the full potential of its benefits.