Vinegar can be made from just about any fermentable carbohydrate source, including apples. To make vinegar, yeast ferments glucose into alcohol, which in turn is converted by bacteria into acetic acid. The acetic acid concentration in commercially available vinegar is about 4-7%.
Lately, there is quite some hype around Apple Cider Vinegar. But why?
What are the Benefits of Apple Cider Vinegar?
Apple cider vinegar has recently been marketed in the mainstream media as the miracle cure for just about everything. From weight loss to cancer and detoxification, everything was in place and it seemed like you just needed to consume some apple cider vinegar – and all the problems would be solved.
The first question I ask myself about such claims is, “Where is the evidence?”
To answer this question, I entered the scientific literature on apple cider vinegar (and vinegar in general) to find out which of these claims have scientific backing and which are not. This article is a summary of the currently available evidence on a variety of apple cider vinegar benefits.
13 Benefits of Apple Cider Vinegar
The influence of vinegar on blood sugar has been studied extensively. Studies in rats have shown positive effects on glycemic control of both vinegar and cider vinegar.
In humans, the consumption of vinegar together with a carbohydrate meal reduced the blood sugar reaction by about 20-30%. However, it should be noted that the total area under the curve (AUC) of the blood sugar reaction did not differ between the group consuming vinegar and the non-vinegar group 2 hours after the meal. This means that vinegar reduces blood sugar increase in the short term, but does not prevent glucose absorption, it only delays it.
In fact, vinegar has not been shown to interfere with carbohydrate absorption. Instead, it has been shown that consuming apple cider vinegar or regular vinegar (mostly rice vinegar) reduces the rate of gastric emptying.
Although vinegar appears to reduce the acute glycemic response to food, it should be noted that the relevance of the glycemic index and blood sugar response as a result of a meal is strongly doubted by non-diabetics.
Although more research is needed in this area, it seems that consuming vinegar together with high carbohydrate meals reduces the glycemic response and may facilitate the control of blood sugar levels in diabetics.
In the fitness and health community, apple cider vinegar is often advertised as a weight loss agent. Fortunately, there are some scientific research that goes into this claim.
In humans, there was a non-significant trend that consuming vinegar together with a high glycemic meal was able to reduce calorie intake by 200 kcal the rest of the day. The reason for this was thought to be a decrease in gastric emptying rate due to higher saturation. However, there is evidence that the appetite-suppressing effect is more a result of nausea triggered by vinegar consumption.
To date, only a single study has investigated the effect of vinegar on weight loss in humans. Kondo et al. recruited 155 overweight Japanese subjects and given either 15 ml of vinegar, 30 ml of vinegar, or a placebo daily for 12 weeks. The weight loss was in a dose-dependent manner. The 15 ml group lost 1.2 kg, the 30 ml group 1.9 kg and the placebo group lost no weight, despite no differences in the report on their calorie intake.
One weakness of the study, however, was that the nutritional information provided to the participants was self-reported and we know that nutritional characteristics in overweight individuals are extremely unreliable and inaccurate.
Vinegar may be able to increase satiety to some degree (either due to delayed gastric emptying and/or nausea); however, a lot of research is needed before claims about weight loss can be made.
A variety of claims have been made regarding cardiovascular risk factors and mortality to be reduced with apple cider vinegar. However, the bulk of the data supporting these claims comes from rat studies and there are very few studies in humans.
In rats, apple cider vinegar consumption improved blood lipid levels and reduced oxidative stress. Black vinegar also reduced oxidative stress in rats. In addition, high doses of vinegar reduced blood pressure in an animal model with hypertension.
Observational studies on humans found a correlation between the consumption of oil and vinegar salad dressings and a reduction in mortality from cardiovascular disease in women. However, it is important to note that these individuals also delivered greater amounts of polyunsaturated fatty acids; It is therefore not clear whether the reduced mortality from cardiovascular disease was due to vinegar, polyunsaturated fatty acids or other factors.
In addition, no study has yet investigated the direct effects of regular vinegar on things like cardiovascular problems or mortality. Therefore, much more research is needed in order to be able to make statements about the effect of vinegar on a reduction of cardiovascular risk.
Recently, it has been increasingly claimed that apple cider vinegar has an effect on cancer risk; However, this claim does not enjoy much research support.
Studies from cell cultures and in animal models showed anticancer effects of vinegar. Observational studies in humans, however, gave mixed results; cancer risk increased or decreased as a result of vinegar consumption. So this claim cannot yet be considered confirmed.
Some allegations have also been made regarding the skin, resulting in apple cider vinegar, including: against acne, against wrinkles, for wound healing, for the removal of birthmarks, against the discoloration of bruises and much more.
To date, these claims are not supported by the research. Vinegar was ineffective for wound healing and lice control. In addition, attempting to eliminate moles with vinegar and prolonged exposure to vinegar sometimes led to chemical burns. Based on this, it is recommended to stay away from vinegar concerning skin treatment.
Oral Hygiene Benefits
Apple cider vinegar is supposed to benefit and whiten teeth and help against bad breath. Again, there is no supporting evidence for these claims.
Vinegar is acidic and, like any other acidic substance, can potentially degrade the enamel. However, there is indeed research showing that vinegar can be used effectively in the cleaning of teeth.
It is often claimed that apple cider vinegar is able to cure colds or reduce the duration of sore throats. The supportive evidence for this is scarce.
Much of the research on the antibacterial effects of vinegar focuses on its ability to eliminate pathogenic bacteria from food. Vinegar was also used as a cleaner, but it turned out to be less effective than commercially available cleaners.
In shrimp, high doses of vinegar (1-4% of their diet) increased the expression of genes affecting the immune system. However, the relationship between vinegar and the immune system, illness or sore throat has not yet been studied in humans. Already, esophageal injury has been reported as a result of the use of apple cider vinegar supplements. This led to a follow-up study, which found extreme variability in the composition of various apple cider vinegar supplements.
Benefits for Allergies
Apple cider vinegar is said to reduce a wide range of allergies. However, there are hardly any supporting studies. To date, only one study has been conducted on vinegar and allergies in humans.
In this study, the 7 subjects who had allergies to eggs, chicken, and lentils were subjected to a prick test to detect food allergies, with foods prepared either with or without white wine vinegar. The foods prepared with vinegar resulted in a reduced reaction during the prick test.
However, it should be kept in mind that vinegar is acidic and probably denatures the proteins of food in a similar way as it does in the stomach as part of the digestive process. It is therefore unclear whether the denaturation of the proteins by the vinegar before taking the food would have any other effect than the denaturation that occurs naturally in the stomach.
Apple cider vinegar is also claimed to benefit the inflammatory processes associated with arthritis or other inflammatory conditions. Again, there is not much research that proves this.
In an animal model with colitis, high doses of vinegar led to reduced inflammation, influenced positive bacterial populations, and accelerated weight loss. To date, these results have not yet been replicated in humans and there are no other data on humans supporting such claims.
There are some people who say apple cider vinegar improves fertility.
The only human study on this topic was a small study of 7 Japanese women who had a polycystic ovarian syndrome (PCOS) and thus had no normal menstrual cycle. After daily intake of 15 grams of vinegar for 90-110 days, 4 of the 7 women returned to their menstrual cycle due to the positive effect of vinegar on insulin resistance, which is often associated with PCOS.
However, much more research is needed to say that there is an effect of vinegar on fertility.
Detox diets based on the assumption that over time “toxins” accumulate in the body that need to be removed by dietary intervention are now becoming more and more popular. These diets often include apple cider vinegar, as it is said to help detoxify the body. However, an individual with a healthy liver and healthy kidneys is already well-positioned to remove chemicals from the body to prevent toxic levels from accumulating.
A recent literature review concluded that there was no evidence that detox diets removed toxins from the body. Thus, there is no evidence that apple cider vinegar or any other food would be able to remove toxins from the body.
It is often said that apple cider vinegar helps to shift the pH of the body more towards alkaline. However, the pH of the blood is controlled by the kidney to the most exact and kept in the range of 7.35-7.45. The slightest deviation from normal results in serious complaints, hospital visits and death.
Fortunately, there is no suggestion that human nutrition in individuals with a normal renal function would be able to significantly alter the pH of the blood, and thus there is no evidence to support this claim.
Other Benefits of Apple Cider Vinegar
There were many other claims about apple cider vinegar and its benefits for health. These include the reduction of reflux esophagitis (heartburn), the prevention of osteoporosis, the treatment of dandruff, an energizing effect, a reduction of convulsions, the fight against hiccups and much more.
To date, however, there is no evidence to support these benefits of apple cider vinegar.
Conclusion: Benefits of Apple Cider Vinegar
Many of the claims regarding apple cider vinegar and health are not supported by current scientific literature. There is evidence that eating vinegar can reduce the glycemic response to a meal and increase satiety. Individuals with diabetes or those who want to lose weight may, therefore, experience a small positive effect from the consumption of vinegar. At 3 kcal per teaspoon, vinegar consumes an insignificant portion of the total daily calories and can, therefore, be tested if you are in one of these situations.
The use of apple cider vinegar is also likely to have a positive benefit for health or weight loss. However, anyone who thinks apple cider vinegar alone is the solution to effectively lose weight will be very disappointed. There is no magic pill.
To control weight and optimize your health, the ultimate solution is to have a calorie intake that is right for your goals, to get those calories from nutrient-rich foods, to be physically active, and to maintain healthy body weight.