Apple Cider Vinegar and health - a review of the research

Organic Apple Cider Vinegar has proven health benefits including reducing blood sugar and lipid levels beyond those of standard acetic acid benefits with infection.

When I first started writing this review and checked out other sites, I couldn't believe how many websites and so-called ‘experts’ got their facts wrong (writes Oxford University Biochemist, Chris Woollams).

First, let’s be clear. For optimum health you need a slightly alkaline body, but an acidic gut.

I am not going to repeat or prove it all yet again. Instead read this simple explanation:

Go to: Why you need an alkaline body but an acidic gut

Now we have that clear, let’s turn to what is known about the benefits of vinegar and ACV in particular.

1. Apple Cider Vinegar (ACV) helps provide acidity to your gut.

When we were babies, we had a microbiome containing 98% Lactic ACID Bacteria (LABs). By age 50, most people’s LAB levels decline to just 4%. A group of your gut bacteria do make a short chain fatty acid called acetate, and this helps keep your gut acidic. An acidic gut improves digestion and absorption and keeps pathogens at bay. 

We suggest to patients that they squeeze a lemon or lime into a glass, add a good tablespoon of ACV, then add the total amount again as water. Start your days like this.

2. Apple Cider Vinegar - the fermentation of organic apples

Having your own ‘Vin aigre’ or sour wine is well established traditionally in families in France. One of my French friends gave me some of his ‘mother’ that had been handed down through the centuries in his well-to-do family, as long as I promised to only ever add top growth wine to it!  This was a great honour. The ‘mother’ is known by the French to be healthfull. 

Apple Cider Vinegar is the result of the fermentation of the sugars in crushed organic apples. The apples have their own ‘microbiome, and yeasts tend to inhabit the surface of organic fruit. First, yeasts ferment the sugar to alcohol and cider is formed, then the ethanol is converted to acetic acid in a second process by acetic acid bacteria (Acetobacter). The acetic acid is 5-6% of total liquid.

Research has isolated the bacteria from organic ACV - Acetobacter pasteurianus (71.90%), Acetobacter ghanensis (12.50%), Komagataeibacter oboediens (9.35%) and Komagataeibacter saccharivorans (6.25%). The yeasts isolated were Candida ethanolica, Pichia membranifaciens and Saccharomycodes ludwigii. There was a considerable difference between organic and processed ACV, with more organisms in the ‘mother’ of the organic (1). Interestingly, I can find no research which suggests ACV contains members of the families Lactobacillus of Bifidobacteria.

3. Fighting infection with vinegar and ACV

The use of vinegar to fight infections dates back to Hippocrates, and even to this day, vinegar and raw honey is still used as a poultice for ulcerations and sores. Acetic acid solutions at concentrations non-toxic to healthy cells are slightly effective at inhibiting the growth of Staphylococcus aureus and Pseudomonas aeruginosa bacteria (2). 

A 2005 study using vinegar and lemon juice on rocket salad and spring onions, showed it reduced levels of Salmonella typhimurium significantly (3). 15 minutes of the vinegar-lemon juice reduced the pathogen to undetectable levels. Now you know why the French make vinaigrette.

A 2021 study looked at Apple Cider Vinegar and methicillin-resistant Staphylococcus aureus (MRSA) and resistant Escherichia coli (rE.coli). Researchers showed ACV was capable of penetrating  microbial cell membranes and organelles, altering the expression of key proteins in the pathogens. Significant depletion of the two pathogens occurred (4).

4. Apple Cider Vinegar contains health compounds with benefits!

Of course the original organic apple juice contains the benefits of the fruit. Apples juiced and fermented on the skins, provide polyphenols, broken down pectin, quercetin, potassium,  vitamin C and B-vitamins and flavonoids, such as gallic acid, catechin, caffeic acid, and ferulic acid. The fermenting process concentrates the benefits of apples. Not surprisingly then, animal experiments have shown that ACV has a variety of benefits  including antioxidant, anti-inflammatory, anti-diabetic, anti-hypertensive, and anti-hyperlipidemic properties (7).

Vinegar is known to have certain health benefits, for example:

• Fighting Hypertension and blood pressure with vinegar

Research with rats showed a significant reduction in systolic blood pressure when consuming vinegar every day for 6 weeks. Researchers showed reductions in plasma renin activity and plasma aldosterone concentration (5). 

• Eating apples can reduce blood glucose levels and diabetes risk; so can using ACV

A 2018 study showed that there was a small but  significant reduction in mean HbA1c observed after 8 to 12 weeks of taking daily ACV (6).

• Eating apples helps weight loss and fat control; so can using ACV

Co-administration of ACV and a restricted calorie diet reduced triglycerides and increased HDL; it decreased body weight and BMI, and hip size (7)

• Meta-study shows benefit of ACV with lipid and glucose profiles

Researchers found that ACV consumption significantly decreased serum total cholesterol, fasting plasma glucose, and HbA1C concentrations in an analysis of 10 studies. In particular, researchers stated, “We found a significant favorable effect of ACV consumption on Fasting Plasma Glucose and blood lipid levels. (8)

5. Apple Cider Vinegar - concentrations matter

Researchers from South Korea decided to do an overview on the various benefits of ACV and concluded that ACV was ‘scientifically under-validated. The level (concentration) of ACV was crucial. For example at concentrations of 25% ACV had antimicrobial action but didn’t have strong anti-fungal activity - it didn’t kill candida and other yeasts. Yet, when the researchers checked  for cytotoxicity, ACV was effective as low as 0.7%. They concluded that it was wrong to make generalisations about the benefits of ACV (9).

This was confirmed by a dental study against bacteria - it concluded  pH mattered as well, not just the ACV concentration. Researchers studied the antimicrobial activities of commercially available 5% apple cider vinegar against Enterococcus faecalis, Streptococcus mutans, and Lactobacillus casei. All were killed but concentration and therefore pH were variables. Perhaps this is why such conflicting results occur?

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References

1. Comparison of Cultivable Acetic Acid Bacterial Microbiota in Organic and Conventional Apple Cider Vinegar; Aleksandra Štornik et al; Food Technol Biotechnol. 2016 Mar; 54(1): 113–119.

2.  Nonconventional topical therapies for wound care. Ostomy Wound Manage;  Rund CR.1996;42:22–24. [PubMed] [Google Scholar]

3. Effectiveness of household natural sanitizers in the elimination of Salmonella typhimurium on rocket (Eruca sativa Miller) and spring onion (Allium cepa L.); Ilkin Yucel Sengun, Mehmet Karapinar; Microbiol, 2005 Feb 15;98(3):319-23.

4. Antibacterial apple cider vinegar eradicates methicillin resistant Staphylococcus aureus and resistant Escherichia coli; Darshna Yagnik et al; Sci Rep. 2021 Jan 20;11(1):1854.

5. Antihypertensive effects of acetic acid and vinegar on spontaneously hypertensive rats. Kondo S, Tayama K, Tsukamoto Y, Ikeda K, Yamori Y.; Biosci Biotechnol Biochem. 2001;65:2690–2694

6. Diabetes Control: Is Vinegar a Promising Candidate to Help Achieve Targets? Fahad Javaid Siddiqui et al; J Evid Based Integr Med. 2018; 23: 2156587217753004. Published online 2018 May 14.

7. Beneficial effects of Apple Cider Vinegar on weight management, Visceral Adiposity Index and lipid profile in overweight or obese subjects receiving restricted calorie diet: A randomized clinical trial;Solaleh Sadat Khezri et al; Journal of Functional foods, Volume 43, April 2018, Pages 95-102

8. The effect of apple cider vinegar on lipid profiles and glycemic parameters: a systematic review and meta-analysis of randomized clinical trials; Amir Hadi et al; BMC Complement Med Ther. 2021; 21: 179. Published online 2021 Jun 29.

9. Authenticating apple cider vinegar's home remedy claims: antibacterial, antifungal, antiviral properties and cytotoxicity aspect; Judy Gopal et al; Nat Prod Res 2019 Mar;33(6):906-910.

10. The Efficacy of Apple Cider Vinegar at Different pH Values as an Antimicrobial Agent: An In Vitro Study; Prasanna Chandraseharan et al; J Contemp Dent Pract. 2023 Oct 1;24(10):779-786