6 Apr 2024

Apple cider vinegar: helpful or harmful?

4:49 pm on 6 April 2024

By Niki Bezzant*

Apple cider vinegar

Photo: Towfiqu Barbhuiya / Unsplash

If you're even mildly interested in health and you're on social media, you've probably seen someone promoting the benefits of apple cider vinegar (ACV). Since the 1970s, the vinegar made with fermented apples has been touted as a cure for everything from varicose veins to weight gain. Recently, a new crop of influencers has highlighted the ingredient as a way of lowering blood sugar. But are any of these claims true?

What's in apple cider vinegar?

Like other vinegars, ACV is a fermented product made with yeast and sugar. ACV, as the name suggests, uses apples as its base ingredient. The apples are crushed and yeast is added to boost the fermentation process; the sugar converts into alcohol and then bacteria break the alcohol down into acetic acid, which is what gives vinegar its distinctive flavour.

You can buy pasteurised and filtered ACV, or unfiltered 'raw' ACV which contains 'the mother' - a murky sediment of bacteria and yeast which, it's claimed, is the source of most of ACV's health benefits.

Does ACV have health benefits?

Considering the claims being made, there's surprisingly little good evidence of health benefits. Most of the human studies that exist on ACV have been small and come with the scientists' common refrain: more research is needed.

Healthline reports 'no studies support' any benefits of the mother in AVC.

That said, there are some other interesting findings.

ACV, like other vinegars, has antibacterial properties, and has been shown to kill pathogens including E.coli. So its traditional use as a food preservative has sound science behind it.

There's also research to show that ACV might lower blood sugar and bad cholesterol levels, with a 2021 review finding ACV consumption 'might beneficially affect glycaemic status and lipid parameters in adults'.

The researchers said, though, that these findings 'should be interpreted with caution', and that more study was needed.

A plate of salad

Adding apple cider vinegar to a salad dressing may result in a lower glycaemic index for the meal overall. Photo: Olivie Strauss / Unsplash

Specialist diabetes dietitian Kate Ellison echoes this and explains how it might work: "Acid lowers the glycaemic index (GI) of a food or meal, so adding something like a lemon juice or AVC vinaigrette dressing to a mixed meal like a rice salad for example, likely results in a lower glycaemic index for the meal overall."

That means the carbohydrate in the meal is digested and absorbed more slowly, leading to a lower blood glucose level after eating.

Ellison says the effect can't be guaranteed in everyone, though.

"Several factors influence GI - fat, fibre, starch, the physical form of food - and the GI is also different between individuals. So although acidity theoretically lowers GI, and some people may notice ACV reduces their post-prandial glucose levels; others may not experience the same level of benefit."

Weight loss is another area where there's interesting but not conclusive evidence of ACV's impact. Some small studies have shown ACV increases satiety and reduces appetite, which could lead to weight loss. A 2024 trial on 120 young people (aged between 12 and 25) who had obesity or were overweight found when the participants had 3 teaspoons a day of ACV for 12 weeks, they lost weight and body fat, had lower waist and hip circumferences, body mass index (BMI) and blood sugar, and lower cholesterol. Again, though, the researchers said longer studies are needed to confirm the findings and to understand why they happened.

Does ACV have potential health harms?

ACV is generally acknowledged as being pretty safe to consume. There are a few cautions though.

It might cause indigestion or acid reflux in some people, even though it's sometimes promoted as a cure for these. It's probably best not to consume ACV right before bed, to avoid nighttime upsets.

Drinking ACV straight is probably not great for teeth. It could erode tooth enamel, like other acidic foods. Diluting it might mitigate this.

ACV might also interact with some prescription drugs, so make sure you check with your pharmacist or doctor before starting drinking ACV.

Is ACV any good as a health tonic?

Ellison says she wouldn't recommend ACV as an overall cure-all for any health condition, including diabetes.

"Some people may believe they feel better after taking it, but this is highly individual, and does not provide evidence of wider health benefits", she notes.

For people with diabetes, she cautions: "if they want to add ACV to their diet or meals, that's OK. But not as a substitute for either a well-balanced eating pattern, or diabetes medications, both of which are foundations for effective diabetes management."

So: ACV is a nice addition to a meal as a dressing; it's useful for its antibacterial properties and might offer some health benefits - but it's not a miracle. Great for salad; not a superfood.

* Niki Bezzant is a writer, speaker, journalist and author focusing on health, wellbeing and science.

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