The Truth About Apple Cider Vinegar
Last week I posted an image to my instagram page , well to my stories, about the science behind (or lack thereof) drinking lemon water. If you missed it, essentially lemon water will hydrate you like normal water, no fancy detoxification happening. Anyway, in response I got an influx of messages saying “but ACV is different right?” or “yess I know, people should just drink ACV not lemon water”. For those that aren’t up with the lingo (I wasn’t), ACV is apple cider vinegar and if you haven’t heard it is the cure for all ailments, it will rid you of cancer, detox your body, make you lose weight and you will live happily ever after (I hope you are picking up on my sarcasm!).
So what better time to look at the evidence of ACV and see what truth there are to these claims.
ACV will help you lose weight - This claim arose from a study conducted about 10 years ago. The study showed in Japanese individuals a 30ml dose of ACV daily over 12 weeks led to weight loss. Now let’s break this down. Firstly, the study was poorly designed in that the food intake of these individuals was self reported (and we all know how inaccurate we are at reporting our own food intake). The weight loss achieved with ACV daily was a total of 1.7kg weight loss over 12 weeks so really not much (140g per week) and when they stopped taking the ACV within 4 weeks they had regained 1.3kg of the 1.7kg lost. So are we looking at sustainable weight loss? Not likely. The most important point here is that this study has not been replicated in the last 10 years. No one else has been able to show ACV helps weight loss. So until then I remain highly skeptical.
ACV suppresses appetite - This is somewhat true. Taking ACV has been shown to increase nausea in many individuals thus reduce appetite. Is this a good thing? I wouldn’t say so, nausea isn’t my favourite past-time. You know what else suppresses appetite without nausea? Healthy, high fibre, high protein food. What a great alternative!
ACV destroys tooth enamel - Due to the high acidity of ACV if taken without dilution it can erode tooth enamel and increase the likelihood of tooth decay, cavities and sensitive teeth. If you drink ACV at least dilute it in water.
ACV reduces your risk of cancer - There are only two studies that I could find that actually look at vinegar consumption and cancer in humans. One study showed vinegar was associated with an increased risk of cancer, one showed a decreased risk. There are a couple of studies done in petri dishes and rats which again still show mixed results. It should also be noted that these studies used a variety of vinegars, rice vinegar and cane sugar vinegar among others. I could not find a study that looked at the consumption of apple cider vinegar and cancer. Please let me know if such a study exists because I don’t know where the cancer reducing claims are coming from!
ACV lowers your blood sugar (thus insulin response) - This one is true, well has a degree of truth. Vinegar (any vinegar) can help to reduce the blood sugar response following consumption of high glycemic index foods. How? The acidity of vinegar delays gastric (stomach) emptying. Meaning food stays in the stomach longer. High GI carbohydrates typically leave the stomach quickly and are rapidly absorbed into the blood stream causing a spike in blood sugar and insulin. With vinegar added to the meal this process is slowed, meaning slower release of glucose from the carbohydrate containing food into the blood stream. Again, this function isn’t special to ACV, any vinegar will do this trick but it must be consumed with the meal, aka having vinegar first thing in the morning won’t affect your blood sugar at your meal 6 hours later.
ACV improves digestion - As a dietitian working with a lot of IBS clients this is something I hear frequently. ACV improves digestion. I tried my best to work out where this is coming from, what research do we have to show there is any benefit on digestion and I was left with nothing. Aside from what i’ve stated above in that ACV (or any vinegar) slows the emptying of the stomach, there doesn’t appear to be any evidence that ACV can influence digestion. Do some people find the delayed gastric emptying helps them? May be? In my experience a delayed gastric emptying can also contribute to bloating though as food is sitting in the stomach longer. So again I have no proof here that outside of slowed gastric emptying there is an effect on digestion. Again, if you have seen some good research on this, flick it my way.
ACV Detoxifies the body - There is no evidence that ACV can detoxify the body, in fact a recent literature review concluded that there are no foods, or diets that can detoxify your body. Your liver and kidneys are your detoxification organs, treat them well by eating healthy and drinking water and you have all the detoxification you need.
ACV alkalises the body - This I find is a bit of a cool topic lately. Eating to alkalise your body. What these alkalising diets, foods, supplements etc fail to recognise is that the pH (the acidity or alkalinity) of our blood is stable. It stays between 7.35 -7.45. If our pH goes outside this range we are in a very serious state of illness and you will find yourself in a hospital bed promptly and facing death. Fortunately though, foods or drinks can’t affect the pH of our blood like this, so you can rest easy knowing that your ACV isn’t going to alkalise your body.
ACV reduces inflammation and improves immunity - Vinegar can kill pathogenic bacteria in food, and can also potentially do so in our environment, hence why it is sometimes used as a cleaner. Some people then think this must mean it can kill bacteria in our body e.g. if we have a cold, flu or sore throat. This unfortunately isn’t true and ACV can actually cause injury to the oesophagus due to it’s acidity so probably not the best cold and flu remedy. When it comes to inflammation, we don’t have any human studies showing a reducing in inflammatory markers with ACV.
The bottom line:
ACV has a whole heap of claims with very little research. The main benefit is in it’s ability to slow gastric emptying thus reduce the blood sugar spike that occur with the consumption of high GI foods. So consuming some vinegar on your white bread may be a great idea, especially if you have insulin resistance. However this isn’t something that is limited to ACV, any vinegar will do this and in fact even adding fats or protein to a high GI carbohydrate will also delay gastric emptying and reduce the blood sugar response.
Are there risks in taking it? No, unless you drink it straight and damage your enamel. So the bottom line is, if you like drinking it, go ahead and drink it (diluted) but don’t think it is going to keep you alive, cure your illnesses or be your miracle weight loss solution. Personally, the thought of drinking vinegar is a little off putting but I do use it in a lot of home made salad dressings.
One more thing!
So I don’t ask of much from you guys but I have recently been nominated in the Bupa Blog Awards, I would LOVE it and be ever so grateful if you could pop on over here and vote for me. If you like my content and the message I share, it would mean the world to me. Thank you from the bottom of my heart! Vote here.
Please share this article with anyone you think would learn from it. Copy the link to facebook, or share on your instagram stories or profile. Don’t forget to tag me as I love seeing you share this. Let’s try and get some science back into the world of nutrition.
Kondo, T., et al., Vinegar intake reduces body weight, body fat mass, and serum triglyceride levels in obese Japanese subjects. Biosci Biotechnol Biochem, 2009. 73(8): p. 1837-43.
Radosavljevic, V., et al., Non-occupational risk factors for bladder cancer: a case-control study. Tumori, 2004.90(2): p. 175-80.
Xibib, S., et al., Risk factors for oesophageal cancer in Linzhou, China: a case-control study. Asian Pac J Cancer Prev, 2003. 4(2): p. 119-24.
Klein, A.V. and H. Kiat, Detox diets for toxin elimination and weight management: a critical review of the evidence. J Hum Nutr Diet, 2015. 28(6): p. 675-86.
Brighenti, F., et al., Effect of neutralized and native vinegar on blood glucose and acetate responses to a mixed meal in healthy subjects. Eur J Clin Nutr, 1995. 49(4): p. 242-7.
Johnston, C.S., et al., Examination of the antiglycemic properties of vinegar in healthy adults. Ann Nutr Metab, 2010. 56(1): p. 74-9.
Ostman, E., et al., Vinegar supplementation lowers glucose and insulin responses and increases satiety after a bread meal in healthy subjects. Eur J Clin Nutr, 2005. 59(9): p. 983-8.
Hlebowicz, J., et al., Effect of apple cider vinegar on delayed gastric emptying in patients with type 1 diabetes mellitus: a pilot study. BMC Gastroenterol, 2007. 7: p. 46.
Liljeberg, H. and I. Bjorck, Delayed gastric emptying rate may explain improved glycaemia in healthy subjects to a starchy meal with added vinegar. Eur J Clin Nutr, 1998. 52(5): p. 368-71.