Apple Cider Vinegar

TL;DR

  • Apple cider vinegar is not a panacea, but it is a delicious ingredient in its own right, and there’s a good chance that it does help (albeit only potentially to a small scale) with the following:
    • regulation of insulin after a carb-heavy meal; and,
    • maintenance of a healthy lipid profile.
  • There are other potential benefits which seem somewhat plausible.
  • It is low risk for most healthy people, so long as you’re sensible about dose and concentration.

My Conclusion

I’m glad I did this research, because I feel like I’ve learnt enough to give me a level-headed attitude to the benefits of apple cider vinegar.

ACV was in my life as an ingredient before I was aware of these health claims and, now that I know about them, I’m going to go slightly further out of my way to incorporate it into my diet, particularly after carb-heavy meals.

I’m certainly not going to join the zealots though, with their habits of choking it down every evening and morning. I just don’t see the evidence that that’s the way to access the potential upsides, especially if you are otherwise healthy and have a good diet.

Apple Cider Vinegar – Overview

You don’t have to try hard to find bold claims about the benefits of drinking apple cider vinegar. I’ve been chugging the stuff myself, but I’ve decided to put my foot on the ball and do some research to find out if it’s simply a very successful meme, or whether there might be some substance to it.

Health Claims

Specific claims include that apple cider vinegar (in rough frequency order):

  • helps regulate blood sugar;
  • suppresses appetite;
  • improves heart health;
  • aids weight loss;
  • fights bacteria and viruses;
  • is nutritious;
  • aids digestion;
  • helps weak bones;
  • is good for throat/sinus problems;
  • helps clear up skin problems;
  • reduces heartburn;
  • reduces cancer risk; and,
  • fights bad breath.

And, as for risks:

  • leads to mineral loss in bones;
  • can interact with drugs;
  • can lead to burning in the mouth and oesophagus;
  • can mess with management of Type II Diabetes;
  • can cause nausea and indigestion;
  • can exacerbate ulcers;
  • can lead to dental erosion; and
  • can exacerbate Gastroparesis.

Bold claims, and potentially scary risks. This is why I want to be sure that it’s worth it.

Cancer

The boldest of all these claims needs to be addressed first, that drinking apple cider vinegar will help prevent cancer. It’s worth confronting nice and early that there is no substantive research to back up this claim.

The claim is based on an observation that cancerous tissue samples removed from rats and humans seem to grow more aggressively in acidic environments. Apple cider vinegar has been shown to have an alkalising effect (reduces acidity) in the body, hence making it less conducive to cancer growth.

Aside from a couple of small observational studies in China and Serbia there have been absolutely no substantial studies, in humans or rats, that I could find, that drinking ACV delivers this theoretical benefit in the body.

Extraordinary claims demand extraordinary evidence, and it’s just not there; however, if someone can point me in the direction of some compelling research then this benefit shoots to the top of my list and ACV becomes a big feature in my life.

Other effects in the body

The other specific claims (benefits and risks) can be grouped around core effects of drinking apple cider vinegar:

  • acetic acid (the second ingredient of ACV, by proportion, after water, at about 5%) improves insulin sensitivity;
  • reduces bad (LDL) cholesterol and triglyceride levels in the body, and increases good (HDL) cholesterol;
  • ACV is prebiotic and aids digestion;
  • ACV is nutritious;
  • acetic acid in high enough concentrations will burn body tissue; and,
  • acetic acid is antibacterial;

Acetic acid improves insulin sensitivity

The theory behind this claim is that the acetic acid in apple cider vinegar retains food in the stomach for longer. This has the effect of ‘levelling’ the rate at which food is delivered to the blood stream, which helps avoid insulin spikes and maintain the body’s insulin sensitivity (the loss of which is the cause of type II diabetes).

As well as smoothing out the insulin spikes, slowing the release of food from the stomach increases the duration after a meal in which you feel full, which reduces appetite.

Sound theory, and with some research to back it up. Unfortunately the trails that have been conducted have either been in rats (which offer a good but not perfect proxy for humans), or at a very small scale in humans (and so cannot be considered conclusive).

However, all of these trials were properly controlled, and were consistent with the theory, and with one another, so cannot be altogether dismissed. Lower postprandial glycemic load (glucose concentrations on the blood after a meal) was observed in these trials, but only to a significant degree if following a meal which had a high glycemic index (high in carbs and starches).

So, it seems likely to me that if you already avoid the fast carbs, then this is unlikely to make much incremental improvement to your insulin sensitivity or prolonged postprandial satiety. If, however, you can’t avoid them (either through willpower, or because you are at a social engagement and find it hard to find an alternative), then adding some apple cider vinegar to your meal might help. A side salad with a basic dressing of extra virgin olive oil and apple cider vinegar will be a discrete and delicious way to work it into the meal.

Those with type II diabetes should probably be careful though, as anything that messes with blood sugar concentrations should be carefully thought about. Probably best to consult a doctor.

Also, this effect might not be a good thing if you suffer from Gastroparesis, sufferers of which already have the problem that they retain food in the stomach for too long.

Reduces bad cholesterol and triglyceride levels in the body, and increases good cholesterol

As above, there is limited but promising research speaking to this claim. I’m not sure what the mechanism is behind the effect, but rat trials have observed significantly improved lipid profiles (decreased bad (LDL) and increased good (HDL) cholesterol) and lowered triglyceride levels (triglycerides are bad, because of ‘reasons’ [more research needed!]). This was true of both normal and diabetic rats.

And that’s just about all there is to say on that. There’s no doubt that having a more balanced lipid profile and reduced triglyceride concentration is a good thing, and drinking apple cider vinegar might do that for you (it seems to in rats).

However, it seems incredibly likely that, as compared to eating the right things (cut down on saturated fats and eat more salmon, etc.), the effect will be comparatively negligible. You can’t live on microchips dowsed in ACV and be ok. However, if your lipid profile is out of balance (high LDL/HDL ratio), this might put half a thumb on the scale in the right direction.

ACV is prebiotic and aids digestion

Note: prebiotic as opposed to probiotic. Probiotics (found in sauerkraut, kimchi, kombucha, Yakult, etc.) are ‘good’ bacteria that you want in your gut to help break down and release nutrients from your food. Prebiotics are food for these bacteria. When you eat prebiotics, you’re feeding your gut bacteria, which in turn feed you by processing your food efficiently.

Whereas most of these health claims are driven by the acetic acid content of apple cider vinegar, which is actually present in all vinegars and so there’s nothing special about the apple cider variant in these cases, the argument for vinegar as a prebiotic is particular to ACV.

The prebiotic bit comes from the murky swirly insoluble ‘chaff’ found in unfiltered apple cider vinegar (also called ‘the mother’). This is shown to be particularly delicious as far as your gut flora is concerned, and they’ll reward you for this delightful meal by thriving in your gut and doing a cracking job of breaking down your food efficiently and extracting all the goodies from it.

Seems plausible to me, and definitely worth adding to the list of delicious prebiotic foods I try to find opportunities to get into my diet.

ACV is nutritious

You only need to Google “apple cider vinegar nutrition” to see that this claim is a stretch. It’s pretty much zeros across the board, apart from a bit of potassium, iron and magnesium. If you’re particularly low on these nutrients you might look to ACV, but a postage-stamp-sized bit of kale is likely to give you much more than a shot of ACV.

That said, these definitely couldn’t be considered nutritionally empty calories, because there aren’t many of those either. It’s as energetically null as it is nutritionally null, all the good comes from the effects it triggers in the body.

And that’s not nothing – see above for the way in which ACV might indirectly boost the nutrition extracted from your broader diet.

There are also claims that ACV in high enough doses can leech minerals from your bones, which is ‘anti nutritious’, but I can’t see any evidence that this is a significant risk if you keep the doses sensible.

Acetic acid in high enough concentrations will burn body tissue

Yep. Chugging acetic acid neat will be very bad for you, as will putting it on your skin. Same goes to a lesser extent for concentrations around 5%, which is the typical concentration in apple cider vinegar. That discomfort you feel if you do drink it neat is your body trying to tell you something: “don’t do that again”. This is especially true if you suffer from stomach or gut ulcers.

Diluting it further and being sensible about how much you ingest in a day will mitigate pretty much all of the claimed risks of ACV consumption. You don’t need a lot (30ml spread across a day is probably plenty), and you should dilute it with water to at least 2:1 ratio. If it’s still uncomfortable, you need to dilute more. You can add a smidge of honey or other flavouring agents, but that’s down to preference.

Acetic acid is antibacterial

True that. This is what’s behind the claims that it will help soothe sore throats, etc.; clear up skin problem if applied topically; fight bad breath; and strengthen immunity.

The ability for ACV to kill bacteria on contact might make all of these claims plausible, except for the generic “strengthen immunity”. This feels like a real stretch, and is at odds with the prebiotic claims for ACV, suggesting that the bacteria in your gut will be fed by the mother, but killed by the acid.

Conclusion

I’ve always been a very low-level champion of apple cider vinegar, in complete ignorance of these health claims. It makes a nice salad dressing, and you can’t have a proper vindaloo without it. Reason enough.

All this gives me slightly more reason to make it part of my life.