Apple Cider Vinegar - And a Perspective on "Real Science"

During a recent conversation, a friend who helps run a health coaching company said “A medical reporter gave a segment on TV last night about apple cider vinegar, and now our coaches’ phones are ringing off the hook. We need a point of view, stat!” So I decided to write one. The “folk medicine” characteristic of apple cider vinegar (ACV) then prompted some reflections about Western medicine’s gold standard for “real science”: the Randomized Controlled Trial, or RCT. But first, a point of view (often shortened to POV) on ACV.

A Point of View on Apple Cider Vinegar

What is ACV? From Wikipedia: "Apple cider vinegar...is a type of vinegar made from cider or apple must and has a pale to medium amber color. Unpasteurized or organic ACV contains mother of vinegar, which has a cobweb-like appearance and can make the vinegar look slightly congealed. ACV is used in salad dressings, marinades, vinaigrettes, food preservatives, and chutneys."

Common Uses: an ancient folk remedy, cited as useful for hundreds of conditions. Very few have been studied and verified in randomized controlled trials.  See this easily readable article for a list and discussion of common attributed remedies or uses. The article quotes Dr. Carol Johnston, a leading researcher in this area; see the reference to one of her papers below. Common uses discussed include:

• Controlling diabetes (Johnston says a causal link is not yet indicated.)
• Losing weight (one study shows a modest benefit)
• Teeth cleaning (a dentist says “Don’t”)
• Skin, hair, and nails (dermatologists say there are some benefits, but be careful)
• And many others…

Pros: It can help regulate blood sugar. Dr. Johnston was the principal investigator of this published study: Vinegar ingestion at mealtime reduced fasting blood glucose concentrations in healthy adults at risk for type 2 diabetes. Journal of Functional Foods 2013; 5: 2007–2011   

Downsides:  Few noted, if diluted with water and not overused. Of course, interactions with medications should be checked. Without dilution, it can irritate the esophagus and the lungs if inhaled. Dilution helps mitigate the sour taste as well.

Dosage often cited: 1 tablespoon, diluted, with meals or before bed. Use raw, unfiltered, unpasteurized, organic ACV. Bragg is a popular brand.

Summary: ACV can help regulate blood sugar, which in turn has beneficial effects. There are many other uses, but do your own research, and remember that almost all recommendations include dilution. From a Western medicine perspective, most uses are folk remedies at this point, but some are being studied such as ACV in cold prevention. While they may not be “scientifically proven” via the standard of an RCT, some uses may still be therapeutic either directly or through placebo effect.

Reflections on Randomized Controlled Trials (RCTs)

Many MDs in the U.S. would say any beneficial effects of nutritional therapies are not “scientifically proven” because the gold standard RCT has not been rigorously designed, carried out, published in a peer-reviewed journal, and replicated. But should that stop you from using all such “unproven” therapies?

RCTs attempt to isolate one variable (e.g. one chemical compound, one drug, one behavior modification, etc.) so that efficacy can be proven and any side effects uncovered. It makes sense, of course, but perhaps not as the only standard for all development.  Humans are extremely complex. Isolating a single variable can be very difficult, and by design ignores many complex interactions.  This is particularly difficult in nutrition science. For instance, there are millions of interactions among the various macro- and micro-nutrients each person ingests. And these interactions occur within each person's individual biology, environment, stress levels, and on and on.

We always want a silver bullet, and most research funding comes from pharmaceutical companies that want to own the next big one. Despite decades of RCTs, we still have no silver bullet for dementia – perhaps we need to use another scientific model that better recognizes complexity.

One of my relatives has three degrees from world-leading universities, and has suffered from severe asthma for decades. He’s on four meds daily. I’ve told him that thousands of asthmatics deal very successfully with their condition through nutritional approaches, but he won’t buy it. It just isn’t “scientific.”

Should you use ACV? Do some of your own research, and decide if you’d like to try. It may or may not help, but it is unlikely to cause harm if you follow guidelines, such as dilution.

And here’s the standard and valid warning: check with your licensed medical provider before undertaking any major changes in your health regime. For instance, what if there is a detrimental interaction between ACV and a med you are on? Your licensed provider might say “Sure, try some ACV for that; it may or may not work. Let me know.” Or you might hear "Not while you are on xyz. Let's try something else."

But if he or she says “Treating illness with food (or acupuncture or chiropractic or meditation or a ketogenic diet…) is quackery”, you have two choices: follow that advice, or find a new provider.

And that’s my POV on ACV and RCTs!