Is kombucha beneficial?
Wednesday, January 30, 2019
Q “I was served a glass of kombucha. I didn’t want to look dumb, so I didn’t ask what it was. Can you tell me what it is and is it good for me?” JF, Greenville
A I smiled when I read your email, so many people could have sent your question. Although it’s a drink of early China, it’s only been commercially available in the U.S. for about 12 years. And since a large beverage company has started to make and distribute it, you will find it in all our local grocery stores as well as restaurants and coffee shops. Kombucha, pronounced (come-boo-chuh), is a fermented black or green tea beverage that is slightly acidic, sweet, and carbonated. Some find it refreshing. Before I turn the rest of this column over to Amanda Light, an ECU dietetic student, let me be clear that there are no published studies of benefits in humans and there are a few concerns. Here is other interesting information Amanda wants to share.
Read the ingredient label and you will find it contains tea, sugar or other sweetener, bacteria, and yeast. It is considered a probiotic -- live bacteria and yeasts that are thought to keep your gut healthy. Locally we would most often find them in yogurts or dietary supplements. Consumerlab.com analyzed several popular brands of Kombucha and found they contained 1.0 to 1.3 billion viable cells in 8 ounces — a bit lower than found in most supplements.
Of course, tea is known to have powerful antioxidant activity. Put the yeast and bacteria together, feed it with some sugar and you get a “tea fungus.” The tea fungus resembles the top of a mushroom, which explains why it is sometimes referred to as “mushroom tea.”
As the tea ferments, the yeast (most often saccharomyces) breaks down the sugar and converts it into ethanol or alcohol. Even though it is naturally occurring alcohol it should not be consumed by individuals avoiding alcohol because of pregnancy, allergies or sensitivities, religious beliefs or other reasons. To be sold as a non-alcoholic beverage it must be less than 0.5 percent alcohol by volume. A light beer is about 4.2 percent. To ensure the fermentation does not continue and increase the alcoholic content, keep Kombucha in the refrigerator.
It’s important to know that the health benefits that might come with regularly taking probiotic products are strain and dosage specific. There is great evidence that probiotics can help prevent diarrhea from infection or antibiotics and some improve Irritable Bowel Syndrome. But even for those conditions the exact strains and dosage are not known. We have so much more to learn.
One brand of Kombucha purchased locally just listed “bacteria cultures” on its ingredient label. Another brand listed bacillus coagulans and s. Boulardi with their cell count as the bacteria in the “culture.” At the moment, the Food and Drug Administration (FDA) has not approved any probiotics for the prevention or treatment of health problems. So, the assumption being made is that Kombucha with its good bacteria is helping digestion, absorption of vitamins and minerals, and overall health. The antioxidant properties of the tea are helping to prevent damage to cells in the body.
I have enjoyed a couple of different brands sold locally. Make sure you read the Nutrition Facts label when buying kombucha. The sugar content can range from 2 to 10 grams -- that’s up to 40 calories. There are lots of flavors like original, fruity, ginger and my favorite blueberry mint. When choosing one brand over the other, a lower sugar content is preferred, although taste may be your deciding factor.
In addition to concerns about the alcohol content, some health experts have worried about contamination. According to Consumerlab.com, commercial Kombucha products have had a good safety record. But you would want to know the source of your Kombucha and how it has been handled.
Again, while it is considered a relatively low calorie and safe beverage, the claims made on labels and on blogs and in articles about health benefits are all from rat studies. Those small studies show kombucha might stimulate the immune system; improve energy; enhance hair, skin, and nails; reduce risks for some cancers; improve liver function; reduce arthritis pain; help reduce symptoms of depression; improve cholesterol levels and lower blood pressure.
If you like to cook or brew, you might want to get a Kombucha starter kit, but take care to be very clean in your preparation of the drink. If you buy the starter or drink at a Farmer’s Market, ask questions about the safety and sanitation practices used by the vendor.
Professor emeritus Kathy Kolasa, a registered dietitian nutritionist and Ph.D., is an affiliate professor in the Brody School of Medicine at ECU. Contact her at firstname.lastname@example.org.