Kombucha tea: Health halo or health hazard?

No matter what your opinions may be on kombucha, this trending tea has successfully made its way from health food stores into mainstream supermarkets creating a buzz among health enthusiasts.  It’s been touted to be the “elixir of life” professing to possessing healing properties boosting the immune system, dissolving digestive problems to curing cancer.  So, does it really have magical powers or are we being fed a bunch of goobledegook?

Before anyone jumps on the kombucha (almost sounds like an exotic dance, doesn’t it) tea bandwagon, let’s take a look at whether this drink lives up to its health halo reputation.

What is kombucha?

Kombucha, also known as kombucha mushroom tea, is a fermented tea that does not actually contain mushrooms.  Kombucha is made by mixing a culture of bacteria and yeast added to sugar, tea, and sometimes fruit juice and other flavorings.  The reference to being called “mushroom tea” is due to the brewing process when the bacteria and yeast blossom into a bubbly mass resembling a mushroom.

The tea has a slight effervescence and sweet-tart flavor and is highly acidic.  It contains sugar, B vitamins and antioxidants along with some alcohol which results from the brewing process.  Eight ounces contains just 30 calories, far below soft drinks. 

This tea has been around for centuries but only in the past few years has it become popular in the United States.  Its purported health reputation has been the main driver of its success as kombucha tea has rocked the beverage market – sales for 2015 were projected to be $500 million. It can be bought bottled either pasteurized or unpasteurized in various flavors. 

If you want to bypass buying kombucha at the store, you can be adventurous and brew your own by buying a culture starter called a “mother” and then ferment it in a clean jar for seven to 14 days.  If you intend to brew your own, it is highly recommended to study up on the proper technique and only under very sanitary conditions to avoid any issues with a food-borne illness.

How healthy is it?

To assess if kombucha tea is some sort of health drink with magical powers is hard to do as the benefits are mainly based on anecdotal evidence and only a few animal studies.  There are no clinical trials to substantiate the claims behind its health claims.  However, faithful followers using kombucha tea strongly believe it does aid digestion, boosts overall immunity and protects the liver.

Does it aid digestion?

There is a 2008 study that found the fermented tea provides antimicrobial activity controlling E. Coli and staph bacteria. Kombucha tea is rich in probiotics aiding our gut bacteria that have been shown to be beneficial for digestion.  The problem however, is kombucha’s probiotics are destroyed during the pasteurization process.  To drink kombucha unpasteurized is taking a food safety risk if it was not brewed in sanitary conditions, particularly for pregnant women or anyone with a weak immune system. 

There have also been reports of side effects if it is used excessively or has been contaminated.  Reports of stomach upset, acidosis, allergic reactions to mold that developed during fermentation  and toxicity from heavy metals from home-brewing ceramic pots have all caused problems with kombucha tea.

Does it boost immunity?

In this case, there could be good evidence that kombucha tea appears to aid the immune system because of the growth of good bacteria.  The beneficial bacteria help the body fight off viruses since the immune system is strengthened. 

Does it protect the liver?

Kombucha tea may have the ability to have protective effects for the liver according to a 2009 study.  This animal study showed that glucuronic acid found in the fermented tea reduced levels of toxins known to cause liver damage as the acid binds to toxins carrying them out of the body. 

Consuming kombucha responsibly

If kombucha tea sounds like a drink you want to give a try, go ahead but choosing home-brewed kombucha or unpasteurized kombucha is taking a risk.  There can be bad bacteria that can seep into the tea which is not worth the possibility of becoming sick. If homemade kombuchas are fermented in clay vessels or other containers that leach lead into the finished beverage, lead toxicity can be a danger. Also drinking too much kombucha could potentially lead to reactions like headache, nausea, GI upset or going into ketoacidosis (a medical emergency where there’s too much acid in your blood). 

Commercially available pasteurized kombucha is the better choice as it should be safe for healthy people.  To be on the safe side, the elderly, children, pregnant women and anyone with a compromised immune system or with a chronic disease (i.e., liver or kidney disease or HIV) should avoid it. 

As far as how much kombucha tea is safe to consume daily, the Centers for Disease Control recommends no more than 12 ounces of the drink a day.  At this time, there is not a lot of research identifying optimal quantities, or even benefits and risks of many probiotic foods.

Bottom line, the claims of kombucha tea as a magical elixir has not been proven by science.  If you’re healthy and like the taste, drink it in moderation realizing the health claims are not substantiated.