Kombucha: Wonder Drink or Hyped Up Tea?

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Kombucha: Wonder Drink or Hyped Up Tea?
By Laura Bartee, RD, LD
B
eer, yogurt, pickles,
kefir, sauerkraut,
miso, kombucha.
Other than foods that
might be found at a
summer picnic, these are
also foods that have
Laura Bartee, RD, LD
been fermented and
have purported various health benefits,
particularly on gut health (well, other than
beer’s uncanny ability to create a belly).
Kombucha is one of the lesser known
fermented foods, but it has a large following
of supporters and believers who report
significant anecdotal and testimonial
benefits to health. Kombucha is fermented
black or green tea that is created by
combining tea, sugar and a kombucha
starter. Kombucha starters are made from a
combination of yeasts and bacteria that
ferment the sugar in the tea and produce
ethanol and different acids: lactic, acetic,
gluconic and glucuronic (1). The tea offers
the bacteria and yeast, as well as other
byproducts of fermentation such as high
amounts of B vitamins, sometimes vitamin C,
polyphenols and small amounts of alcohol
(2). It is speculated the original health
benefits of the tea remain intact in the drink,
however this has not been proven in
scientific research at this time (1).
For years people have speculated and
shared the believed health benefits of this
acidic, carbonated mildly sweet tea
including immune boosting properties, a
possible cure for HIV, cancer fighting
nutrients and improvements in gut health
and nutrient metabolism. At this time,
there have been studies of these reported
benefits in animal models, most with
inconclusive evidence (4). Little to no
research has been done in human
populations – and the numerous benefits
reported by followers have never been
proven in the scientific community.
Unfortunately, there have been reported
cases of toxicities, illness and even a few
deaths from kombucha ingestion (3).
While tea has been proven in numerous
experimental studies to provide significant
benefits to health, the fermentation
process and byproduct of the tea is not
well understood and not well researched
at this time (1).
Kombucha is now sold commercially, in
different formulations and flavors. Some
kombucha is raw and organic, containing
the original bacteria, yeast and ethanol
produced. Several years ago, a specific
brand of commercial kombucha was pulled
from shelves because the alcohol content
of the beverage was much higher than was
reported on labels. This variation is now
sold only to buyers 21 years of age and
older. For those who want the reported
benefits without the risk of ingesting the
original bacteria and yeast, pasteurized
kombucha is sold (1,5). While tea is
naturally calorie free, commercial varieties
of kombucha contain sugar and range from
approximately 60 to 150 calories a bottle.
Home brewed kombucha is very popular
and unfortunately can lead to unwanted
consequences if not done correctly.
Kombucha must always be fermented in a
glass container, because chemicals in the
container can be leeched into the drink
due to its high acidity, creating dangerous
risks for those who ingest the tea (3). Like
many other fermented products, the inside
environment is protective of detrimental
bacteria infiltration (1). However, mold and
other harmful bacteria can grow on the
top of the kombucha liquid and can be
unsafe to consume (2). Kombucha starters
are often passed from household to
household and can become contaminated
as well, so encourage careful practices
when home brewing (1). Cases of
transaminitis, hepatotoxicity and lactic
acidosis have been reported in the
medical community, though cause for
these cases is unknown (3).
The health benefits of kombucha are
unknown at this time and not proven in
scientific research. Frequent consumption of
kombucha has been proven to be medically
detrimental in some individuals (3), and will
be a contributor to daily caloric and sugar
intake. For those individuals who decide to
drink kombucha, encourage safe practices
with home brewed variations and encourage
intake of commercial varieties which are
subjected to standards for cleanliness (5).
Further research in human models must be
done before kombucha can be proven to be
significantly beneficial to health. For those
who are skeptical, encourage intake of
unsweetened teas to receive similar nutrient
profiles and a similar, yet less acidic taste.
Laura is a Clinical Dietitian at Baylor All Saints
Medical Center in Fort Worth, Texas, where her
primary area of practice is conventional weight
management and post-bariatric surgery. In her
personal life she enjoys reading, running road
races and considers herself a chip-a-holic.
References:
1. Dufresne C, Farnworth E. Tea,
Kombucha, and health: a review. Food
Res Int. 2000;(33):409-421.
2.Sedin F. Ancient kombucha: a new way
to rejuvenate the body?. Alive: Canada’s
Natural Health & Wellness Magazine [serial
online]. March 2010;(329):40.
3.Kole AS, Jones H, Christensen R, Gladstein
J. A Case of Kombucha Tea Toxicity. J
Intensive Care Med. 2009;(24):205.
4.Kallel L, Desseaux V, Hamdi M, Stocker P,
Ajandouz E. Insights into fermentation
biochemistry of Kombucha teas and the
potential impacts of Kombucha drinking
on starch digestion. Food Res Int.
November 2012;(491):226-232.
5.Nummer, B. Kombucha Brewing Under
the Food and Drug Administration
Model Food Code: Risk Analysis and
Processing Guidance. Journal of
Environmental Health. November
2013;(4):8-11.
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Weight Management Matters
Summer 2014