Shaun Ward MSc ANutr
Kombucha in its original form is a culture of acetic acid bacteria and different yeasts that form a type of fungus.
Kombucha became a popularized tea – Kombucha Tea - that is now one of many traditional fermented foods, and is referred to as a “functional beverage” for its apparent health benefits.
The exact origins of kombucha as a drink are not known, although speculated to originate in Northeastern China, before becoming a popularized drink in Russia and eastern Europe.
Nowadays, Kombucha is homebrewed in most modern countries and sold commercially by various companies as a health drink.
Curative effects for a number of conditions been attributed to Kombucha tea, however these rely mainly on subjective observations and testimonials. There is a scarce amount of research analyzing the effects of Kombucha in scientific and experimental studies.
The Potential Benefits of Kombucha
Below is a list of all the health benefits we've confirmed that are backed by science:
It's A Potential Antioxidant
Free radicals formed in the body can cause oxidative stress and cell damage when the production of free radicals overwhelms the body’s antioxidant defenses. Due to this, it is becoming increasingly popular to include products high in anti-oxidants within one’s daily eating routines.
The majority of Kombucha Tea’s health benefits are attributed to its antioxidant activity, which may help to cure many chronic illnesses caused by oxidative stress.
Kombucha Tea’s anti-oxidant ability is likely due to its nutritional content of vitamins E, C, beta-carotene, and phenolic acid.
In preclinical trials, the high content of phenolic compounds in Kombucha Tea is also seen to scavenge hydroxyl and superoxide radicals – which would otherwise damage DNA, protein, and lipids .
At least in animals, Kombucha Tea decreases oxidative stress and its consequential suppression of the immune system .
This had led to reduced cell damage, inflammatory disease onset, depression of immunity, and tumor growth in animals .
This extent to which this translates to human practices is arguable, and future research is needed for clarification.
It May Help Gastric Illnesses
Particular attention to Kombucha Tea is due to its connection with influencing the digestive system.
Indeed, studies have mentioned that it may intestinal activities and certain gastric functions.
Kombucha Tea may be particularly involved with physiological actions such as the contractions of the stomach and intestines .
In mice, much research has shown Kombucha Tea may improve gut barrier integrity – preventing mucosal injury – and inhibit the progression of stomach ulcers. In fact, Kombucha Tea is more effective at this compared to black tea .
It seems Kombucha Tea has a specialized ability to protect against gastric illnesses by guarding the intestinal barrier (mucosal barrier) via reduced inflammation and gastric acid secretion - which typically damages the mucous membrane and causes stomach ulceration.
It May Reduce Cholesterol Levels
The high level of glucuronic acid may also decrease blood cholesterol levels, although this has only been seen in animal studies; ~50% lower total cholesterol, ~75% decline in LDL-cholesterol, and ~20% increase in HDL-cholesterol 
It is speculated that Kombucha Tea could potentially reduce cholesterol levels by inhibiting the activity of the cholesterol synthesis enzyme, HMG, or through a mechanism that increases the excretion of cholesterol.
This stems from reports that glucuronic acid may neutralize cholesterol deposits and aid their excretion via liver and kidneys.
This has been documented to help reduce atherosclerosis through the regeneration of the cellular wall .
It May Aid Detoxification Processes In The Elderly
Kombucha Tea contains a substance known as glucuronic acid, known to aid detoxification processes in the body.
It is worth noting that natural processes for detoxification do not need nutritional help in the vast majority of people, but there may be certain susceptible individuals who have a reduced capability to transform and excrete foreign substances, such as the elderly.
Glucuronic acid forms with toxic metabolites and exogenous chemicals that are not expected to be within the body called xenobiotics; pharmaceuticals, environmental pollutants, toxins.
Glucuronic acid changes the xenobiotic structure to increase their solubility and allow for easier release from tissues and then excretion from the body.
It May Prevent Against Infectious Diseases
The fermentation process for Kombucha Tea can also lead to a production of natural antimicrobials – such as acetic acid - that may benefit against infectious diseases.
It is only speculation, but the bacteria and yeasts present in kombucha may form a “symbiosis” that could potentially inhibit the growth of harmful contaminating bacteria .
Many studies have also stated that the great acidity of Kombucha Tea can exert antibacterial activity against some common bacteria such as Salmonella, Staphylococcus Aureus, and Bacillus Cereus.
The acidic environment that Kombucha Tea creates may lead to ideal activities of antimicrobials such as acetic acid, as they are then able to freely pass through the cell walls and have an effect.
The antimicrobial effects on any pathogenic bacteria may include membrane disruption, inhibited metabolic reactions, or stress on the intracellular homeostasis .
Safety and Side Effects
The Food and Drug Administration states Kombucha is safe for most individuals to consume up to 4 ounces per day. Comparatively, The Centers for Disease Control recommends that 4 ounces of Kombucha can be safely consumed one to three times a day.
Based on this, 4-12 ounces of Kombucha per day is a safe recommendation.
However, various side effects from Kombucha have been noted. These include symptoms of allergic reactions, jaundice, nausea, vomiting, head and neck pain.
However, most side effects are reported to be due to poor handling of the product during home cooking and fermentation.
If individuals are thinking of making their own Kombucha at home, be careful that the fermentation process does not lead to contamination as this can attract harmful bacteria and mold.
Those new to drinking Kombucha can experience temporary discomfort due to slight changes in their gut microbiome adjustments. Due to this, individuals are recommended to start with very low amounts and increase accordingly to minimize negative symptoms.
Consuming Kombucha isn’t advised for those with immune system problems, pregnant or breastfeeding women, or those under the age of 18.
Please be aware that kombucha may contain up to 3% alcohol, with homepage versions often having a higher alcohol percentage.
How Much Kombucha Should You Drink?
It is recommended to start with 2 ounces of store-bought Kombucha per day.
After a month, this can be increased to 4 ounces.
If no side effects are noted, continually up the amount by 2 ounces each month, but do not go beyond the 12 ounces per day limit set by The Centers For Disease Control.
If any side effects are apparent, dramatically reduce the amount of Kombucha being consumed or completely remove it from the diet.
Kombucha is a culture of acetic acid bacteria and different yeasts that have now become part of a popularized fermented tea – Kombucha Tea.
Kombucha’s micronutrient and phytonutrient content may have various health benefits such as having antioxidant and antibacterial properties.
It could also potentially help improve the immune system and reduce cholesterol levels.
However, Kombucha has only been studied in animals and its effects in humans are not well-known.
Kombucha is generally safe to consume under 12 ounces per day, with minimal side effects noticed under 4 ounces per day, unless there has been product contamination.
It is recommended to start with 2 ounces of shop-bought Kombucha per day and increase the amount by 2 ounces per month until positive effects are noted. If side effects occur, dramatically reduce the dosage or discontinue use.