Saturday, 10 December 2016

Kombucha


Kombucha is a drink I have recently encountered. It tastes good. Some acolytes have told me it does miraculous things; that it is beneficial for health; it is a miracle drink.

Is this true?  What can I find out?

I will start with basics.

What is Kombucha?

Kombucha is a fermented lightly effervescent sweet tea made from tea, sugar and a scoby.

What is its history?

Kombucha originated in Manchuria and was imported into Japan in about 400 AD. The Japanese developed it and it is now considered Japanese in origin.
Kombucha is made by adding a scoby to sweet tea. Fermentation occurs creating a minimal amount of alcohol, organic acids, enzymes, and bacteria.
The scoby is a flat mushroom-like culture containing live yeast and bacteria which floats on top of the liquid.
The second stage of fermentation. The scoby is removed from the kombucha. The kombucha is bottled and carbonation produces bubbles in the kombucha.

Composition

Kombucha contains live yeasts and bacteria, various organic acids, ethanol, sugars, anti-oxidants, enzymes.
The live bacteria act as a probiotic.
The organic acids are acetic, glucuronic, gluconic, lactic, usnic, citric, malic, tartaric, malonic, oxalic, succinic, pyruvic.
The sugars are sucrose, glucose and fructose.
Contains small amounts of Vit B1, B2, B6, B12 and C, amino acids, amines, purines, pigments, lipids, proteins, and some hydrolytic enzymes.

Nutritional Information

A cup of kombucha tea contains:
0 fat
0 protein
0 fiber
3gm carbohydrate 1% of RDI
Thiamin 4 % of RDI
Riboflavin 4 % of RDI
Niacin 4 % of RDI
Vitamin B-6 4 % of RDI
Folate 6 % of RDI
Vitamin B-12 4 % of RDI

The main nutritional value is in the live bacteria (act as probiotics).

Is it the miracle drink?

A lot of the web sites either praise kombucha or criticize it.  I will look at both.

The arguments for drinking kombucha

People have used kombucha to prevent or treat HIV; cancer; diabetes; heart disease; lung disease; urinary tract infections; stimulate the immune system; improve hair, skin and nails; increase libido; detoxify the body; reduce inflammation; aid joints; promote liver function; cure hemorrhoids; regulate unhealthy appetites leading to weight  loss;  improve immune system.

The main argument for kombucha says digestion is improved. Kombucha contains probiotics, anti-oxidatives, organic acids, and enzymes which aid digestion. The organic acids change the acid-alkaline balance in the digestive tract which enables nutrient absorption and waste removal. Kombucha contains probiotics (live bacteria) which can result in good bacteria crowding out bad pathogenic bacteria.

The arguments against drinking kombucha

Some adverse health effects may be due to the acidity of the tea, which can cause acidosis.
Usnic acid is toxic to the liver.
Bacterial or fungal contamination.
Unpasteurized kombucha can ferment in the bottle, unless it is refrigerated, bringing its alcohol content to the level of some beers. Pasteurizing the beverage kills all pathogenic bacteria, beneficial bacteria and fixes the alcohol level.

Bottom Line

It contains live bacteria. There is the benefit of increasing the variety of bacteria in your gut.  There is the risk, especially if homemade, the bacteria may be the wrong ones for you. 

Kombucha contains alcohol and sugar in small amounts. For most people the amount is maneable. The alcohol can protect against pathogenic bacteria.

The arguments saying that kombucha aids digestion are convincing. 

The arguments about the benefits of certain vitamins and minerals are not convincing because the amounts are so small.
The arguments saying kombucha is toxic to the liver and kidney are unconvincing.  In fact alternate arguments about the ability of kombucha to detoxify the body to eliminate toxins are more convincing.  There is evidence that kombucha is hepatoprotective because it contains anti-oxidants.

The list of diseases kombucha is meant to help manage is lacking scientific evidence.

It all comes down to bacteria. If you believe that the type and number of bacteria in your gut is important then kombucha will probably increase the diversity of bacteria in your gut. Depends on the bacteria in the kombucha and in your gut. The bacteria in the kombucha will depend on how it was made. The type and number of bacteria in your gut will vary constantly. Should be consumed in small amounts. A little bit may be good for you but that doesn’t mean a lot will be better.  Definitely a product where if a little is good then a lot is better does not apply. It is not a miracle drink. It doesn’t do miraculous things.