Kombucha || Does it have the evidence to support the hype?
Kombucha is a delicious beverage that can be an extremely useful replacement for soft drink when transitioning to a more wholesome diet!
Kombucha is a a real buzz word and on trend in 2020, however has been reported throughout documentation from the time around 2200 BC; BC meaning ‘before christ’, not ‘before corona’, and originated from Northeast China.
Kombucha however, is a fermented tea beverage produced through aerobic fermentation of black or green tea (more commonly, black), and sugar by a combination of yeasts and bacteria that work in a symbiotic relationship culture, also known as a scoby. Through the fermentation process, sucrose is converted to ethanol, and then further fermented by bacteria to form acetaldehyde and acetic acid. The microbial and metabolite composition of kombucha with phenolic compounds and organic acids will vary depending on fermentation methods, such as location, temperature, and duration, among other things.
There are a number of health claims you have heard when you think of kombucha such as; Kombucha, may be protective against cancer, support gastrointestinal health and assist in the management of metabolic disorders. These are a few of the health claims I found to be associated with kombucha, when doing a recent assignment. The scientific research investigating these claims, interestingly was all but absent in the form of human clinical trails. A number of test tube (in vitro) and animal studies have been conducted assessing the effects of kombucha on metabolic parameters in diabetes, oxidative stress and cancer, however due to the nature of the research the scientific validity in the assumption that the research is translational into humans is largely unknown, The evidence at this stage shows promise, however is inconclusive and more research is needed to determine the health benefits of kombucha.
The microbiological, polyphenol and flavonoid content of kombucha is what makes the beverage attract so much attention. The polyphenol and flavonoid content of the tea increase with fermentation and suggests an increase in superoxide radicle scavenging ability (Dimidi et al., 2019). The specific strains of bacteria and fungi found in kombucha is extremely varied but typically includes acetic and lactic acid bacterias (Acetobacter, Gluconobacter, & Lactobacillus, Lactococcus), and yeasts (Saccharomyces, Zygosaccharomyces). Despite kombucha being a rich source bacteria and yeasts, there is still an absence of research assessing the effect of kombucha consumption on microbiota diversity within the gastrointestinal tract in either animals or humans.
The probiotic composition of kombucha is what majority of the health claims are based around. There is a broad body of evidence researching bacterial strains on human health, therefore the assumption is generally made linking the health benefits of probiotic supplementation with the consumption of kombucha.
There are a number of research articles with statistical significance in vitro and animal models, however zero clinical trials have been conducted therefore the effects in humans still remain largely unknown. In summary, further research is needed in human clinical trials to determine the physiological effects of kombucha consumption on gastrointestinal microbiological health.
SO…… What does this mean for you? Well, it means, kombucha contains a number of compounds such as probiotics, polyphenols and antioxidants and is a delicious beverage that are beneficial for human health. Should they be compared to a probiotic supplement? no, but they definitely can, and should be apart of a healthy diet. This information is not to say they should be avoided, by any means. It is simply highlighting the evidence surrounding the consumption of kombucha on gastrointestinal health. I drink kombucha on the reg because I love it!!
Reference:
Dimidi, E., Cox, S.R., Rossi, M. and Whelan, K., 2019. Fermented foods: definitions and characteristics, impact on the gut microbiota and effects on gastrointestinal health and disease. Nutrients, 11(8), p.1806.