Beverages like kefir and kombucha could be called trends, but they also contribute to healthy guts. According to 2015 abstract by the National Institutes of Health, research to understand the gut microbiome in humans is in its early stages. The microbiome includes all the bacteria, viruses, fungi and other microscopic organisms that that live in the human body. All are important, but the gut contains 10 times as many microbial cells as the rest of the entire body.
Gut Bacteria and Health
The microbiome is necessary for proper nutrition, development, and immunity. When it goes awry, people can get illnesses like rheumatoid arthritis and diabetes. This is because the microbes change over time, affecting genetic activity and immune response. Not recognized until the 1990s, the microbiome helps digestion, protects against harmful bacteria and produces vitamins necessary for good health. Recent research shows that gut bacteria can affect mood and may be involved in depression.
Other studies show that highly processed foods contribute to inflammation and obesity, and recent data suggest that gut bacteria is necessary to produce neurotransmitters, such as GABA, serotonin, and dopamine, that regulate mood. Some scientists even call the gut the “second brain.” Eating enough fiber is critical, but nutritionists also recommend fermented foods like sauerkraut and pickles to keep gut bacteria healthy. Beverages like kombucha, a fermented tea, and kefir, fermented yogurt, also help.
What Kombucha Is and How It Works
It is a fermented effervescent drink made from black or green tea and sugar. Juice, extracts, spices and other kinds of flavors may be added to enhance the taste. Brewed from a living culture, or SCOBY, it has a pleasant taste that varies with the kinds of tea and flavorings used.
A SCOBY, or symbiotic culture of bacteria and yeast, resembles a mushroom. It is known as a “mother” and is similar to that found in vinegar. The SCOBY, in other words, is a living organism containing the bacteria and yeast that turn sweet tea into sparkling kombucha. This is the same process used to make kefir, ginger beer, and sourdough bread.
The retail production and the home-brewing niche have both surged in recent years. In the process, “contemporary” forms of kombucha with all kinds of health additives and flavors have become available. The lemon and ginger mixture, however, remains a favorite.
The History of Kombucha
No one is sure how kombucha got its start, but the Chinese have consumed it for at least 2,000 years. The first recorded history of its use dates to the Tsin Dynasty in China around 221 B.C., when it was called the “tea of immortality.” It was also popular in Japan, Russia, and Eastern Europe for hundreds of years.
Historians say the drink got its name from the Japanese in 415 A.D. As the story goes, a Korean doctor called Kombu gave the tea to the emperor for health reasons. In Russia, a medicinal tea called “tea kvass” was made from “Japanese mushrooms.” It was later consumed in Poland, Prussia, and Denmark, but its popularity fell during World War II. When the war ended, a German physician, Rudolph Skelnar, used kombucha to treat patients with high blood pressure, cancer, and diabetes.
In the 1970s, the tea entered the hippie culture and was touted as a health drink. It is now popular in the United States, where sales of fermented beverages increased by 37.4 percent in 2017.
The Beverage’s Alcohol Content
Technically, kombucha does contain alcohol. It is, after all, a fermented drink, and alcohol is one of the by-products of the fermentation process. How much alcohol it contains, however, depends on how long it is brewed. Homebrews usually have the highest levels, running up to 3 percent. A light beer, in comparison, has around 4 percent. Homebrewers often brew their tea two times to make it more effervescent and lower the amount of sugar in the final product. This also increases the amount of alcohol.
Another factor that affects alcohol levels is the kind of yeast used for brewing. Kombucha made from yeast that ferments at a lower temperature will have a low alcohol content. People who brew at home may heat their tea at high temperatures to get rid of harmful bacteria, and that also increases the amount of alcohol.
Commercial brewers, on the other hand, produce their kombucha in sterile environments that don’t require excessive heat. To qualify as a non-alcoholic beverage, their brew must be lower than 0.5 percent, the standard set by the U.S. Alcohol and Tobacco Tax and Trade Bureau.
In 2010, tests showed that many brands contained more than 0.5 percent alcohol, and some stores were carding customers to make sure they were 21 years or older. This led to Whole Foods temporarily pulling the bottles from their shelves, and federal agencies cracked down on the regulations. As a result, commercial brewers changed their formulas and put new testing in place. Some also started brewing tea that contained 3 to 5 percent alcohol and labeled them as alcoholic beverages.
Healthline.com makes the following recommendations for the consumption of kombucha:
- Pregnant or breastfeeding mothers should not drink the homebrew because its alcohol level is uncertain. Federal agencies recommend no alcohol during pregnancy or breastfeeding because it can pass through breastmilk.
- Unpasteurized tea may raise the risk of miscarriage. The Food and Drug Administration recommends that pregnant women stay away from all unpasteurized products to avoid harmful pathogens.
- It contains caffeine, and that could cause problems during pregnancy.
The 2019 Kombucha Industry Safety Fact Sheet says regular kombucha contains trace amounts of alcohol similar to that in unpasteurized fruit juice. It adds that the drink does not inebriate users and that the ethanol from the brewing process serves as a preservative. Certain kinds, such as kombucha beer, have higher alcohol levels and are sold as alcoholic beverages. They can only be purchased by adults aged 21 or older.
Kombucha Beer in the News
The controversy over the regulation of the tea and beer continues. With brands like Kombrewcha, Wild Tonic and Boochcraft selling beverages that contain anywhere from 3.2 to 9 percent alcohol, these ales have the same amount of alcohol as beers but are still below that of wine.
Large beer makers are also entering the market. Full Sail Brewing Company, for example, debuted its own line with hard tea and tea infused with coffee. Boston Beer, the maker of Samuel Adams, is coming out with its own concoction. It plans to sell the drinks in six states, including New York and California, before spreading to the rest of the country. The first flavors will be hibiscus-wild berry and blueberry-ginger. Makers tout the products as being low in calories and gluten-free.
Unlike some of the new products, it will contain probiotics and will not need to be refrigerated, but some brewers wonder if probiotics can survive in an alcoholic beverage. Nutritionists also wonder how many helpful probiotics are even in the non-alcoholic beverages and say more studies are needed. For one thing, the gut biome of every person is different. What’s good for one person may not be good for another. Others argue that the drink has other benefits that come from acetic, glucuronic, butyric and lactic acid.
Because health claims are more carefully regulated in alcoholic beverages, makers are less likely to make health claims than those with non-alcoholic versions. Indirect claims, such as implying fewer hangovers, are more probable.
In 2017, Medical News Week explored the ways fermented tea might be beneficial for health. Although many studies suggest benefits, much of the lab work has been done on animals. More research is needed to know exactly how helpful it will be and in which conditions it will be most useful, but here is an overview of some of the health claims:
Researchers think the ingredients in fermented tea have properties that regulate mood swings and lower symptoms of depression. If this is true, it may partially be due to the anti-inflammatory effects of the tea. A 2017 review of several studies strongly supported the claim that probiotics help to treat depression, but scientists still don’t know how effective they are.
Lower risk of cancer
Evidence also shows it might help to prevent the growth and survival of cancer cells. Because the research took place in test tubes, more study is needed.
Risk of infection
The fermentation process produces acetic acid, also a by-product of vinegar. Studies have shown it might help to kill microbes and fight off infection by killing the bacteria before the body absorbs them.
Studies suggest the ingredients in green tea may help with weight loss.
Diabetes II management
Probiotics lowered blood sugar levels in lab rats, but more studies are needed on humans.
Studies have shown that probiotics help to reduce cholesterol levels, but the research has only been done on rats. More research is needed.
Healthy liver function
Antioxidants in fermented tea have been shown to lower toxin levels in the liver.
Warnings and Precautions
Kombucha may be safe for most adults, but it can cause these side effects if it is contaminated: digestive problems, allergic reactions, jaundice, yeast infections, nausea, vomiting, headaches, neck pain or death. Especially when made at home, it can contain harmful bacteria or fungi.
People who have weakened immune systems, such as those with cancer or AIDS, are more likely to get sick than those who are healthy. Another risk comes from making the tea in a lead-glazed ceramic pot, which can cause lead poisoning. As mentioned above, pregnant or breastfeeding women or anyone who has a problem with alcohol should use caution.
Other precautions include the following:
Fermented tea contains varying amounts of sugar that can be hard to measure, especially in homebrew. Diabetics need to closely monitor blood sugar levels.
The caffeine in fermented tea can make diarrhea worse. Caffeine can also make IBS symptoms worse when used in excess.
Doctors recommend stopping consumption at least two weeks before surgery to avoid problems with blood sugar levels.
Weak immune system
There is a risk that bacteria or other contaminants in the tea could contribute to infections.
Because non-alcoholic kombucha is brewed in many ways and under varying conditions, it is impossible to make a blanket statement about its safety or benefits. Answers to questions about the safety and benefits of alcoholic versions are even less clear. Every person should consider the pros and cons of consumption and watch closely for positive or negative results. Kombucha is a healthy beverage when it is made correctly, but sometimes even that can be hard to establish.