Kombucha is a fizzy, fermented beverage typically crafted from green or black tea. Despite sometimes being called kombucha mushroom tea, it contains no fungi. The “mushroom” is actually a symbiotic colony of bacteria and yeast, known as a SCOBY. When introduced to sweet tea and allowed to ferment, it generates beneficial bacteria and B vitamins. This has led to its classification as a functional beverage, defined as any nonalcoholic drink with added ingredients intended to promote health benefits. While relatively new to the United States, kombucha has a history spanning over 2,000 years. It originated in China before spreading to Japan and Russia, gaining popularity in Europe during the early 20th century. U.S. sales are increasing due to its reputation as a health and energy drink. Numerous claims suggest kombucha can alleviate or prevent various health issues, including obesity, cardiovascular disease, cancer, and diabetes. Scientists are actively investigating evidence to support these assertions and explain why certain components of the drink might be beneficial.
In its simplest form, kombucha is described as having a mildly sweet and vinegary taste or tanginess. It is often enhanced with flavors like fruit, honey, or sugar. The fermentation process imparts a refreshing fizz to the drink. The basic ingredients for kombucha are yeast, sugar, and tea. This mixture is set aside for a week or longer. During this period, bacteria and acids develop in the beverage, along with a small amount of alcohol, typically below 0.5%. This fermentation process is similar to how cabbage is preserved as sauerkraut or kimchi, or how milk is transformed into yogurt.
To initiate the chemical process of fermentation, which gives kombucha its flavor and nutritional properties, bacteria and yeast are essential. This mutually beneficial, or symbiotic, relationship occurs when yeast breaks down the sugar added to the tea, which then nourishes the bacteria that produce acid in the form of vinegar. When the SCOBY is added to sweet tea, it forms a film or spongy, jelly-like substance on the surface. This is why it is often referred to as a mushroom, although it is not a fungus. You might also hear it called the kombucha mother.
To begin your first batch of homemade kombucha, you need a SCOBY. You can preserve the SCOBY and reuse it for future batches. A basic kombucha recipe includes: ¼ cup of loose green or black tea in mesh bags or 4-8 tea bags, 1 gallon of filtered water, 1 cup of cane sugar, 1-2 cups of kombucha starter liquid (often included with your SCOBY or available for purchase), and 1 SCOBY. Add black or green tea to boiling water, stir in the sugar, and remove the tea leaves or bags after about 10 minutes. Allow the tea to cool to room temperature before transferring it to a large glass or stainless steel container and adding the SCOBY. You may also incorporate a little vinegar and other flavorings, such as fruit puree, spices, or herbs. Cover the jar opening with cheesecloth or a coffee filter, securing it with a rubber band to prevent contamination. Let it ferment at room temperature for 7-10 days. Reserve at least 1-2 cups to use as starter liquid for your next batch, then refrigerate the remainder to halt fermentation. If fermentation continues beyond 10 days, your kombucha may turn into vinegar. Note: To avoid contamination from mold or harmful bacteria that could cause illness, always wash your hands thoroughly and sterilize any container used for brewing or storing kombucha.
Since kombucha is fermented, it contains a low level of alcohol, typically below 0.5%. When made with green, black, or other caffeinated teas, it will contain caffeine, but the levels are very low—less than 15 milligrams per cup.
For centuries, kombucha has been consumed for its health benefits. The fermented tea contains vitamins, trace minerals, and antioxidants—compounds that can protect your cells from damage. It is free of fat and cholesterol and low in sodium. It also includes probiotics, which are beneficial bacteria that can enhance gut health. However, there is limited scientific research to substantiate the many health claims made by manufacturers and enthusiastic kombucha fans.
An 8-ounce serving of unflavored kombucha contains approximately 30 calories, 2-3 grams of sugar, and a small amount of caffeine. Adding flavorings or fruit to kombucha may increase its nutritional value, calories, and sugar content.
Drinking kombucha may offer a variety of health benefits, from aiding digestion to eliminating toxins from the body and boosting energy levels. It is also said to support the immune system, assist with weight loss, ward off high blood pressure and heart disease, and prevent cancer. However, there is insufficient evidence to back these claims.
Fermented products in general are beneficial for the microbiome and gut health. Fermentation produces probiotics, which can help with constipation, diarrhea, and irritable bowel syndrome (IBS). Yet, there is not enough research to demonstrate how these probiotics function. Experts recommend obtaining probiotics from a plant-based diet until more is known.
Because kombucha is made from either black or green tea, you benefit from the natural antioxidant properties of tea. Antioxidants help protect cells against damage. The fermentation process may enhance these immune-boosting compounds. Gut health has been linked to the immune system, so probiotics that improve gut health may also help strengthen the immune system.
A recent study found that drinking kombucha may help lower triglyceride levels—in worms. The study observed that drinking kombucha might create a metabolic change in the stomach that mimics fasting. Researchers also noted a reduction in fat accumulation, specifically triglycerides—the fat stored in the body when you consume more calories than you burn. More research is necessary to determine if kombucha could have the same effect in humans.
Research indicates a relationship between gut health and heart health. Other studies in animals show that the drink lowers cholesterol. However, research has not demonstrated that it has the same effects in people.
In a recent study, kombucha helped lower blood sugar levels in people with diabetes. On average, their fasting glucose levels decreased from high to healthy levels. Scientists do not fully understand why kombucha, which contains sugar, may be effective in reducing blood sugar levels, and more research is needed.
The enzymes and acids produced during kombucha’s fermentation process may help remove toxins from the liver.
When kombucha is made from black tea or green tea, you also gain the benefits of these teas. This includes bioactive antioxidant compounds like polyphenols, which act as antioxidants. The fermentation process has been shown to increase antioxidant levels.
Making kombucha involves allowing bacteria to grow in a liquid you intend to drink. While these bacteria are considered healthy, improper preparation can lead to the growth of harmful bacteria or mold. If brewing at home, experts advise using glass, stainless steel, or plastic containers. Maintain strict sanitation, including equipment and hands. Since the mid-1990s, several cases of illness and at least one death have been reported in individuals who consumed kombucha. Ailments included liver problems, lactic acidosis (a buildup of lactic acid in the body), allergic reactions, and nausea. Consequently, the CDC recommends drinking only 4 ounces of kombucha daily. Overconsumption can result in side effects such as headache, nausea, and upset stomach.
When properly prepared and consumed in moderation, kombucha is generally considered safe. However, if you are pregnant, experts advise against drinking homemade or store-bought kombucha. There are two primary reasons: alcohol and caffeine. Even low levels of alcohol in kombucha pose a risk to pregnant women. Similarly, the caffeine levels in kombucha may not be ideal for expectant mothers. There is also the potential for bacterial contamination in kombucha, especially if made at home.
Kombucha is not recommended for young children. Older children may enjoy it, but due to its caffeine and small alcohol content, experts suggest limiting your child’s daily kombucha consumption. If you are pregnant or have a weakened immune system due to illness or treatment, you should avoid drinking kombucha. Otherwise, in moderation, you can drink kombucha daily.
Today, commercially produced kombucha drinks are available in most grocery and convenience stores and can be ordered online. If you wish to make kombucha at home, kombucha kits, including starter liquid and SCOBY, can be purchased online or at specialty health food stores.
Store-bought kombucha may last in an airtight container in the refrigerator for up to a week after opening. After a week, your kombucha may lose its fizz and nutritional value. Kombucha that has gone bad will smell and taste vinegary and may appear cloudy or slimy—it should be discarded.
Kombucha is an ancient fermented tea that may offer many health benefits, such as improving digestion, boosting the immune system, lowering cholesterol levels, and supporting cardiovascular health. Today, kombucha is widely available in stores, and starter kits can be purchased for home brewing. It is crucial to follow safety guidelines when making kombucha at home to avoid contamination that could lead to potential food poisoning.
Drinking kombucha may provide a variety of health benefits, from aiding digestion to eliminating toxins from the body and boosting energy levels. It is also said to help the immune system, assist with weight loss, ward off high blood pressure and heart disease, and prevent cancer. However, there is not a lot of evidence to support these claims. Yes, kombucha is made with a symbiotic colony of bacteria and yeasts (SCOBY) that includes lactic-acid bacteria, which can function as a probiotic. You can drink kombucha as a substitute for soft drinks. You consume kombucha for its potential health benefits, including relieving stomach upset, boosting your immune system, or helping to lower high cholesterol levels.
