Kimchi, a cornerstone of Korean cuisine, has garnered global attention for its unique flavor and potential health benefits. This traditional dish, made with salted, fermented vegetables, primarily cabbage, offers a complex blend of nutrients, probiotics, and active compounds. While celebrated as a health-boosting food, understanding both the advantages and potential risks associated with kimchi consumption is essential.
What is Kimchi?
Kimchi is a traditional Korean dish made with salted, fermented vegetables. It can contain a variety of ingredients but most often includes cabbage and seasonings such as sugar, salt, onions, garlic, ginger, and chili peppers. It is a traditional Korean dish that consists of fermented, salted vegetables. Kimchi typically contains cabbage and seasonings like sugar, salt, onions, garlic, ginger, and chili peppers. It may also boast other vegetables, including radish, celery, carrot, cucumber, eggplant, spinach, scallions, beets, and bamboo shoots.
Historically, it hasn’t always been possible to grow fresh vegetables throughout the year. Before advances in agriculture and technology, it was difficult to store food for long periods of time without spoilage. Therefore, people have developed food preservation methods, such as pickling and fermentation - a process that uses enzymes to create chemical changes in food that can improve the shelf life of some foods and beverages. Traditionally, during the fermentation process of kimchi - which can take up to 1 month - people place kimchi in special jars that they partially or totally store underground.
Nutritional Profile of Kimchi
Kimchi is packed with nutrients while being low in calories. The nutritional content of kimchi can vary due to it having more than 200 different variations. Since kimchi varies widely in ingredients, its exact nutritional profile differs between batches and brands. On its own, Chinese cabbage - one of the main ingredients in kimchi - boasts vitamins A and C, at least 10 different minerals, and over 34 amino acids (3). All the same, a 1-cup (150-gram) serving contains approximately (4, 5):
- Calories: 23
- Carbs: 4 grams
- Protein: 2 grams
- Fat: less than 1 gram
- Fiber: 2 grams
- Sugar: 2 grams
- Sodium: 747 mg
- Vitamin B6: 19% of the Daily Value (DV)
- Vitamin C: 22% of the DV
- Vitamin K: 55% of the DV
- Folate: 20% of the DV
- Iron: 21% of the DV
- Niacin: 10% of the DV
- Riboflavin: 24% of the DV
Many green vegetables are good sources of nutrients like vitamin K and riboflavin. Because kimchi often comprises several green veggies, such as cabbage, celery, and spinach, it’s typically a great source of these nutrients. Vitamin K plays an important role in many bodily functions, including bone metabolism and blood clotting, while riboflavin helps regulate energy production, cellular growth, and metabolism (6, 7). What’s more, the fermentation process may develop additional nutrients that are more easily absorbed by your body (8, 9, 10). The abundance of minerals, vitamins, and antioxidants present in kimchi can provide important health benefits.
Read also: Kimchi on Keto Diet
The Fermentation Process and Probiotics
The lacto-fermentation process that kimchi undergoes makes it particularly unique. The method of producing fermented foods such as kimchi involves a lacto-fermentation process that uses the Lactobacilli bacteria to break down sugar and starches into lactic acid. Fermented foods not only have an extended shelf life but also an enhanced taste and aroma (11). Fermentation occurs when a starch or sugar is converted into an alcohol or acid by organisms like yeast, mold, or bacteria. Lacto-fermentation uses the bacterium Lactobacillus to break sugars down into lactic acid, which gives kimchi its characteristic sourness. These “good bacteria” are also present in yogurt, and people often refer to them as probiotics. Eating fermented foods containing probiotics can help maintain healthy gut flora and reduce the negative symptoms of digestion-related conditions.
When taken as a supplement, this bacterium may offer several benefits, including treating conditions like hay fever and certain types of diarrhea (12, 13, 14, 15). Fermentation also creates an environment that allows other friendly bacteria to thrive and multiply. These include probiotics, which are live microorganisms that offer health benefits when consumed in large amounts (16, 17). In fact, they’re linked to the prevention and treatment of several conditions, including:
- certain types of cancer (18, 19, 20)
- the common cold (21)
- constipation (22)
- gastrointestinal health (11, 23, 24, 25, 26)
- heart health (27)
- mental health (28)
- skin conditions (29, 30, 31, 32)
Keep in mind that many of these findings are related to high-dose probiotic supplements and not the amounts found in a typical serving of kimchi. The probiotics in kimchi are believed to be responsible for many of its benefits. Nonetheless, more research on the specific effects of probiotics from fermented foods is needed (9, 33, 34). Thanks to its probiotic contents, kimchi is a healthy, gut-boosting side dish that can, if eaten regularly, even help consumers lose excess weight.
Potential Health Benefits of Kimchi
Kimchi has been shown to fight inflammation, prevent colon cancer, reduce cholesterol and blood glucose, strengthen the immune system and prevent atherosclerosis, the buildup of plaque in the arteries. The abundance of minerals, vitamins, and antioxidants present in kimchi can provide important health benefits. For example, some evidence suggests that kimchi may help promote good health and may help prevent or control certain conditions.
Improved Digestion
The fiber and probiotics in kimchi can help you maintain a healthy digestive system. The probiotics in fermented food can help reduce the negative symptoms of many gastrointestinal disorders, such as irritable bowel syndrome and colon inflammation. The method of producing fermented foods such as kimchi involves a lacto-fermentation process that uses the Lactobacilli bacteria to break down sugar and starches into lactic acid. Eating fermented foods containing probiotics can help maintain healthy gut flora and reduce the negative symptoms of digestion-related conditions. Consumption of regular kimchi, kimchi with added Lactobacillus plantarum, and functional kimchi with Lactobacillus plantarum and mistletoe extract were linked to improvements in symptoms of irritable bowel syndrome (IBS), such as abdominal pain, bloating, and incomplete evacuation.
Read also: Spicy Keto with Kimchi
Immune System Support
In addition to reducing inflammation, some research suggests that eating fermented foods such as kimchi can also help remodel the gut microbiome and alter and strengthen the immune system. Early research suggests kimchi may strengthen your immune system. The bacteria in kimchi are linked to improved immune function and lower levels of inflammation triggered by diseases. The vitamin C found in kimchi can also help boost your immune health.
This is consistent with a 2014 mouse study that indicates that consuming kimchi can lower levels of the inflammatory marker tumor necrosis factor-alpha, which is typically present in higher levels in the body during infections. A 2019 test-tube study investigating bacteria in kimchi also notes that it possesses immune-enhancing effects. A specific strain of Lactobacillus found in kimchi may boost your immune system, though further research is necessary. In a study in mice, those injected with Lactobacillus plantarum - a specific strain that’s common in kimchi and other fermented foods - had lower levels of the inflammatory marker tumor necrosis factor alpha (TNF alpha) than the control group (35). Because TNF alpha levels are often elevated during infection and disease, a decrease indicates that the immune system is working efficiently (36, 37). A test-tube study that isolated Lactobacillus plantarum from kimchi likewise demonstrated that this bacterium has immune-enhancing effects (38).
Anti-Inflammatory Properties
Probiotics and active compounds in kimchi and other fermented foods may help fight inflammation (39, 40). HDMPPA, an active compound in kimchi, may play a large role in reducing inflammation. Chronic inflammation is not only associated with numerous illnesses but also accelerates the aging process.
For example, a mouse study revealed that HDMPPA, one of the principal compounds in kimchi, improved blood vessel health by suppressing inflammation (41). In another mouse study, a kimchi extract administered at 91 mg per pound of body weight (200 mg per kg) daily for 2 weeks lowered levels of inflammation-related enzymes (42). Meanwhile, a test-tube study confirmed that HDMPPA displays anti-inflammatory properties by blocking and suppressing the release of inflammatory compounds (43).
Heart Health
Inflammation is one contributing factor to metabolic syndrome, which refers to a cluster of conditions that occur together to increase the risk of heart disease, stroke, and type 2 diabetes. People with risk factors such as high cholesterol and chronic inflammation are much more likely to develop heart disease. Probiotics may improve heart health by reducing cholesterol and inflammation. The fiber, antioxidants, and nutrients in kimchi can also help lower blood sugar and cholesterol levels, which can boost heart health.
Read also: Kimchi and the Carnivore Diet
Kimchi may also help lower cholesterol. Kimchi may lower your risk of heart disease by reducing inflammation, suppressing fat growth, and decreasing cholesterol levels. Research indicates that kimchi may reduce your risk of heart disease (51). This may be due to its anti-inflammatory properties, as recent evidence suggests that inflammation may be an underlying cause of heart disease (52, 53, 54). In one 2018 study, researchers fed mice a high cholesterol diet, with some mice receiving kimchi extract. The mice consuming the kimchi had lower fat levels in the liver and circulating blood than those only consuming the high cholesterol diet. In an 8-week study in mice fed a high cholesterol diet, fat levels in the blood and liver were lower in those given kimchi extract than in people in the control group. In addition, the kimchi extract appeared to suppress fat growth (55). Meanwhile, a weeklong study including 100 people found that eating 0.5-7.5 ounces (15-210 grams) of kimchi daily significantly decreased blood sugar, total cholesterol, and LDL (bad) cholesterol levels - all of which are risk factors for heart disease (56).
Weight Loss
Kimchi is not only low in calories but may also help with weight loss. With only 23 calories per cup, kimchi is a low-calorie food. It also contains fiber, which can help you feel full and ward off hunger. One small study found that eating kimchi as part of a monthlong diet helped people with overweight or obesity shed weight and body fat. Eating kimchi may also prevent weight gain. Research shows that men who had one to three servings of kimchi daily were 10% less likely to become obese than those who didn’t eat kimchi.
Similarly, an 8-week mouse study indicates that kimchi may exhibit anti-obesity activity. A 4-week study in 22 people with excess weight found that eating fresh or fermented kimchi helped reduce body weight, body mass index (BMI), and body fat. Additionally, the fermented variety decreased blood sugar levels (50). Keep in mind that those who ate fermented kimchi displayed significantly greater improvements in blood pressure and body fat percentage than those who ate the fresh dish (50). It’s unclear which properties of kimchi are responsible for its weight loss effects - though its low calorie count, high fiber content, and probiotics could all play a role. A 12-week randomized clinical trial in 114 adults with obesity suggests that Lactobacillus sakei derived from kimchi might help reduce body fat mass and waist circumference.
Anti-Aging Properties
In a test-tube study, human cells treated with kimchi demonstrated increased viability, which measures overall cell health, as well as showed an extended life span regardless of their age (44). Still, overall research is lacking. Many more studies are needed before kimchi can be recommended as an anti-aging treatment.
Potential to Prevent Yeast Infections
Test-tube and animal studies suggest that certain strains of Lactobacillus fight Candida. One test-tube study even found that multiple strains isolated from kimchi displayed antimicrobial activity against this fungus (46, 47, 48). Probiotic-rich foods like kimchi may help prevent yeast infections, though research is in the early stages.
Risks and Considerations
Although kimchi may exhibit many potential health benefits, it still contains live bacteria. Kimchi can provide some potential health benefits, but the fermentation process it undergoes also means that it may come with some risks. Kimchi has very few risks. Nonetheless, this dish has been tied to outbreaks of food poisoning, so people with compromised immune systems may want to use extra caution. The authors also mentioned that despite the various benefits of kimchi consumption, there were concerns about the high salt content of kimchi.
Food Safety
The bacteria that people use to ferment kimchi are safe to consume. However, people must prepare and store kimchi correctly, or there may be a risk of pathogenic bacteria growth during fermentation and storage. Foodborne pathogens are not typically present in fermented foods. This is because lactic acid typically forms during fermentation, which can help control any harmful pathogens that may be present. However, like most foods, kimchi is still vulnerable to these harmful microorganisms.
Recently, this dish has been linked to E. coli and norovirus outbreaks (57, 58). In the past 10 years, researchers have linked kimchi to outbreaks of both Escherichia coli and norovirus. Even though fermented foods don’t typically carry foodborne pathogens, kimchi’s ingredients and the adaptability of pathogens mean that it’s still vulnerable to them. People can minimize the risk of food poisoning by buying kimchi from a reliable retailer and ensuring that they store it correctly. As such, people with compromised immune systems may want to practice caution with kimchi.
High Sodium Content
Another consideration is the high sodium content in kimchi. The nutritional value of kimchi can vary. However, the serving comes with 747 milligrams of sodium. Kimchi is high in sodium, with about 500 milligrams per cup. That’s more than 20% of all the sodium that you’re supposed to get in a day. People at risk of high blood pressure might have concerns about the high salt content of this food. Excessive sodium in your diet can lead to high blood pressure, a major risk factor for cardiovascular disease.
However, one 2014 study suggests that eating kimchi does not increase blood pressure. Also, the nitrite content of kimchi varies by the type and how it’s prepared. Depending on the preparation, you can minimize the nitrite content (59). Furthermore, the histamine content of kimchi varies by the product and how it’s produced (60). That said, purchasing the kimchi from a reliable source and correctly storing the kimchi can minimize the risk of any adverse effects. Finally, although people with high blood pressure may have concerns about this dish’s high sodium content, a study in 114 people with this condition showed no significant relationship between kimchi intake and high blood pressure (61).
Making Kimchi at Home
Although people can purchase kimchi at many grocery stores and Korean markets, they may also consider preparing it at home. Though preparing fermented foods may seem like a daunting task, making kimchi at home is fairly simple if you adhere to the following steps (3): It can be safe to make kimchi at home, but people must follow proper sanitation practices to prevent contamination by spoilage or harmful bacteria. This will involve proper hand-washing, using clean equipment, and cleaning surfaces throughout all preparation steps.
To safely prepare kimchi at home:
- Prepare the cabbage: Rinse the cabbage and discard any spoiled or damaged spots. Cut the cabbage into quarters and remove the core from each. Then, chop these quarters into 2-inch (in) pieces.
- Salt the cabbage: Prepare a saltwater solution, comprising half a cup of salt and 1 gallon of cold water, in a large mixing bowl. Briefly dip the cabbage in the saltwater solution, then discard the salt water. Place the cabbage in a bowl. Sprinkle over some salt, then massage it into the cabbage. Allow the cabbage to sit at room temperature for 3-6 hours. Rinse the cabbage three to four times with cold water, then place it in a colander for 30 minutes.
- Prepare the seasonings: Add sweet rice flour to half a cup water in a saucepan. Bring to a boil and set aside to cool. Clean, peel, and finely mince the garlic and ginger. Mix with the cooled sweet rice flour paste and add Korean red pepper powder. Clean and peel the radish, green onions, and Asian pear. Slice into matchsticks about 1 in in length. Using clean hands, mix the seasoning paste and vegetables together in a large mixing bowl. Then, mix in fish sauce to create a veggie paste.
- Combine the cabbage with the spicy veggie paste, rub together, and mix thoroughly.
- Pack the container: Pack the kimchi tightly into the container, minimizing air exposure and encouraging brine formation. Fill the container about two-thirds full with kimchi and cover tightly. If using jars, seal them fingertip tight. If using bags, squeeze out any excess air.
- Fermentation: Place the kimchi in the refrigerator so that it ferments slowly over 3-4 days. This may be preferable, especially during hot weather. Alternatively, place the sealed container in a well-ventilated location with a relatively constant room temperature. Ferment for only 1-2 days at room temperature, tasting it daily until it reaches one’s preferred taste and desired texture.
- Storage: People can now store the kimchi in the refrigerator. It is important to cover it tightly to minimize air exposure. Kimchi may become more sour and spoil over time. Discard the kimchi if there are any signs of mold or if it develops a strong, foul odor.
Gather ingredients of your choice, such as cabbage and other fresh vegetables like carrot, radish, and onion, along with ginger, garlic, sugar, salt, rice flour, chili oil, chili powder or pepper flakes, fish sauce, and saeujeot (fermented shrimp). Cut and wash the fresh vegetables alongside the ginger and garlic. Spread salt in between the layers of cabbage leaves and let it sit for 2-3 hours. Turn the cabbage every 30 minutes to evenly distribute the salt. Use a ratio of 1/2 cup (72 grams) of salt to every 6 pounds (2.7 kg) of cabbage. To remove the excess salt, rinse the cabbage with water and drain it in a colander or strainer. Mix the rice flour, sugar, ginger, garlic, chili oil, pepper flakes, fish sauce, and saeujeot into a paste, adding water if necessary. You can use more or less of these ingredients depending on how strong you want your kimchi to taste. Toss the fresh vegetables, including the cabbage, into the paste until all of the veggies have been fully coated. Pack the mixture into a large container or jar for storage, making sure to seal it properly. Let the kimchi ferment for at least 3 days at room temperature or up to 3 weeks at 39°F (4°C). To make a version that’s suitable for vegetarians and vegans, simply leave out the fish sauce and saeujeot. If you prefer fresh over fermented kimchi, stop after step 6. If you choose fermentation, you’ll know that it’s ready to eat once it starts to smell and taste sour - or when small bubbles begin to move through the jar. After fermentation, you can refrigerate your kimchi for up to 1 year. It will continue to ferment but at a slower rate due to the cool temperature. Bubbling, bulging, a sour taste, and a softening of the cabbage are perfectly normal for kimchi. However, if you notice a foul odor or any signs of mold, such as a white film atop the food, your dish has spoiled and should be thrown out.
How to Enjoy Kimchi
Kimchi is a versatile dish that people can add to many meals. People can eat it as a side dish, use it as an ingredient in other meals, or eat it on its own. Kimchi is a dietary staple of Korean diets, and for good reason.
Some ways that people can enjoy kimchi include:
- Served on top of potato pancakes
- Used as a filling in an omelet
- Stirred into homemade fried rice
- Used inside burritos and Korean-style tacos
- Added to noodle dishes such as ramen, udon, and soba
- Used to flavor soup broth
People can eat it as a side dish, use it as an ingredient in other meals, or eat it on its own. Although individuals can cook kimchi, keep in mind that heating any fermented foods can start to kill off the healthy probiotics. So, to retain the health benefits, it is best to add kimchi in at the end of the cooking process.