Sauerkraut from fermentation is a common and traditional form of preserving cabbage. Beware, though, that sauerkraut side effects, such as bloating, gas and digestive discomfort, are common, especially in those who are not used to fermented foods.
Sauerkraut can promote a healthy gut and it's a good source of vitamins. On top of that, it has very few calories and carbs. Along with other fermented foods, it's generally safe when consumed in moderation unless you have an intolerance or allergy to it.
What Is Sauerkraut?
Fermented food has a long tradition of consumption, dating back to the fourth century BC, according to research published in Global Advances in Health and Medicine in November 2014. Sauerkraut, or sour cabbage in German, is made from shredded cabbage heads that are naturally fermented by various bacteria.
The process of fermentation enriches foods with proteins, vitamins and essential amino and fatty acids. Sauerkraut contains large doses of vitamins A, B, C and K.
The microorganisms formed during this process convert carbohydrates in the cabbage to lactic acid, a compound responsible for the sour taste, and carbon dioxide, which produces the bubbles seen in the initial phase of fermentation. Sauerkraut is most commonly used as a side dish, but it can be added to main dishes too.
Its eastern cousin, kimchi, is derived from fermenting the stems and leaves of Chinese cabbage with additional ingredients like hot peppers, garlic, vegetables and fish sauce. Like with sauerkraut, side effects from eating too much kimchi can include digestive upset from excessive intake.
Fiber and Sauerkraut Side Effects
Sauerkraut is an excellent source of dietary fiber. But eating too much too fast if you're not used to a high-fiber diet and fermented foods, in particular, may cause side effects like diarrhea, cramping and indigestion. Introduce sauerkraut into your diet slowly and gradually increase the amount you eat over several days or even weeks to reap the benefits that fiber provides for digestive health.
According to the USDA, one cup of sauerkraut supplies 4 grams or 16 percent of the fiber needed to meet the daily amount recommended by the 2015-2020 Dietary Guidelines for Americans. A typical serving of sauerkraut would likely be around half a cup or 120 grams.
Dietary fiber keeps your digestive system functioning smoothly. Your body cannot break down this nutrient, so it passes through your system relatively intact, slowing down digestion and adding bulk to your stool. Fiber not only keeps you regular, but it may alleviate the symptoms associated with hemorrhoids, irritable bowel syndrome (IBS) and diverticulitis.
Furthermore, it may reduce your risk of colon cancer, according to a review published in the American Journal of Clinical Nutrition in August 2015.
Sauerkraut Nutritional Value
Sauerkraut can fit perfectly into most weight loss plans. It is low in calories — only 27 per cup — and has no fat or cholesterol. With its high fiber content, it keeps you full longer and may help prevent overeating. If you're on a low-carb diet, sauerkraut is a good choice as it has only 6.1 grams of carbohydrates in one cup.
Although its protein content is minimal and offers only 3 percent of your daily value (DV) per cup, sauerkraut contains many important vitamins and minerals that contribute to optimal health. This fermented food is rich in B vitamins and potent antioxidants. Some of the vitamins in one cup of sauerkraut include:
- Vitamin C: 20.9 grams or 23 percent of your DV — an antioxidant needed to support your immune system
- Vitamin K: 18.5 milligrams or 15 percent of the DV — essential for blood clotting
- Vitamin A and E: 1 percent of the DV each — serve as antioxidants
The B group of vitamins are essential to convert foods into energy needed for the healthy functioning of your muscles, brain, nervous system, blood cells and skin.
- Thiamine: 2 percent of the DV
- Riboflavin: 2 percent of the DV
- Niacin: 1 percent of the DV
- Vitamin B5: 3 percent of the DV
- Vitamin B6: 11 percent of the DV
- Folate: 9 percent of the DV
Sauerkraut boasts an impressive mineral content in each cup, including:
Calcium: 42.6 milligrams or 3 percent of the DV — for your teeth and bones
Iron: 2.1 milligrams or 12 percent of the DV — for proper production of red blood cells
Potassium: 241.4 milligrams or 5 percent of the DV — needed for fluid balance to maintain a steady heartbeat and proper muscle contraction
Magnesium: 18.5 milligrams or 4 percent of the DV — regulates blood pressure; helps build healthy teeth and bones
Phosphorus: 28.4 milligrams or 2 percent of the DV — builds and protects bones
Zinc: 0.3 milligrams or 2 percent of the DV — essential for taste, smell and wound healing
Copper: 0.1 milligrams or 15 percent of the DV — helps make red blood cells and plays a role in your immune system
Manganese: 0.2 milligrams or 9 percent of the DV — helps metabolize carbohydrates, amino acids and cholesterol
Selenium: 0.9 milligrams or 2 percent of the DV — acts as an antioxidant and helps regulate thyroid hormone activity
Watch the Salt Content
Despite all the nutritional health benefits of sauerkraut, its high sodium content may pose certain risks. Salt is necessary for the preparation of sauerkraut to regulate fermentation, which makes it a high-sodium food.
Sauerkraut contains 938.6 grams of sodium, or 39 percent of the daily value, per cup. The 2015-2020 Dietary Guidelines recommend limiting total sodium intake to no more than 2,300 milligrams daily.
Too much sodium in your diet can contribute to elevated blood pressure and increase your risk of heart disease and stroke. An increase in blood sugar levels can also damage your kidneys over time and lead to kidney failure, warns the National Kidney Foundation. Excessive salt may also cause calcium losses, some of which may be taken from your bones.
If you are on a sodium-reduced diet, you can reduce some of the salt content of sauerkraut, as well as the tartness, by rinsing it in cold water before using.
Probiotics and Digestive Health
Fermented foods like sauerkraut and kimchi contain probiotics. These are live microorganisms resulting from fermentation by lactic acid bacteria. They are beneficial for the gastrointestinal system due to their ability to bolster healthy digestive flora. To get the maximum benefit, look for sauerkraut varieties made from naturally fermented and unprocessed vegetables.
Probiotics may be effective for the treatment of diarrhea, constipation, IBS and urinary infections, according to a research paper published in Functional Foods in Health and Disease in August 2016. Researchers have found that homemade sauerkraut provides the recommended amounts of beneficial bacteria.
In addition, the World Journal of Gastroenterology published a meta-analysis in March 2015 that included 1,793 patients with symptoms of IBS, such as abdominal distension, bloating and gas. Scientists concluded that probiotics may reduce pain and IBS symptoms to a greater extent than placebo.
Eat Sauerkraut for Stronger Bones
When your bones start to lose tissue and become brittle, you risk developing osteoporosis. Although calcium is often most associated with bone health, sauerkraut also contains many other minerals that help build strong bones and increase their density. These include vitamin K, magnesium, potassium, phosphorus, copper, iron and zinc.
The vitamin K in sauerkraut produces certain compounds that contribute to bone mineralization, maintaining the integrity of your bones. It also regulates calcium, supporting the structure and hardness of your teeth and skeletal system.
About 50 to 60 percent of the magnesium in your body resides in your bones, so eating sauerkraut can help maintain bone health and lower the risk of osteoporosis in post-menopausal women, says the National Institutes of Health. Potassium, another important mineral, benefits bone health by reducing calcium loss.
A study published in the Nutrition Journal in March 2015 has found that adequate intakes of phosphorus and calcium improved bone mineral content. Additionally, this combo led to a 45 percent reduction in the risk of osteoporosis.
Read more: 13 Surprising and Beneficial Probiotic Foods
Other Benefits and Side Effects
Fermented foods, such as sauerkraut, are continuously being researched to discover new health benefits from the probiotics and other compounds they contain. According to the National Center for Complementary Integrative Health, some of these include the possible prevention of:
- Oral health problems, including periodontal disease and tooth decay
- Liver disease
- The common cold
- Serious intestinal illness in very low birth weight infants
Although side effects from probiotics are rare and generally only consist of mild digestive symptoms, such as gas and diarrhea, sauerkraut contains a high amount of histamine. This compound may increase the risk of allergic reactions, especially in people with food sensitivities and those suffering from hay fever, according to the review in Global Advances in Health and Medicine.
A high intake of sauerkraut may result in some of these symptoms:
- Diarrhea or flatulence
- Itchy skin
- Increased heart rate
- High blood pressure
- Sneezing, runny nose
The study reported that the concentration of histamine in sauerkraut is dependent on the method of preparation and may range considerably. Further research is needed to confirm intolerance, allergic reactions or other unwanted side effects from eating too much kimchi or sauerkraut.
- Colorado State University: Farm to Table Food Safety: "What is Sauerkraut?"
- Mayo Clinic: "Dietary Fiber: Essential for a Healthy Diet"
- MyFoodData: "Nutrition Facts for Sauerkraut"
- Health.gov. "Dietary Guidelines for Americans, 2015-2020: Appendix 7. Daily Nutritional Goals for Age-Sex Groups Based on Dietary Reference Intakes and Dietary Guidelines Recommendations"
- International Foundation for Gastrointestinal Disorders: "Dietary Fiber"
- Mayo Clinic: "Q and A: Diet, Lifestyle Choices Can Lower Risk of Diverticulosis Developing Into Diverticulitis"
- American Journal of Clinical Nutrition: "Dietary Fiber Intake and Risk of Colorectal Cancer and Incident and Recurrent Adenoma in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial"
- Harvard T.H. Chan School of Public Health: "Salt and Sodium"
- National Kidney Foundation: "Top 10 Tips for Reducing Salt in Your Diet"
- Biotechnology Research International: "Fermented Fruits and Vegetables of Asia: A Potential Source of Probiotics"
- Functional Foods in Health and Disease: "Sauerkraut: A Probiotic Superfood"
- World Journal of Gastroenterology: "Effectiveness of Probiotics in Irritable Bowel Syndrome: Updated Systematic Review With Meta-Analysis"
- National Center for Complementary Integrative Health: "Probiotics: In Depth"
- Global Advances in Health and Medicine: "Regular Consumption of Sauerkraut and Its Effect on Human Health: A Bibliometric Analysis"
- National Institutes of Health: "Vitamin K"
- National Institutes of Health: "Magnesium"
- Osteoporosis International: "Dietary Potassium Intake Is Beneficial to Bone Health in a Low Calcium Intake Population: The Korean National Health and Nutrition Examination Survey"
- Nutrition Journal: "Association Between Phosphorus Intake and Bone Health in the NHANES Population"
- Calcified Tissue International: "Vitamin C and Zinc Intakes Are Related to Bone Macro Architectural Structure and Strength in Prepubescent Girls"
- Oregon State University: Linis Pauling Institute: "Copper"