Shaun Ward MSc ANutr
Sauerkraut is a finely cut raw cabbage that has been fermented by various lactic acid bacteria that are naturally present on cabbage leaves.
Fermenting foods can make them richer in probiotic bacteria and therefore can add good bacteria and enzymes to the intestinal flora when consumed. This process is associated with the health of the gut microbiome and immunity.
Due to this, sauerkraut offers nutrition and health benefits far beyond that of fresh cabbage. The fermentation process also means sauerkraut has a distinct flavor and aroma.
The use of sauerkraut dates back centuries, with ancient writings from Hippocrates describing this food as part of his health and medicinal routines. In todays world, sauerkraut is not a popular food in many cultures, however it is still often mentioned in health magazines and articles for its unique benefits.
1. May Improve Gastrointestinal Health
Sauerkraut is thought to boost gastrointestinal health by adding good bacteria to the gut, with research showing that just one serving contains up to 28 distinct bacterial strains .
75 grams of sauerkraut daily for 6 weeks has shown to significantly reduce gastrointestinal issues in people with irritable bowel syndrome. In addition, based on an analysis of fecal microbiota of these individuals, it was shown that sauerkraut had caused beneficial changes in the diversity of bacterial communities in the gut .
Much lower doses for shorter periods, such 3.5 grams per day for 4 weeks, have also shown positive effects for reducing the frequency and severity of gastrointestinal issues in these patients .
It is hypothesized that the natural content of complex carbohydrates in fermented sauerkraut gives the product its strong prebiotic properties – such as from galacto-oligosaccharides and fructooligosaccharides.
Also, it is plausible that other substances besides bacteria, such as dietary fibers or glycosinolates present in sauerkraut can act therapeutically in the treatment of irritable bowel syndrome.
In particular, sauerkrauts content of probiotics may act as the first line of defense against toxins and harmful bacteria . Numerous studies also conclude that probiotics help gastrointestinal issues such as reducing gas, bloating, constipation, diarrhea .
2. May Improve Immune Function
Closely linked to gastrointestinal health, maintaining a healthy gut flora also helps prevent the growth of harmful bacteria and may even boost the production of natural antibodies.
The probiotics and prebiotics found in sauerkraut are both suggested to improve the composition of bacteria in the gut. In turn, this keeps a strong gut lining and prevents ‘leaky gut syndrome’ – where toxic waste products and bacteria can pass through the intestines and enter the blood stream.
A weak gut lining that allows unwanted substances to enter the blood stream is known to cause an immune response and increase the vulnerability to pathogens .
In addition, sauerkraut is also high in vitamin C and iron, both of which contribute to a healthy immune system .
3. May Protect Against Cancer
Protecting against cancer is one of the major aims of every healthcare system across the world.
Sauerkraut may protect cancer formation as it contains a high content of certain compounds that have shown to decrease DNA damage and cell mutation rates in cancer patients, such as glucosinolates, ascorbigen, and ascorbic acid .
However, depending on nature of fermentation, sauerkraut tends to have extremely different concentrations of these compounds between products.
At least in regard to ascorbigen content, the highest concentration seem to be observed in sauerkraut that has lower levels of sodium .
It is also important to note that the evidence for sauerkrauts effect on cancer is not conclusive, and there are even studies that have found that sauerkraut increases the risk factor for cancer . More research is needed to observe this relationship.
4. Good Nutrient Profile
Sauerkraut contains many nutrients that are important for optimal health. 100 grams provides: 
- Vitamin C: 24% of the recommended daily intake
- Vitamin K: 17% of the recommended daily intake
- Iron: 8% of the recommended daily intake
- Manganese: 8% of the recommended daily intake
Sauerkraut also contains a small, yet notable amount of vitamin B6, folate, calcium, magnesium, and potassium, that can contribute towards daily requirements for these micronutrients.
Also, sauerkraut is very low in calories and therefore an individual can increase their vitamin and mineral intake without digging too deep into their caloric intake. Win win!
5. May Reduce the Risk of Heart Attacks
Sauerkraut may reduce the incidence of heart attacks because it contains a significant amount of fiber and probiotics, both of which may help to reduce cholesterol levels and maintain a flow of blood to the heart.
Research demonstrates that probiotics can synthesize acids – when they digest dietary fiber in the colon - that fight against the production of cholesterol. Namely, the most well-known acid to achieve this is proprionic acid which reduces the production of cholesterol in the liver .
Probiotics can do this by breaking down liver bile acids, which the liver produces from cholesterol. In turn, the liver has to make additional bile acids, thus using up more cholesterol in the process and reducing overall cholesterol levels .
Due to this reduction in cholesterol levels, it is less likely that plaques will be formed on arterial walls that would typically restrict blood vessels, reduce blood flow, and increase the risk of heart attacks .
Beware of Allergies
Aged or fermented foods such as sauerkraut contain high concentrations of histamine, a compound within food that many people cannot tolerate without side effects.
Histamine intolerances usually result in symptoms such as an increased heart rate, mild hypotension, sneezing, and itching of the nose. In more severe cases, it can result in diarrhea, flatulence, and headaches.
For this reason, high intakes of sauerkraut in sensitive people might result in similar reactions, and those that are intolerant to histamine may wish to avoid its consumption .
Sauerkraut is a type of fermented cabbage by various lactic acid bacteria, that is high in fiber, probiotics, vitamin C, vitamin K, iron, and manganese.
This food may improve gastrointestinal health and immune function, and also decrease the risk of heart attacks and cancer.
However, individuals that are sensitive to histamine should avoid consuming it as the fermentation process of sauerkraut leads to high histamine concentrations.