Fermented foods can boost the amount of beneficial gut bacteria (probiotics) in your body. Probiotics are linked with certain health benefits that include improved digestion and immunity, and may even help increase weight loss.

Here are 8 fermented foods that may help improve your health and digestion.

1. Kefir

Kefir is a fermented dairy product that is made by adding kefir grains (a combination of yeast and bacteria), to milk. This makes a thick drink that tastes somewhat like yogurt, and studies have shown that drinking kefir could help improve digestion, reduce inflammation, and improve bone health.

One study showed that kefir helped improve the digestion of lactose in 15 people who suffered from lactose intolerance. This condition makes the body unable to digest sugars in dairy products, and results in symptoms like cramps, bloating and diarrhea.

Another study showed that those who consumed 200 ml of kefir daily for six weeks had decreased inflammation markers, which are a known contributor to diseases such as heart disease and cancer.

Kefir could also help improve bone health, and one study found that kefir improved the bone mineral density of a group of 40 people with osteoporosis.

Kefir can be consumed by itself, or added to smoothies.

2. Tempeh

Tempeh is a cake made from fermented soybeans that have been compressed. It’s a high-protein substitute for meat, and has a firm but chewy texture. It can be baked, steamed, or sautéed, which makes it very versatile.

It has a high probiotic content, and is also rich in nutrients such as soy protein, which may reduce some risk factors for heart disease.

One study showed that people with high cholesterol who at soy protein had a 5.7% decrease in harmful LDL cholesterol, a 4.4% reduction in total cholesterol and a 13.3% reduction in blood triglycerides.

Another test-tube study found that some plant compounds in tempeh may act as antioxidants and reduce the free radicals that can lead to chronic diseases.

Tempeh can be used in sandwiches, stir-fries, and many other dishes as a meat-free protein alternative.

3. Natto

Natto is a Japanese food that is also made from fermented soybeans, and it contains plenty of fiber too – 5 grams per 100 gram serving.

Natto is also high in vitamin K, which is involved in the metabolism of calcium and has a key role in keeping bones healthy. A study of 944 postmenopausal women showed that natto consumption was linked with reduced bone loss.

The fermentation process of natto produces an enzyme called nattokinase, which can help prevent and dissolve blood clots. One study also found that taking supplements of this enzyme helped reduce blood pressure.

Natto has a strong flavor and is often served with rice as part of a healthy Japanese breakfast.

4. Kombucha

Kombucha tea is a fermented, fizzy beverage. It is usually made from black or green tea and contains their health benefits.

Animal studies on liver toxicity show that drinking kombucha can prevent damage caused by exposure to harmful chemicals, while test-tube studies have found that it could block the spread of cancer cells and induce cancer cell death.

Kombucha may even reduce blood sugar, triglycerides, and LDL cholesterol, according to an animal study.

Kombucha can be bought at major grocery stores, and you can also make your own at home with the right equipment.

5. Miso

Miso is used as a seasoning in Japan, and is made from fermented soybeans with added salt and koji (a type of fungus).

It’s most famously found in miso soup, a dish made of miso paste and stock that is often served for breakfast.

As well as having a good probiotic content, miso may have health benefits. One study of women showed that consuming miso soup was linked to a lower risk of breast cancer.

Miso has also been associated with lowering blood pressure, and with a lower risk of stroke.

You can have miso in soup, or try using it to marinate meat, in salad dressings, or to glaze cooked vegetables.

6. Kimchi

Kimchi is a Korean side dish made from fermented vegetables – usually cabbage, but radishes and other vegetables are sometimes used.

Kimchi may be very effective at lowering cholesterol and reducing insulin resistance. A study of 21 people with pre-diabetes showed that those who ate fermented kimchi had decreased insulin resistance, blood pressure, and also showed weight loss.

Kimchi can be made at home very easily, and is great added to noodle bowls, sandwiches, or eaten on its own.

7. Sauerkraut

Sauerkraut is a popular dish of shredded cabbage fermented by lactic acid bacteria. It is low calorie, high fiber, and contains vitamins C and K, as well as lutein and zeaxanthin. These two antioxidants reduce the risk of eye disease and help keep eyes healthy.

The antioxidants in sauerkraut may also help prevent cancer. A test-tube study showed that when cabbage juice was used to treat breast cancer cells, it decreased the activity of certain enzymes that are related to cancer formation.

Sauerkraut can be used to top sandwiches, added to soup and casseroles, or used as a side dish. You can make sauerkraut at home very easily with cabbage, salt, water, and a large glass jar.

8. Probiotic Yogurt

Yogurt is made from fermented milk, and contains key nutrients including calcium, potassium, phosphorus, riboflavin, and vitamin B12.

A review of 14 studies found that fermented milk products like probiotic yogurt may help reduce blood pressure, and another study found that older adults who ate more yogurt had improvements in bone mineral density and physical function.

Not all yogurts contain probiotics, as food processing often kills these bacteria. Look for yogurts that are labeled probiotic, and that contain live cultures.