7 Fermented Foods That May Improve Gut Health

One of the biggest health trends in recent years is fermented foods—and we're not just talking about that familiar jar of pickles or sauerkraut found in many Israeli kitchens.

An increasing number of nutrition experts, physicians, and microbiome researchers believe there is a strong connection between gut bacteria and overall health, including the immune system, digestion, and even mood. One of the simplest ways to support a healthy gut microbiome may be by regularly eating fermented foods.

So what exactly are fermented foods, what are their potential benefits, and how can you add them to your diet without upsetting your digestive system?

Fermentation is a natural process in which beneficial bacteria or yeast break down sugars and carbohydrates in food. This changes the food's flavor, texture, and sometimes even its nutritional value. However, it's important to know that not every fermented food still contains live bacteria by the time you eat it. Products that are pasteurized after fermentation often lose most of their beneficial live cultures, even though they retain the same taste.

Why Are Fermented Foods So Popular?

Research suggests that regularly eating a variety of fermented foods may help increase the diversity of the gut microbiome, support healthy digestion, and, in some people, reduce markers of inflammation. While scientists are still studying exactly how these foods affect long-term health, the findings so far are encouraging.

Many people also report feeling less bloated, more satisfied after meals, and experiencing improved digestion after gradually incorporating fermented foods into their diets.

Fermented Foods Worth Trying

Plain yogurt
Unsweetened yogurt containing live cultures is one of the easiest ways to add natural probiotics to your diet.

Kefir
This fermented milk drink contains a wide variety of beneficial bacteria and yeasts. It has a pleasantly tangy flavor and is considered one of the richest sources of natural probiotics.

Naturally fermented cabbage (sauerkraut)
Choose cabbage that has been naturally fermented rather than simply pickled with vinegar. Unpasteurized sauerkraut still contains live beneficial bacteria.

Naturally fermented pickles
Look for pickles fermented in a saltwater brine rather than those preserved in vinegar.

Kimchi
This traditional Korean dish is typically made from cabbage, garlic, ginger, and spices. It has a spicy, bold flavor and is naturally rich in beneficial bacterial cultures.

Kombucha
A fermented tea with a distinctive taste. Choose varieties that are low in added sugar, and enjoy it in moderation.

Miso
A traditional Japanese paste made from fermented soybeans that is commonly used in soups, sauces, and marinades.

How to Introduce Fermented Foods

One of the biggest mistakes people make is eating large amounts of fermented foods right away.

Instead, begin gradually. Start with a few spoonfuls of yogurt, a small serving of sauerkraut, or one fermented pickle, then slowly increase the amount over time.

This gives your digestive system time to adjust and may help reduce temporary gas or bloating.

Can Everyone Eat Fermented Foods?

For most people, fermented foods are perfectly safe and can be part of a healthy diet.

However, individuals with certain digestive disorders, histamine intolerance, or severely weakened immune systems should consult a physician or registered dietitian before making significant dietary changes. People with high blood pressure should also be mindful of the sodium content in foods such as sauerkraut and fermented pickles.

Can Fermented Foods Replace Probiotic Supplements?

Not necessarily.

Fermented foods and probiotic supplements serve different purposes. Supplements contain specific bacterial strains in carefully measured amounts, while the types and quantities of bacteria found in fermented foods naturally vary from batch to batch.

For most healthy people, regularly eating a variety of fermented foods can be an excellent way to support gut health. In certain medical situations, however, a healthcare professional may recommend a probiotic supplement instead.

An Easy Place to Start: Homemade Sauerkraut

One of the easiest fermented foods to make at home is naturally fermented cabbage, also known as sauerkraut. Besides being inexpensive and delicious, it can be an excellent source of beneficial bacteria.

Ingredients

• 1 large white cabbage (with reliable kosher supervision and checked for insects)
• Coarse, non-iodized salt (20 grams per kilogram of cabbage, or about 2% of the cabbage's weight)

Instructions

1. Wash your hands and all utensils thoroughly.
2. Remove the outer leaves, core the cabbage, and separate the leaves.
3. Soak the leaves in water with a designated fruit and vegetable wash, then rinse well.
4. Slice the cabbage into thin strips.
5. Place it in a large bowl, add the salt, and massage for 5 to 10 minutes until the cabbage softens and releases plenty of liquid.
6. Pack the cabbage tightly into a clean, sterilized glass jar, pressing firmly to remove air pockets.
7. Make sure the cabbage is completely covered by liquid. If needed, prepare a brine by dissolving 20 grams of salt in one liter of water and add enough to fully submerge the cabbage.
8. Seal the jar with a tight-fitting lid.

How Long Does It Take?

• Summer: 3 to 7 days
• Winter: 7 to 14 days, sometimes longer

Taste the cabbage daily. Once it reaches a pleasantly tangy flavor, transfer it to the refrigerator, where the cold temperature will greatly slow the fermentation process.

How to Tell If It's Fermenting Properly

Healthy fermentation usually includes:

• Small bubbles in the liquid.
• A pleasantly sour aroma.
• Cabbage that remains fully submerged.
• Slightly cloudy liquid.

Discard the batch if you notice:

• Black, blue, green, or pink mold.
• A rotten or foul odor.
• An unusually slimy texture.

Tips for Success

• Always use a glass jar rather than a metal container.
• Keep the cabbage completely submerged throughout fermentation.
• Avoid salt containing iodine or anti-caking agents, as these may interfere with fermentation.
• For extra flavor, try adding caraway seeds, black peppercorns, garlic, ginger, or bay leaves.

Properly stored in the refrigerator and kept covered by its brine, homemade fermented cabbage will usually remain fresh for several months.