Fermented foods: Should they be part of your diet?

Humans have been fermenting foods for thousands of years. Fermentation protects foods from spoiling and produces foods with a pleasing taste and texture. Asian and African cultures use fermentation as a way to have seasonal foods all year, and to ensure there is enough to eat during food shortages.

Food trends often spread across the world, so people from all over the globe have experienced fermented foods and made them part of their diets. As a result, more research is being done on the role of fermented foods in health, which has increased their popularity and availability.

What is fermentation?

Fermentation is a process that uses bacteria and yeast to convert sugars to carbon dioxide, alcohol, and lactic acid. The process also produces energy. The type of bacteria or yeast used during fermentation can produce different flavors and textures of food.

Salt also plays an important role in the fermentation process. It inhibits the growth of harmful bacteria and enhances the flavor of the fermented food.

Health benefits of fermented foods

Fermented foods may be beneficial to your health. Here's why:

• Fermentation may help the body absorb a food’s antioxidants, such as the polyphenols and flavonoids found in red cabbage. Antioxidants are essential for your body to heal and grow.
• Fermentation can help remove unwanted substances, such as toxins, from food. Take the plant cassava, for example. It is commonly used to make the Sudanese dish kawal. It releases cyanide during digestion if it's eaten raw. Fermentation breaks down this poisonous substance so it's safe to eat.
• Fermented foods contain probiotics. These are live bacteria added to foods to trigger fermentation. Probiotics are good bacteria that can help keep your gut healthy. They help make sure that the unfriendly bacteria don't overtake the friendly bacteria.

How probiotics can help

The balance between friendly and unfriendly bacteria in your gut are important for

• digestion
• absorption of nutrients
• immune function
• metabolism.

And your diet affects the balance of bacteria in your gut.

The Western diet tends to be high in saturated and trans fats, sodium, and refined carbohydrates. It's also low in fruits, vegetables, whole grains, and healthy fats. Research suggests that this type of eating pattern changes gut bacteria, which may contribute to obesity, cancer, and inflammatory bowel disease.

Eating fermented foods on a regular basis may help to maintain or restore a healthy gut. Research has shown that probiotics can help manage or prevent infectious diarrhea, antibiotic-related diarrhea, and traveler's diarrhea. Other research has shown that probiotics can help to reduce the severity of diseases such as irritable bowel syndrome (IBS) and ulcerative colitis (UC). Further, replacing highly processed foods that are high in fat, sodium, and refined carbohydrates with fermented foods may also help aid in weight management.

Examples of fermented foods

Fermented foods can be added to a balanced diet that includes protein, grains, fruit, vegetables, and dairy.

• Fermented dairy products. Look for the ingredients Lactobacillus bulgaricus and Streptococcus thermophilus in yogurt, cheeses, and kefir. These products can be found in major grocery store chains and come in a variety of flavors. They also contain calcium and vitamin D, which are essential for bone health.
• Soy products. Miso, soy sauce, and tempeh are fermented soy products. Tempeh is a source of protein for people who follow vegetarian or vegan diets. It has an earthy, nutty flavor. Soy products are available in major grocery stores.
• Fermented vegetables. Sauerkraut (pickled cabbage) and kimchi (a Korean version of sauerkraut) are examples of fermented vegetables. Both are sold in major grocery stores. Kimchi is most often found in Asian markets.

Fermented food considerations

Fermented soy and vegetable products are high in sodium. They should be avoided or strained well if you have high blood pressure, heart disease, or impaired kidney function.

Also, not all fermented foods contain live bacteria or probiotics. For example, fermented vegetables such as sauerkraut that are sold in grocery stores have been heated to a very high temperature. This kills all the bacteria present in the food. So, check the Nutrition Facts label for the phrase "contains live and active cultures." Or make your own!

The bottom line

Fermented foods are good sources of fiber, antioxidants, minerals, and vitamins (including calcium, potassium, vitamin D, folate, and B vitamins). All are part of a balanced diet.

The research surrounding the beneficial role of probiotics is growing. Fermented foods that have live and active bacteria may be helpful for weight management, reducing the risk and severity of intestinal infections, and reducing the symptoms associated with IBS and UC. When choosing fermented foods, pay attention to sodium content and make sure the product contains live and active cultures.

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