Probiotics, as defined by the WHO, are "live microorganisms (especially bacteria found in certain foods or supplements) that, when taken in adequate amounts, can provide health benefits to the host."
What's the difference between probiotics and lactic acid bacteria?
They're often confused or used synonymously, but they're not the same thing. Lactic acid bacteria are bacteria capable of producing lactic acid from the fermentation of lactose, like most probiotics. However, once ingested, they don't survive the passage through the stomach. Probiotics, however, do. They remain alive throughout the entire journey, from the mouth to the intestine.
The intestine is the primary site where probiotics work. They influence the balance of the intestinal microbiota—the community of bacteria, viruses, fungi, and protozoa (400 different species, up to a kilogram and a half in total) that populate the digestive tract. The microbiota is home to both "good" bacteria (such as Bifidobacteria and Lactobacilli) and "bad" bacteria (such as Enterococcus faecalis and Clostridium difficile). It's essential for our body's health that these microorganisms live in balance (a condition called eubiosis). It's important that the beneficial bacteria maintain the upper hand, meaning that intestinal dysbiosis doesn't develop. This is because scientific findings indicate that diseases such as irritable bowel syndrome, inflammatory bowel disease, allergies, obesity, diabetes, and depression are linked to our gut bacteria.
The term "probiotic" translates as "for life." Foods are described as probiotic if they contain microorganisms that enter our intestines in sufficient quantities and have positive health effects. These microorganisms include, for example, lactic acid bacteria such as lactobacilli and bifidobacteria, as well as certain yeast fungi.
The unique feature of probiotic yogurts is that only probiotic lactic acid bacteria are used as starter cultures, or are added later (after the fermentation process). These lactic acid bacteria can pass through the stomach unharmed and settle in the intestine.
The goal is for the probiotic bacteria to multiply in the intestine and replace the "unfavorable" bacterial cultures present. This promotes healthy intestinal flora.
The following foods are considered the richest in probiotics:
1. Plain yogurt is one of the best sources of probiotics. It can improve intestinal flora and help with conditions such as diarrhea or constipation. Yogurt also has much to offer in other ways: Nutrition societies recommend regular consumption of dairy products like yogurt because they provide our bones with optimal calcium and our muscles with high-quality protein. Some studies suggest that plain yogurt can even prevent high blood pressure. All the health benefits come from plain yogurt! Ready-made fruit yogurt is usually high in sugar, so it should be considered more of a dessert. When purchasing, look for traditionally produced dairy products that have not been pasteurized. The same goes for vegan yogurts: only unheated products contain lactic acid bacteria.
2. Kefir: This traditional Turkish dairy product is made from sheep, goat, or cow's milk. In addition to lactic acid bacteria, the kefir tuber is used for fermentation—that is, it contains both lactic acid bacteria and yeast. Like yogurt, kefir can improve bone density and help with digestive problems. Thanks to its high content of various vitamins, minerals, and essential amino acids, kefir is said to have numerous other health benefits. These include, for example, antimicrobial and anti-inflammatory effects and positive effects on sugar and fat metabolism. Traditional kefir is almost lactose-free. Therefore, people with lactose intolerance can usually tolerate it well.
3. Cheese: Live lactic acid bacteria are mainly found in cheddar, Gruyère, Gouda, mozzarella, and Parmesan. Generally, the older the cheese, the more probiotic bacteria it contains. However, it's important to note that live probiotic bacteria are only found in unpasteurized cheeses! They are killed during the heating process. So pay attention to the information on the packaging: manufacturers indicate whether their products are heat-treated.
4. Sauerkraut is made by fermenting white or pointed cabbage. The cabbage is chopped, mashed, salted, and stored in an airtight container. Lactic acid bacteria, which are usually present in the cabbage, convert the fructose contained in the cabbage into lactic and acetic acid. Sauerkraut juice (also known as brine) can also be added as a starter to ensure rapid and even fermentation. After 10-14 days, the cabbage has fermented and is called fresh cabbage. This "raw" sauerkraut contains many probiotic bacteria and is particularly suitable for vegans. Sauerkraut is high in vitamin C and high in dietary fiber, which aids digestion. Important: Only fresh sauerkraut contains lactic acid bacteria and vitamins. Pasteurized sauerkraut from a can or jar contains neither vitamins nor probiotic bacteria due to the heating process. Traditionally produced fresh sauerkraut can be found, for example, in health food or organic stores.
5. Sour cucumbers (also called pickled cucumbers) are prepared in a mixture of water, herbs, sugar, and salt. Lactic acid bacteria settle on the cucumber skin and then produce lactic acid, which preserves the cucumbers. Thanks to their high content of probiotic lactic acid bacteria, sour cucumbers promote regular digestion. One study also suggests that cucumber water can relieve muscle cramps and prevent sore muscles.
6. Apple cider vinegar is made from apple juice with the help of yeasts and lactic acid bacteria. The microorganisms first ferment the juice into apple cider. The alcohol is then converted into acetic acid, producing apple cider vinegar. Apple cider vinegar is said to have various positive effects on the body. For example, it is believed to aid weight loss, lower blood sugar levels, and reduce the risk of cardiovascular disease. So far, however, no studies have been able to clearly demonstrate these effects. However, apple cider vinegar contains probiotic bacteria as well as many vitamins, minerals, trace elements, and enzymes, making it very healthy. Tip: Buy high-quality, naturally cloudy, unfiltered, unpasteurized, and unfiltered organic apple cider vinegar.
7. From Asian cuisine: tempeh and miso: Tempeh is very similar to tofu: to make it, soybeans or grains are brined and fermented by lactic acid bacteria. Tempeh has a meat-like consistency and is tasteless and odorless. In addition to probiotic bacteria, tempeh contains a lot of easily digestible protein and a high content of minerals such as magnesium, potassium, and phosphorus. Miso is a Japanese spice paste made from soybeans and grains such as rice or barley. During the long maturation process (often over a year), lactic acid bacteria ensure that the paste ferments and acquires its characteristic flavor. Traditionally produced miso not only contains many probiotic lactic acid bacteria, but also high in protein and dietary fiber.
8. Kombucha: Kombucha is a fermented tea popular in Asian medicine. A blend of special bacterial strains, yeasts, and the kombucha mushroom is added to sweetened black tea or herbs. During fermentation, alcohol, acetic acid, lactic acid, and gluconic acid are produced—a beverage similar to mash with carbonic acid. Kombucha has a tart flavor and contains between 0.7 and 1.3% alcohol.
Kombucha is said to have numerous positive effects. Among other things, it is said to help with gout, rheumatism, blemished skin, and even protect against cancer and cardiovascular problems. However, these effects have not yet been confirmed in scientific studies. It's also important to know that kombucha often contains large amounts of caffeine and sugar in addition to alcohol. Industrially produced kombucha, which you can buy at the supermarket or health food store, has been pasteurized and no longer contains probiotics. You can also make kombucha yourself, but you must pay particular attention to hygiene. Kombucha contaminated with foreign germs, especially mold, can cause problems for sensitive individuals, especially those with immune deficiencies.
(Article by Dr. Cristina Giusto, nutrition biologist)
