For many years after the microscope was invented, bacteria were thought to be always a bad for your body. Even now in our modern world, the concept of bacteria being always unhealthy is carved in our way of thinking. But recent findings about bacteria show that this is not always the case. There are actually good sources of bacteria, and they can be beneficial sometimes.
Why are bacteria beneficial, how can you choose good bacteria, and where can you find them naturally?
What are good bacteria and why should you care?
Good bacteria are also known as healthy bacteria or normal flora. All body surface that has direct or indirect contact with the environment has bacteria. The best example is the skin, which is in contact with all types of fluids and environmental conditions. But good bacteria is also seen in the gastrointestinal tract, because even if it doesn’t have direct contact with the outside world, it does receive food with plenty of bacteria in it.
The reason we are still healthy despite being surrounded and in contact with bacteria is that we have good bacteria taking care of us in the skin and mucosa. In the gut, the proportion of bacteria that populates this area can be compared with the world’s population. Good bacteria maintain the balance in this environment and does not allow harm from pathogenic or bad bacteria.
Moreover, good bacteria can contribute to the metabolism in the body. They create anti-inflammatory substances, improve the responsiveness of the immune system, and may even contribute to weight control and symptoms of depression. In the gut there’s a potent connection to the brain and the lymphatic system that mediates all of these effects, and recent research has made clear that gut microbiota is much more important than we originally thought.
Sure, not all bacteria are appropriate for the gut. The most common healthy microbiota comes from the Lactobacillus species, but others include Saccharomyces and Bifidobacterium. Some of them are yeast instead of bacteria, but perform a similarly beneficial function to the gut and our entire health.
Good bacteria in food sources
Where can you find good bacteria for your gut? Fermented foods are probably the best source you can have. When we think about fermented food, the first option that comes to mind is yogurt. It is probably the most widely consumed, and popular in all types of diet. Even people with lactose intolerance can consume yogurt, unless they have a very severe condition.
Yogurt can have plenty of bacteria, but the most common is Lactobacillus acidophilus. These bacteria are purposefully added to milk during the manufacturing process to obtain yogurt. However, some types of yogurt are treated by heat after completing the fermentation process, and this destroys all good bacteria. Thus, if you’re considering yogurt as a source of good bacteria, take a look at the label and check whether or not it provides Lactobacillus acidophilus bacterial cultures or any others.
Besides yogurt, there are many other fermented foods you have probably not tried, and they are also great sources of good bacteria for your gut. For example:
- Kefir: You can get kefir from milk, just like yogurt. But the process of making kefir is through a combination of bacteria and yeast cultures. It is similar to yogurt in this regard, but has more bacterial strains, it is a diverse and potent probiotic, and probably much better than the so-famous yogurt.
- Tempeh: This fermented food comes from Indonesia and it is a soy-based product treated with probiotic strains. It has many nutrients and provide an excellent source of good bacteria.
- Miso: This is a popular Japanese seasoning prepared with fermented soybeans. It is popularly consumed in miso soup, and there are different types and variations of the recipe.
- Natto: Another Japanese food prepared with fermented soybeans, Natto is consumed with rice and contains a type of healthy bacteria known as Bacillus subtilis.
- Kombucha: This one is not a food but a probiotic drink. It is fermented green or black tea. It is colonized by bacteria and yeast, and very popular in Asian countries.
- Kimchi: This is another probiotic food made of cabbage, but it can be prepared with other vegetables. It comes from Korea, and the most abundant bacteria is Lactobacillus kimchii.
- Sauerkraut: This fermented food is typical in many places of Europe, and commonly served with sausages. It is basically fermented cabbage and mostly has lactic acid bacteria. Similar to yogurt, you can find heat-treated sauerkraut that destroys all bacterial cultures, so it is recommended to look at the label.
- Pickles: You probably know pickles. They are no more than cucumbers prepared in a salty solution and left to ferment. Pickles are a great source of lactic acid bacteria, and has plenty of nutrients on top of that.
Good bacteria in supplements
Probiotic supplements are an alternative way to get healthy bacteria for your gut. It is an appropriate source if you want to have more control on the dose of bacteria, and if you want to combine different strains of bacteria to achieve better results. They are commonly prescribed when you need to take a heavy dose of antibiotics to counter Clostridium difficile infections. But these supplements can be found as over-the-counter products and are free to use with no significant adverse effects.
Every time you’re choosing a new probiotic, look carefully at the label and consider the bacteria it offers. In most cases, they should give you a minimum of 1 billion CFU, or colony forming units.
You can combine probiotic foods with supplements with no problem, and another interesting combination is fiber, because some types of fiber are food for bacteria and help them grow in your gut. There are preparations of a special fiber known as prebiotics, which can be combined with probiotics to make them more effective.
The best thing about feeding your gut with probiotics is that they are not bad for you in any way, and won’t cause significant side effects. Some people experience temporary bloating, but that’s only a minimal sign that goes away after a while, especially if you’re using a natural source of good bacteria.
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Granato, D., Branco, G. F., Cruz, A. G., Faria, J. D. A. F., & Shah, N. P. (2010). Probiotic dairy products as functional foods. Comprehensive reviews in food science and food safety, 9(5), 455-470.
Granato, D., Branco, G. F., Nazzaro, F., Cruz, A. G., & Faria, J. A. (2010). Functional foods and nondairy probiotic food development: trends, concepts, and products. Comprehensive reviews in food science and food safety, 9(3), 292-302.