Hippocrates once said, “Let food be your medicine and medicine be your food.” This quote clearly explains the philosophy of functional food and its correlating lifestyle. Around the supermarket, you can find foods claiming that they are a good source of probiotics. What exactly does that mean? What are probiotics? How are they beneficial to us? The answer lies with fermented foods.
History
Humans have been unintentionally consuming probiotics since the creation of farming approximately 10,000 years ago. It all starts with fermentation. Although food fermentation was accidental, humans have taken advantage of this process for years. In the beginning, it was used to help increase the food’s stability. Some fermented foods were even consumed as a form of medicine. Today, fermented foods are consumed because of the tradition that comes with it. The flavor development that occurs is something that cannot be duplicated.
The relationship between microbial fermentation and human health was not investigated until the 20th century. Elie Metchnikoff, a Russian scientist at the Pasteur Institute, noticed that people who lived in rural Bulgaria consumed more fermented dairy products than an average person. They also roughly were in better health when compared to others in that age group. Metchnikoff proposed that it was their diet that helped increase their longevity. He stated that, “The dependence of the intestinal microbes on the food makes it possible to adopt measures to modify the flora in our bodies and to replace the harmful microbes by useful microbes.”
How It Works/Health Benefits
Healthy humans have trillions of microorganisms throughout their bodies. They actually outnumber human cells 10:1! These microorganisms are called the human microbiome, but this article is specifically investigating those found in our gastrointestinal (GI) tracts. The gut bacteria found in the GI tract is called the gut microbiota. The gut microbiota plays an important role in digestion and the immune system. The most common strains of bacteria found in the GI tract are Lactobacillus and Bifidobacterium. These bacteria are able to break down the foods we eat. They help nutrients become more readily available for our bodies to use.
Probiotics help our gut microbiota by increasing the number of microbes present in the GI tract. This helps diversify the colonies as well as help the bacteria that is already there. This is important because a more varied microbiota helps protect the body from harmful bacteria. It can also help aid in digestion of milk and reduce inflammation from other allergies. There are studies that claim that diversifying the gut microbiota can help with memory, cognition, and high blood pressure but there is not enough evidence to be sure.
Sources
Fermented foods are the main source of natural probiotics. Practically every civilization has some sort of fermented food in their repertoire. Fermented foods are best known for their tanginess and depth of flavor. The tang is produced by the bacteria inherently present in the food. Food producers allow a controlled breakdown of starches into simple sugars, organic acids, and potentially carbon dioxide. Helpful enzymes and B vitamins which help regulate the body’s metabolism may also be present.
Some fermented foods are yogurt, sauerkraut, miso, cheeses, tempeh, sourdough breads, buttermilk, and pickles. Yogurt is one of the most familiar fermented foods. Its characteristic texture and tang are produced by bacterial fermentation of milk. Sauerkraut is most commonly used as a sandwich topping. It is made through lacto-fermentation of cabbage. Miso is fermented soybean paste. It is mainly consumed in Japan and is full of probiotics, vitamins, and minerals. Probiotics are only useful once they are in the GI tract. Some foods are not as good vehicles as others – depends on how resistant they are to stomach acid. Soft cheeses such as Swiss, Cheddar, and Gouda are particularly good probiotic carries through the digestive system. As a vegetarian, tempeh is very familiar to me. I’ve made it in one of the undergraduate Food Science classes and eat it on a weekly basis. Tempeh is fermented soybeans pressed into a cake-like shape. I would describe tempeh as bitter and occasionally nutty. It has more of protein and fiber than tofu and has more texture/bite. Sourdough breads, buttermilk, and pickles are also everyday fermented food products.
Prebiotics/Probiotics
Probiotics, as stated above, are microorganisms consumed with the intent to diversify or increase the gut microbiota. Prebiotics are actually supplements; they can be simply described as food for your gut microbiota. They help your good bacteria grow and thrive. Pre/probiotics are not necessary for a healthy person who has a well-balanced diet and eats enough fiber. There is no recommended daily intake for pre/probiotics but the rule of thumb could be to integrate as many fermented foods as possible into your diet. For most people, taking supplements are not harmful but it is always best to consult your doctor before taking anything. Predicted minor side effects are typically at most bloating and gas. It is not recommended to give supplements to immunocompromised people or children/infants. Typically, probiotic supplements can range from 1-10 billion colony forming units (CFUs) but yogurt can have 90-50 billion CFUs! Overall, more doesn’t always equal better but research states that it wouldn’t hurt.
Final Thoughts
Even though fermentation was accidentally discovered, it has become an important part of the human diet. Most Americans consume some sort of fermented food every day – be it yogurt, sourdough bread, or pickles. It creates depth of flavor and increases the nutritional profile. Fermented foods are the best source of probiotics. They can have a good amount of some vitamins and minerals that are bioavailable too. Probiotics can help aid in digestion and strengthen your body’s immune system. In the end, pre/probiotics are not necessary if your diet is varied. Increasing the amount of fermented foods in your diet will help expand your palate. It could introduce you to other types of food you wouldn’t have even considered before while keeping your gut microbiota happy!
Resources
- https://journals.lww.com/jcge/Fulltext/2016/11001/Probiotics_History.3.aspx
- https://www.nih.gov/news-events/news-releases/nih-human-microbiome-project-defines-normal-bacterial-makeup-body
- https://health.clevelandclinic.org/prebiotics-vs-probiotics-whats-the-difference/
- https://www.webmd.com/digestive-disorders/pick-right-probiotic#2
- https://www.health.harvard.edu/staying-healthy/how-to-get-more-probiotics
- https://www.onhealth.com/content/1/probiotic_foods
