Many people have heard that drinking a cup of yogurt after a meal can help with indigestion. Other products containing probiotics and prebiotics are advertised with similar claims, but are probiotics really that effective?
The Human Body: A Paradise for Bacteria
From the day we are born, the human body is a paradise for bacteria. Even for someone who is "hygienic" to the point of being a germaphobe, an adult's body still contains about 1.5 kilograms of bacteria. In the small intestine, there's still plenty of space with relatively few bacteria, about 1,000 per milliliter. But by the time you reach the large intestine, a "bacterial explosion" occurs, with hundreds of billions of bacteria in every milliliter.
The vast majority of these bacteria live in harmony with the human body. A small, restless portion may play pranks, disrupting the "ecological environment," and are known as "pathogenic bacteria." Others, with a stronger sense of responsibility, uphold the belief that "the rise and fall of the gut is the bacteria's responsibility." They metabolize to produce small-molecule organic acids, peptides, and vitamins that are beneficial to the human body, and they can also inhibit the proliferation of pathogenic bacteria. For this, they are granted the glorious title of "probiotics."
Supplementing with Probiotics: Quantity and Activity Are Key
Aiming to suppress evil and promote good, people naturally think of "supplementing" the body with probiotics to improve health. In the past few decades, thousands of related studies have been published. For conditions like diarrhea, immunity, allergies, cancer, and women's health, many positive experimental results have emerged. Fortunately, there have been almost no reports of side effects to date. Regrettably, although current research has made tremendous progress, there is still a long way to go before it can truly and reliably benefit humanity.
To benefit from probiotic supplementation, you must have "specific bacteria," "maintain their activity," "have a sufficient quantity," and "take them continuously." The number of probiotics needed to achieve an effect varies greatly. Some can work with 100 million per day, while others require 1 trillion.
As mentioned earlier, the effectiveness of probiotics requires "sufficient quantity" and "maintaining activity." For consumers, there are currently no quality standards or legal testing for the probiotics in products, so manufacturers' claims can only be guaranteed by their reputation.
Changing the Approach: Feeding the Good Bacteria
The idea of supplementing probiotics is to consume live bacteria directly. In addition, people have also thought of supporting the good bacteria by providing them with the food they love, thereby suppressing the bad bacteria. Food components that can achieve this are generally called "prebiotics."
This concept was not proposed until 1995 but immediately garnered significant attention. In the years since, more and more related research has emerged, and a considerable number of foods claimed to be "prebiotics" have been brought to market.
Their basic characteristics are: they must reach the large intestine intact, meaning they cannot be digested in the stomach and intestines; they must not only be metabolized and utilized by "good bacteria" but also not by "bad bacteria"; and after being metabolized by good bacteria, they must bring clear benefits to the human body. To date, the three most widely recognized substances that meet the "prebiotic" criteria are inulin, fructo-oligosaccharides (FOS), and galacto-oligosaccharides (GOS).
The so-called "golden bifidus factor" in some ads is not a bacterium, but a prebiotic. The term "bifidus factor" refers to a food component that helps the growth of bifidobacteria but offers no help to other bad bacteria. The word "golden" is just a marketing gimmick.
Products that mix prebiotics and probiotics are called "synbiotics," often translated as "synbiotics." According to manufacturers, the "golden bifidus factor" is actually a type of FOS. Generally, several grams of FOS need to be consumed daily to show a prebiotic effect. Some people are also intolerant to FOS, and even 1 gram can cause gastrointestinal discomfort. As for how much FOS is in these drinks, it can only be trusted to the manufacturer's word.
In fact, FOS is also found in many fruits and vegetables, such as bananas, onions, garlic, wheat, and tomatoes. If you are hoping for the beneficial effects of FOS, supplementing with these fruits and vegetables is also a good choice.
【Summary】
Whether it's "a bottle of yogurt after a meal aids digestion" or "a certain active lactic acid bacterium, have a bottle after a meal," these are not considered rumors. From a scientific perspective, they are "quite plausible."
If you enjoy the flavor, there's no harm in drinking it. However, consumers should be aware: the feasibility in a scientific concept is a different matter from the claims made in product advertisements.
Probiotics and prebiotics cannot replace medicine, so don't over-obsess over their so-called effects.