Health Benefits of Probiotics

Probiotics offer a range of health benefits. They are part of the healthy intestine microflora, they boost your immune system, they synthesize certain vitamins, and they help you fight off common infections and colds. New research shows that they may help with metabolic syndrome and diabetes, and contribute to healthy weight loss.

What are Probiotics

For centuries, folk tradition suggested that fermented dairy product, containing live bacteria, can be beneficial for our health. Recent scientific research has proven this to be true and it is now clear that probiotics should be an integral part of a healthy diet. But what exactly are probiotics?

Experts define probiotics (definition by The Food and Agriculture Organization of the United Nations) as "live microorganisms, which, when administered in adequate amounts, confer a health benefit on the host".

The word probiotic is derived from the Greek word pro, which means "promoting" and biotic, which means "life".

Probiotics are mostly bacteria, but the group also includes some types of yeast. Probiotics are often called the good or beneficial bacteria as they contribute to health (contrary to bad bacteria, which are pathogenic microorganisms that cause disease).

Many probiotics are naturally found in your body, especially in the gut. You can also find probiotics in cultured or fermented foods (such as yogurt, certain cheeses, sauerkraurt, etc) and probiotic supplements, containing live cultures.

The most common probiotics come from 2 groups: Lactobacillus and Bifidobacterium. These probiotics are normal inhabitants of gut microflora.

When considering probiotics, you need to be aware that there are many different types and strains of probiotics– each with its own properties and benefits to human health.

It is estimated that there are more microbes residing in human body than there are human cells in it. The number of microorganisms is 1014, while the number of human cells is 10 times lower: 1013.

How Do Probiotics Work?

Within our gastrointestinal tract, we have over 400 bacterial species that collectively form our gut microflora. Most of these bacteria live in the colon, but some can be found in the stomach and the small intestines.

These microorganisms can act in several ways: positive, neutral or negative. Maintaining the right balance between the beneficial and harmful microorganisms is essential for your health. Bad diet, antibiotics overuse, stress, medications, environmental toxins, or diseases can all tip the scale in favor of the so-called bad bacteria. This is where probiotics come into play.

Probiotics help us in several ways – they support the development and healthy functioning of the gastrointestinal tract, they enhance the function of the immune system, and help us alleviate the symptoms of allergies in both children as well as adults.

Let’s take a look at how probiotics work in your body:

Probiotics positively alter the conditions in your gut flora

Probiotics, like Lactobacillus and Bifidobacterium, produce certain substances (for example lactic acid and acetic acid), which make the colon slightly acidic. This creates an environment that inhibits the growth of many harmful bacteria and prevents them from attaching to the gut lining. Probiotics also steal food sources from these bacteria, which further slows down their reproduction.

They strengthen the barrier function of the intestinal lining

Probiotics strengthen the mucus on the intestinal lining. This decreases the passage of harmful microbes and toxins from the intestines into the blood stream. It has been suggested that this function is the reason why probiotics help us fight infections and decrease allergy reactions to food.

Probiotics boost your immune system

The digestive tract is estimated to contain 70% of the body’s immune system. Probiotics increase the activity and concentration of certain immune cells and thereby directly influence the action of the immune system.

Probiotics aid in digestion

Probiotics help us absorb nutrients and digest food. This, in turn, alleviates some digestion problems, such as gas and bloating.

Probiotics help produce B vitamins

Probitics are actively involved in the synthesis of the B group vitamins. These vitamins are essential for the normal functioning of the nervous system. They also contribute to healthy vision and skin; they are involved in the production of red blood cells, and help us convert glucose to energy.

Probiotics help with side effects of antibiotics therapy

Many people experience diarrhea and stomach pain after antibiotic use. Probiotics can help prevent this or ease the discomfort.

They improve lactose tolerance

Probiotics, especially, Lactobacilli produce substances (lactic acid) that aid lactose digestion.

Probiotics Can Help With These Conditions

Probiotics are most often used for alleviating the symptoms of digestive conditions. Among them are:

Irritable Bowel Syndrome (IBS)

People with IBS suffer from diarrhea, constipation, or alternating bouts of both. They often report stomach cramps, pain, gas or bloating. Studies have found that probiotics can help with the symptoms of IBS; most commonly reported were decreased diarrhea and abdominal pain.

Inflammatory Bowel Disease

There are 2 main types of inflammatory bowel disease: Chrohn’s disease and ulcerative colitis. They are both diseases of the immune system, which cause inflammation of the intestines. Symptoms include pain, diarrhea, weight loss, and blood in stools. Recent research has shown that high levels of certain probiotics may help keep inflammation under control and prolong the periods during which the disease is in remission. Some study results suggest that ulcerative colitis may be more responsive to probiotic supplementation.


There are several types of diarrhea: infectious diarrhea, which is caused by viruses, bacteria or parasites, antibiotic-related diarrhea that comes from antibiotic use, and diarrhea experienced by travelers.

There is lots of evidence that probiotics (particularly Lactobacillus rhamnosus and Lactobacillus casei) help with infectious diarrhea. Best effects have been observed in children, suffering from rotavirus.

 Antibiotic diarrhea is the result of the reduced number of normal bacteria in the gut due to antibiotic use. Taking probiotics (especially Saccharomyces boulardii) immediately at the start of antibiotic therapy may prevent antibiotic-related diarrhea. If you have already developed diarrhea, probiotics may shorten its duration and decrease the severity.

Another common form of diarrhea is traveler’s diarrhea. Studies show that probiotic supplementation is a safe and effective method for preventing and lessening the symptoms of traveler’s diarrhea.

Helicobacter Pylori

Helicobacter pylori is a bacterium that is found in the stomach. It causes stomach ulcers and cancer. Studies have been made in which probiotics have been given in addition to the usual antibiotic therapy for Helicobacter Pylori. In these studies, probiotics have alleviated the side effects of antibiotics and increased the rate of eradication of Helicobacter Pylori.

Lactose Intolerance

People who don’t have enough lactase (the lactose-digesting enzyme) suffer from symptoms of lactose intolerance. These include bloating, abdominal discomfort, gas, and diarrhea. Probiotic products aid the digestion of lactose. The reason for this is that they contain lactic acid, which breaks down the lactose before it reaches the colon. That is why many lactose intolerant people are able to consume fermented dairy products (such as kefir or yogurt) without experiencing uncomfortable side effects.

Probiotics are also indicated in cases of stomach ulcers, acid reflux and spastic colon. They, however, may also help with some non-stomach related conditions. These include:

Brain function, Anxiety and Depression

Lately it has become evident that gut microflora may influence brain function. If we consider that gut is called our ‘second brain’, this doesn’t sound so far-fetched. The communication between brain and gut is a two-way street. We all know that emotions, such as fear, stress and anxiety, are felt in gut. However, what comes as a surprise is that gut is able to control pain and emotion - to a certain degree, of course.

Probiotics have been shown to influence this gut – brain communication. In studies, people taking probiotics reacted more calmly to stress; they were more focused on problem solving and less on negative aspects of situation. That is why probiotics are being studied for use in mood disorders, anxiety, and depression.


Studies suggest that consumption of probiotics may decrease cancer risk. Probiotics help prevent cancer through several actions:

  • they help you detoxify cancer-causing chemicals (carcinogens) ingested with food,
  • they change the intestinal environment in a way that inhibits the growth of bad bacteria, which generate toxic substances,
  • probiotics themselves produce substances which help programmed cell death (a process, called apoptosis is a way for a body to remove old cells),
  • they enhance the immune system to help the body defend against cancer cells.


Studies suggest that Lactobacilli help lower high blood pressure. 

Weight Loss, Metabolic Syndrome, and Diabetes

It has been found that people suffering from obesity, metabolic syndrome and diabetes have disrupted gut flora. The link between gut flora composition and these conditions still needs to be studied – to find out whether you can help these conditions by changing the types of microbes that are prevalent in the intestines.

Experimental studies in humans have shown that probiotics (a strain of Lactobacillus gasseri) caused a decrease in total fat and BMI (body mass index) in diabetic patients. Other studies that were focused on insulin resistance have shown promising results with regards to increased sensitivity of cells to insulin.

Vaginal Infections

The vagina has its own complicated microflora. This micro ecosystem can be disrupted through hormonal imbalance (for example, pregnancy puts you at higher risk for vaginosis), antibiotic use, diet high in junk food and sugar, spermicides, illness, and stress.

It has been shown that a lack of lactobacilli in vagina is a risk for vaginal infections. The lactobacilli, namely, keep the environment in the vagina slightly acidic, which inhibits the growth of harmful bacteria and yeast (including Candida). When the ph levels in the vagina are off, vaginal infections become much more likely.  Oral and vaginal probitics that restore vaginal microflora have been shown to help with bacterial vaginosis, yeast infection, and urinary tract infections.

Other Uses

Probiotics have also been successfully used for atopic eczema, childhood respiratory conditions, dental problems such as tooth decay and halitosis (bad breath), high cholesterol, asthma, and for boosting the immune system in general.

Are Probiotics Safe?

Probiotics are dietary supplements, which means that they are not regulated in the same way as medications. They fall under the Dietary Supplement Health and Education Act of 1994 (DSHEA). This act requires that the supplement is safe before being put on the market. The FDA gets involved only after the product is already being promoted and found to be unsafe.

It is generally believed that probiotics are safe and cause little negative side effects. Most common side effects are mild gas and bloating, which usually get better once the body gets used to the new gut microflora.

Probiotics might be potentially dangerous to people with suppressed immune system, due to illness or chemotherapy, to people with conditions with the potential for leaky bowels, including acute pancreatitis, and to premature infants. Some probiotics may also interfere with certain medications, so always consult your doctor before starting a new supplement regime.

Probiotics have been shown very helpful in cases of infectious diarrhea and food allergies in children. If you want to give your child probiotics, always discuss this with their pediatrician.

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