Life Extension Magazine®

Researcher with beaker filled with gut micro probiotics for whole body benefits

Surprising Effects of Probiotics Outside the Intestinal Tract

Imbalance of gut bacteria can do more than induce intestinal or digestive problems — it may be a catalyst for diabetes, cardiovascular disease, cancer, obesity, and respiratory infections. Two of the most studied probiotics have been shown to restore healthy gut bacteria, improve cell signaling, enhance immune function, and block pathways that lead to chronic conditions.

Scientifically reviewed by Dr. Gary Gonzalez, MD, in May 2022. Written by: Michael Downey, Health & Wellness Author.

Surprising Effects of Probiotics Outside the Intestinal Tract

Typically we think of probiotics as only benefitting intestinal health. We are now learning that having the proper balance of healthy gut bacteria plays a role in protecting against a wide range of common disorders.1-21

Modern Western culture can deplete good bacteria in our gut. Everything from diet to antibiotics to excessive hygiene creates an imbalance of good-to-bad bacteria. Once the good bacteria are destroyed, bad bacteria quickly multiply and open the door for degenerative diseases.

Fortunately, strong evidence demonstrates that taking the right mix of probiotics can restore your body’s natural protection against a host of diseases.1-20

How Intestinal Imbalance Affects the Entire Body

How Intestinal Imbalance Affects the Entire Body  

So why is it that an imbalance in gut bacteria affects areas of the body outside of the intestines?

The answer lies in the fact that the intestinal tract contains more chemical detection and signaling molecules than any other organ—molecules that affect many aspects of health.22

Your intestinal bacteria produce proteins that have a powerful influence on these chemical detectors—and as with any influence, this one can be positive or negative.23 Over time, an imbalance in the ratio of good-to-bad bacteria activates these many detectors in negative ways that can trigger the development of a host of diseases in many body areas—not just those associated with the gut.

Fortunately, using probiotic supplements to restore a healthy balance to your gut bacteria can reverse these disruptions to intestine-based signaling mechanisms. This in turn reverses the negative influence that triggers the development of chronic disease.24

Total Body Benefits

It has long been known that good gut bacteria have a number of beneficial effects on intestinal health.22 For example, Lactobacillus and Bifidobacteria, two of the most studied types of beneficial bacterial, have been shown to improve both diarrhea and constipation, while reducing symptoms of abdominal bloating.25-27 Probiotic supplements that increase levels of these beneficial bacteria have helped improve both the quality of life and symptom scores of patients with irritable bowel syndrome (IBS) and ulcerative colitis, as well as those of generally healthy people.26,28-30

But compelling new evidence indicates that good bacteria also play a beneficial role outside the digestive tract as well.1-20 Scientific studies have demonstrated that different species of Lactobacillus (Lactobacillus acidophilus, Lactobacillus rhamnosus, and Lactobacillus paracasei) increase HDL,31 improve metabolic syndrome,31 and reduce markers of inflammation, respectively.31

In addition, different Bifidobacterium species (Bifidobacterium lactis, Bifidobacterium bifidum, and Bifidobacterium longum) improve blood sugar control,32 decrease liver inflammation,31 and reduce DNA damage that can trigger malignant cell development,33 respectively.

Probiotics Protect Against Chronic Diseases

Probiotics Protect Against Chronic Diseases

Numerous studies have confirmed that taking a probiotic supplement to restore the balance of gut bacteria helps protect against a number of specific diseases, including diabetes, cardiovascular disease, and respiratory infections.34

Studies have shown that probiotics containing Lactobacillus and Bifidobacteria help improve diabetes and metabolic syndrome. In fact, both animal studies and human clinical trials have demonstrated improvement in insulin resistance and reduction in blood sugar concentrations.32,35,36 After just 6 weeks of consuming a probiotic yogurt containing Lactobacillus acidophilus and Bifidobacterium lactis, type II diabetics significantly improved fasting glucose and hemoglobin A1c (a measure of blood sugar control).32

Animal and human studies have demonstrated that probiotics improve cardiovascular disease factors as well, including decreasing total cholesterol and LDL while boosting artery-cleansing HDL.35,37-44 Supplements of beneficial bacteria have been shown to reduce cholesterol absorption and the inflammation of fat stores.45,46 These changes contribute to a significant decrease in the formation of inflammatory, cholesterol-laden plaques observed in early atherosclerosis.45,47,48

In addition, studies have shown that probiotics can suppress respiratory infections such as the common cold and the flu—especially if you begin supplementing prior to cold and flu season. Studies show that people who supplemented with different strains of Bifidobacteria or Lactobacillus for 3 to 6 months ahead of the winter cold and flu season reduced the duration of symptoms by an average of one to two (or even more) days, with a similarly impressive reduction in symptom severity.49,50

Regular use of probiotics has been found to reduce colonization of the nose by potentially pathogenic bacteria by 19%.51 This effect could save the lives of those who are older, or who have diabetes, or who have undergone a major operation—all of whom have a higher risk of being overwhelmed by bacterial infection.

The Powerful Role of Probiotics in Cancer

Probiotics have been found to be incredibly potent against one deadly disease in particular: cancer. The risk of cancer, especially in the colon, can be reduced through the use of probiotics.52 Supplementation with Lactobacillus acidophilus and Bifidobacterium longum significantly decreases the DNA damage that can trigger malignant cell development.33 Replenishing beneficial bacteria with supplements has been found to boost natural antioxidant and detoxification enzymes that prevent the activation of potential dietary carcinogens.52,53

Patients with colon cancer and those with pre-cancerous polyps had sharply reduced proliferation of abnormal colon cells and a significant decline in harmful Clostridium bacteria when supplemented with synbiotics (probiotic bacteria combined with prebiotics, which are substances that feed or promote the accompanying bacteria).54

In addition, scientists have demonstrated that probiotic organisms switch-on protective signaling mechanisms that play a role in preventing cancer, including:

  • Suppressing bacteria that convert harmless pro-carcinogen molecules into carcinogens.55,56
  • Binding to potential carcinogens, promoting their excretion.55
  • Down-regulating an enzyme that converts harmless molecules into carcinogens.55
  • Stimulating expression of liver enzymes that detoxify carcinogens.55
  • Boosting populations of cells that seek out and destroy cancers.56-58
  • Upregulating inflammatory cytokines during an acute stage of cancer or other threat.56,59
  • Suppressing the inflammatory response as the cancer or infection threat fades.56,59

Probiotics Help Reverse Obesity

An association between antibiotic overuse and obesity has been demonstrated, which can be reversed with appropriate probiotic supplementation.60 Studies of probiotic supplementation on both research animals and humans showed a significant reduction in body weight and body mass index (BMI).35,37-44 In one study, probiotic supplements were given to mothers prenatally (meaning from about five months before, and until one month after, birth), and excessive weight gain was subsequently reduced in the mothers—and in their children from birth right through to 10 years of age!61,62

Factors Behind Gut Imbalance

Factors Behind Gut Imbalance  

There are a number of factors that contribute to a dangerous imbalance of gut bacteria. The excessive use of antibiotics disrupts the optimum proportions of gut bacteria; excessive hygiene has drastically reduced our ability to naturally acquire certain key bacteria from our environment;63 and a number of modern medical treatments such as artificial ventilation, tubes and catheters, and frequent pharmaceutical use, are known to severely impair the proper balance of gut bacteria.64

The Western diet—high in animal proteins and fats, sugars, and refined carbohydrates—causes a rise in undesirable bacteria. Even the modern use of infant formula instead of breast milk has interfered with mankind’s long history of transferring bacterial diversity from mother to child.63,65 Recent findings suggest that even aging itself disrupts the bacterial makeup of the gut.66-68

Although good bacteria can be found in small amounts in food, changing the entire ratio of gut bacteria requires substantial and consistent dosing with supplements providing potent levels of bacteria to enable their survival.

Also, while many supplements provide just one type of bacteria—the most popular being Lactobacillus—the combination of two different types delivers better odds of reversing the negative effects of dysbacteriosis, a condition where healthy gut bacteria are killed off leaving an imbalance between good and bacteria. Bifidobacterium is another potent bacterium that strongly supports microflora.


Scientists have shown that a prolonged imbalance in intestinal bacteria can do more than induce intestinal or digestive problems—it can trigger numerous chronic diseases outside the intestine!

The link between imbalanced intestinal bacteria and today’s most prevalent diseases is clear. However, today’s diet, lifestyle, medical practices, and other factors tend to disrupt gut bacterial balance.

Fortunately, supplementing with key bacterial strains counters these destructive influences—restoring your body’s natural, intestine-based protection against a host of non-intestinal diseases!

If you have any questions on the scientific content of this article, please call a Life Extension® Health Advisor at 1-866-864-3027.


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