Runny nose. Congestion. Sore throat.

These upper respiratory tract symptoms can be due to the common cold, influenza, or environmental allergies.^1,2

Scientists have found a probiotic and a postbiotic that can tackle these upper respiratory tract symptoms.

In a clinical trial, a specific probiotic strain cut the incidence of colds and flu by more than half compared to a placebo.³

Additionally, a placebo-controlled trial of individuals with seasonal allergies showed that a postbiotic strain of yeast reduced days with nasal congestion by 43% during high pollen counts.⁴

Combining these ingredients can help support respiratory health throughout the year.

Respiratory System Under Attack

Upper respiratory tract symptoms are common:

• Adults average two to four colds a year,¹
• Influenza afflicts up to 11% of Americans annually,⁵ and
• Allergic rhinitis (allergies) causes nasal symptoms like sneezing or congestion, and affects up to 40% of people worldwide.⁶

The flu, a common name for influenza, can be dangerous, killing tens of thousands of people in the U.S. every year.⁷

Colds are bad enough on their own but can also lead to more severe illnesses like pneumonia, especially in immune-compromised individuals.^8,9

Respiratory infections may also worsen existing conditions, including asthma and chronic obstructive pulmonary disease (COPD).¹

A clinically tested probiotic and postbiotic can help prevent and reduce the severity of respiratory illnesses.

Probiotic Defense

Lactobacillus rhamnosus CRL 1505 is a probiotic originally isolated from goat’s milk in Argentina.¹⁰

The health properties of probiotics are often unique to a specific strain.

“CRL 1505” refers to the strain of the bacteria discussed in this article.

The CRL 1505 strain of L. rhamnosus can promote immune responses in the respiratory tract as well as the gut. It is considered so beneficial to immune health that it was made part of the nutrition program for children in Argentina.¹⁰

Preclinical research shows that L. rhamnosus CRL 1505 primes the immune system to respond and helps clear infections faster.^11,12

Preventing Colds and Flu

Young children are an ideal group on whom to test the respiratory effects of a probiotic. Their immature immune system puts them at increased risk of catching colds and flu.¹³

In a large placebo-controlled trial, preschool children received 100 million CFU (colony-forming units) of L. rhamnosus CRL 1505 in yogurt five days a week for six months.¹⁰

During the study, 31% of the probiotic group had upper respiratory tract infections like colds and flu compared to 69% of those receiving a placebo yogurt, an astonishing difference.

Similarly, only 28% of children in the treatment group developed pharyngitis (sore throat) and tonsillitis, while 72% of those in the placebo group did.

Taking the probiotic also cut instances of fever nearly in half.

The study found that the treatment group had a 47% increase in levels of salivary IgA (immunoglobulin A), an antibody that protects against viruses and bacteria.¹⁴ Levels in the placebo group were unchanged from baseline.¹⁰

Boosting IgA in the respiratory tract helps prevent infections from colonizing and spreading in the body.¹⁵

Postbiotic Protection

Postbiotics are compounds produced when gut microbes ferment fiber. They can also include inactive microorganisms and their beneficial byproducts. In human studies, postbiotics have shown immune support, reduced inflammation, and improved gut barrier function.¹⁶

About two decades ago, this was illustrated when an employer discovered that factory workers manufacturing a yeast culture took significantly fewer sick days than their coworkers with desk jobs.¹⁷

The factory workers were unknowingly inhaling airborne yeast fermentate, a postbiotic, as part of their daily work.

They also had beneficial changes in their bloodwork compared to their office-based colleagues, including:

• Higher levels of secretory IgA,¹⁷ the antibody essential to the mucosal immune system’s defense against infection,¹⁴ and
• Increased activity of natural killer cells,¹⁷ immune cells that can recognize and rapidly eliminate virus-infected cells.¹⁸

Clinical trials have confirmed that a specific dried yeast fermentate promotes IgA production and natural killer cell activity.^4,19,20

In one trial in healthy adults, a single 500 mg dose of the yeast fermentate increased markers of natural killer cell activity within just two hours.¹⁹

Easing Allergy Symptoms

After the “accidental” discovery of the immune effects of this yeast fermentate, the company went on to make the postbiotic commercially. Its effects have been verified in multiple clinical trials.

The benefits of the specialized dried yeast fermentate include:

• Fewer colds and influenza. In clinical trials of healthy adults, daily intake of 500 mg of yeast fermentate reduced the incidence of cold or flu-like symptoms by up to 13% during peak cold and flu season.^21,22 It also decreased the duration of symptoms by 17%.²¹
• Reduced seasonal allergies. When adults with seasonal allergies took 500 mg of yeast fermentate daily during six weeks of high pollen counts, they had significantly milder nasal symptoms and a whopping 43% fewer days of nasal congestion than a placebo group.⁴
• Decreased effects of histamine. Histamine is one of the compounds that causes allergy symptoms. In an allergy test, the inflammatory effects of histamine were reduced by 54% in healthy adults given this yeast fermentate.²³

What You Need To Know

Fend Off Colds, Flu, and Seasonal Allergies

• Upper respiratory tract ailments, including colds, flu, and environmental allergies, are top causes of sore throats, stuffy noses, and other symptoms.
• The probiotic strain Lactobacillus rhamnosus CRL 1505 primes the immune system to respond to infections faster. In a clinical trial, it cut the incidence of colds and flu by more than half compared to a placebo.
• Placebo-controlled trials have shown that taking 500 mg daily of a specific yeast fermentate, a postbiotic, can decrease the incidence and duration of colds and flu and dramatically reduce seasonal allergy symptoms.
• A combination of these ingredients can help ward off colds, flu, and allergy symptoms year-round.

In another clinical trial, taking the specialized yeast fermentate significantly reduced the need for respiratory medications.²⁴

Combining yeast fermentate with the probiotic Lactobacillus rhamnosus CRL 1505 may provide powerful protection against symptoms of allergies, colds, and flu.

Summary

There’s a way to help counter cold, flu, and seasonal allergies.

Clinical trials have shown that the probiotic Lactobacillus rhamnosus CRL 1505 and a yeast fermentate can reduce the incidence and duration of colds and flu.

This yeast fermentate can also significantly ease symptoms of seasonal allergies.

These ingredients each bolster the immune system’s ability to quickly respond to respiratory invaders.

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

References

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