Probiotics have been in the spotlight for some time now, all thanks to their gut health benefits. But now companies are marketing the popular supplement with other health benefits as well. During the peak of cold and flu season, you may see more claims about probiotics supporting the immune system. But how do probiotics affect immunity? Is there any real benefit?
ContentHow do probiotics affect immunity? The gut and immune system are closely linked. Which probiotic strain is best to take for immune support?
WomanEL understands that you may be skeptical. That's why we decided to share the opinion of experts on this matter, namely the nutritionist Miguel Freitas.
How probiotics affect immunity?
Dr. Freitas says that when taking probiotics to support your immune system, it's important to understand that the benefits of probiotics depend largely on the strain you take. This means that not all probiotics have the same health benefits. For example, one probiotic may fight bloating, while another may fight constipation.
Some research suggests that certain strains of probiotics may help your immune system. But exactly how these strains support immunity is still under investigation, says Dr. Freitas. For now, “it’s thought that probiotics may interact directly with immune cells in the gut or produce certain substances that mediate this cross-talk,” he adds. But that’s just a theory. And scientists still have a lot to learn about the possible connection.
In addition to working directly with immune cells in the gut, research has shown that probiotics can potentially boost immunity in other ways, including:
- By producing substances that kill harmful microorganisms.
- Compete with harmful microorganisms and toxins for attachment to the intestinal wall, which prevents them from gaining a foothold in the intestine.
- Promoting the survival of intestinal cells.
- Increasing the barrier function of the intestine (i.e. how strong and healthy the intestinal lining is).
- Stimulating the protective reactions of intestinal cells to foreign substances.
- Strengthening innate immunity (the body's first reaction to harmful, foreign substances).
- Effects on inflammation caused by harmful microorganisms through immune cell signaling pathways.
The gut and the immune system are closely related
“Many people are surprised to learn that 70 percent of our immune system is in our gut,” says Dr. Freitas. But it’s true. Along with the trillions of microbes that live in our digestive tract, there are immune cells that help us fight off foreign bacteria and viruses that can make us sick.
So it makes sense that prioritizing your gut health (and the balance of good and bad bacteria that live there) can also help support your immune system and other microbiomes in your body—including those on your skin, mouth, and vagina.
Bottom Line: Taking probiotics won’t completely protect you from a cold or the flu. But it can help support your immune system, which is actively fighting off disease. “The more we learn about the gut microbiome, the more we can use it to benefit your health,” adds Dr. Freitas.
What strain of probiotic is best to take for immune support?
“Since probiotic benefits depend on the strain, you should look for a product that contains a strain of bacteria that has been clinically proven to support the immune system,” says Dr. Freitas. One example of a probiotic that has been extensively studied and shown to be linked to immune function is Lactobacillus casei DN-114,001.
You can find probiotic supplements with this particular strain. But before trying them, ask your doctor if they’re right for you. They can recommend specific brands that contain quality ingredients and have been third-party verified.
When it comes to dosage, Dr. Freitas says the number of colony-forming units (CFUs)—a measure of probiotics—needed to achieve a specific benefit depends on the strain of the probiotic, as well as what amounts have previously been studied in clinical trials.
While recommended dosages can range from 100 million to over a trillion CFU per day, most probiotic strains have been studied for use at between one and 10 billion CFU per day.
Want to know what the health trends will be in 2025? Here we have listed some of them.
