Here's how your gut and your allergies could be linked.
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If you're up on your health and wellness news, you know that gut health has been linked to both physical and mental health and that probiotics are one of the most popular ways to boost your microbiome—the collection of bacteria living in your gut. In fact, it often seems like probiotics are recommended to help treat virtually *every* health issue, from acne to digestive troubles to depression. So why not seasonal allergies too? Here's what experts have to say on the topic. (And FYI, here's more info on the surprising way your brain and gut are connected.)
How Allergies and Your Gut Are Linked
If you have allergies, you probably already know that allergies and your immune system are linked. But what may surprise you is that the connection between your gut and seasonal allergies is actually quite strong. "We live because of air, food, and water intake," explains Gregor Reid, Ph.D., chief scientist for the soon-to-be-launched Seed. The gut is considered the center of our immune system, which also spans our airways, skin, and other parts of our bodies. "This system was built from birth by microbes that taught the immune cells to know the differences between part of the 'family' and foreign invaders," Reid says. "Pollen, for example, is like one of those invaders for some people, and the system detects it and responds by trying to flush it out. Thus, sneezing watery eyes and nose." This set of symptoms is also known as allergic rhinitis.
So... Do Probiotics Help With Allergies?
While the gut is definitely implicated in allergies, it's a bit of a leap to conclude that because your gut and your allergies are related, taking probiotics will help ease your seasonal symptoms. But research does suggest there might be something to the idea.
"Although the exact mechanism isn't understood, probiotics may help promote the regulatory rather than inflammatory immune response to allergens," says Elisa Illing, M.D., an otolaryngologist (ENT) and head and neck surgeon at Indiana University Health. In other words, probiotics might help your body avoid that "allergic" response you normally have to dust, pollen, mites, or whatever your seasonal allergy triggers are.
"Several randomized, controlled trials have shown the benefit of oral probiotics in the treatment of seasonal allergies in adults and children. However, this is in addition to traditional allergy treatment with antihistamines and nasal steroid sprays," says Dr. Illing. So basically, probiotics can help, but you probably don't want to ditch your regular allergy meds just yet.
And while anyone familiar with medical research can tell you that it's possible to find a study that "proves" virtually anything, the studies on this topic are relatively solid. "The level of evidence to support the idea that probiotics may help with seasonal allergies is actually quite high," she notes. "Approximately 28 randomized, controlled trials and systematic reviews published since 2002 demonstrate improved quality of life and nasal/eye allergy symptom scores for probiotic use compared to placebo."
Of course, all studies have limitations, and the symptoms of allergies (runny nose, itchy eyes, headache) are pretty subjective, so it's important to take this research with a grain of salt. Still, the studies are very promising.
Not All Strains Are Created Equal
Of course, there are many different kinds of probiotics out there, all featuring different "strains," or types of bacteria. Different strains have been shown to help with different health issues, and allergies are no exception. "The most commonly studied probiotics for treating seasonal allergies include Lactobacillus and Bifidobacterium species, with 19 and six studies, respectively," says Dr. Illing. "Other probiotics may also be helpful, but the data is lacking to recommend for or against other strains." (BTW, here's more info on how to find the best probiotic for you.)
It's important to note, though, that thanks to the uniqueness of each person's gut bacteria, different strains might work for different people. "Our gut microbial pattern is just as unique as our fingerprint," says Will Bulsiewicz, M.D., aka The Gut Health M.D. "There is no one on the planet who has the exact same mix and proportions of bacteria that you do! The challenge is understanding which bacteria strains will fill a needed void or sway the balance in a positive direction on an individual basis given this level of bio-individuality.
There may also be some benefit to eating probiotic-rich foods if you're trying to soothe allergies. "The studies on the connection between probiotics and the prevention of allergic rhinitis are, more than anything, showing us that gut health is critical to the immune system," says Dr. Bulsiewicz. While there haven't been studies that specifically show that probiotic-rich foods soothe allergies, a healthy gut generally contributes to a healthy immune system, he explains. Therefore, foods that contribute to a healthy gut are likely to contribute to a healthy immune system as well.
Still, if you're really suffering, a probiotic pill may be your best immune-boosting option. "Many fermented foods, like most yogurts and even sauerkraut, do not have strains of bacteria that survive your stomach acid," says Michael Roizen, M.D., Cleveland Clinic's Chief of Wellness. Clinically tested probiotics, on the other hand, are made to survive that trip through your digestive system.
So where does this leave us? At the end of the day, doctors do think probiotics can have benefits for people dealing with allergies. Dr. Illing says she recommends probiotics to patients in addition to conventional medicine for seasonal and perennial allergies since the potential for benefit is real.
But it's important to note that probiotics shouldn't be the first or only thing you try to deal with your allergies. "It's unrealistic to expect probiotics to atone for an unhealthy lifestyle," says Dr. Bulsiewicz. "The first step toward gut health should always be to optimize your diet by consuming a diet that maximizes a diversity of fresh fruits and vegetables." (Heads up: Here are some new ways to add more probiotics to your diet.)
In the end, though, there's a pretty strong argument for giving probiotics a try if you haven't already. "There is no known risk, and there is a potential benefit at an inexpensive dollar cost," says Dr. Roizen. In other words, probiotics almost certainly won't do you harm, and there's a decent chance they'll help. So why not give them a try?