One overlooked mechanism that supports your innate immunity is gut health, specifically the role probiotics play. Good probiotics benefit your health by keeping your gut microbiota, inflammation, and immune system balanced preventively, as well as acutely when you are sick, so that no matter which flu strain comes along, your immune system is ready.

If you’re most interested in taking a probiotic supplement for overall gut health, I suggest starting with 30 to 50 billion CFUs. Take probiotics on an empty stomach once or twice a day for at least three months. After that time, reassess and decide if the benefits warrant continuing a maintenance dose of the probiotic supplement. However, if you have SIBO, beware of starting a probiotic too soon after your treatment. In this case, it’s best to work with a health practitioner on which probiotic is right for each stage of the treatment.


In the past five years, for example, several combined analyses of dozens of studies have concluded that probiotics may help prevent some common side effects of treatment with antibiotics. Whenever physicians prescribe these medications, they know they stand a good chance of annihilating entire communities of beneficial bacteria in the intestine, along with whatever problem-causing microbes they are trying to dispel. Normally the body just needs to grab a few bacteria from the environment to reestablish a healthy microbiome. But sometimes the emptied niches get filled up with harmful bacteria that secrete toxins, causing inflammation in the intestine and triggering diarrhea. Adding yogurt or other probiotics—especially the kinds that contain Lactobacillus—during and after a course of antibiotics seems to decrease the chances of subsequently developing these opportunistic infections.

Renew Life offers a powerful, high potency blend of 10 specially selected Lactobacillus and Bifidobacterium strains designed to help restore your body’s good, natural ora. Their probiotics come in a special capsule designed to survive stomach acid and make it intact into the intestines to deliver the probiotics more effectively where they are most needed.


Coming in at a close second, our runner-up as the best probiotic for women is the Culturelle Women’s Healthy Balance Probiotic. As the #1 recommended brand by pharmacists, it is easy to see why so many women are turning to Culturelle for their digestive health. Featuring the LGG culture and a laundry list of other healthy bacteria, this probiotic offers a wonderful balance between digestive and feminine health. The Culturelle Women’s Healthy Balance Probiotic is also taken in an easy, chewable tablet and can even be taken during pregnancy, making it one of the most versatile formulas we reviewed!
Yogurt: It can contain Streptococcus thermophilus, Lactobacillus bulgaricus, L. acidophilus, and Bifidobacterium bifidum. Research has shown links with yogurt to have positive effects on the gut microbiota and is associated with a reduced risk for gastrointestinal disease and improvement of lactose intolerance (especially among children), type 2 diabetes, cardiovascular disease, allergies and respiratory diseases, as well as improved dental and bone health.
Quick note about some formulations with multiple strains (including this one): Take a look at the label below and you’ll see that the supplement contains a mix of strains, but the label just says there is a total of 20 billion CFUs (how they measure the amount of bacteria). This does not tell us how much of each particular strain there is, and we want to know that there are at least 1 billion CFUs per strain to get a beneficial effect.

Unfortunately, the U.S. has no federal standards for probiotic supplements. Therefore, you run the risk of purchasing a product without any guarantee that it contains its advertised probiotic strains, that the strains are alive, or that the product is free from unhealthy ingredients. Therefore, it may be best to choose a brand-name probiotic that has research backing their effectiveness. Here are some examples:
Using probiotics benefits and balances immune function, influences hormone levels, aids in digestion and nutrient absorption, produces some vitamins, and balances blood sugar insulin responses. By preventing and reducing leaky gut and controlling levels of pathogens, probiotics reduce harmful bacterial by-products that can enter the brain and contribute to brain fog.

To factor strain-specific benefits into our efficacy score, we referenced the information in these guides. Products were rewarded for containing strains on these lists. Additionally, measured levels of each strain were compared to what is thought to be effective based on these guides, and scores were scaled accordingly. In cases where products did not list strain-specific amounts, or their listed strains were not included in these guides, total measured CFUs were compared to a general effectiveness threshold of 1 billion CFUs cited by research published in the American Journal of Clinical Nutrition11.

​​​​​​AZO Complete Feminine BalanceTM is a daily probiotic supplement designed for the unique needs of women. Researchers that formulated the blend started by selecting species that are dominant in the healthy vaginal microbiota. Then they further refined the formula by selecting strains of probiotics that flourish in the vagina. The blend is clinically proven to help protect vaginal/feminine health.*
Notably, after someone was tagged a “persister” or “resister” clear patterns emerged on how probiotics would impact his or her indigenous microbiome and gut bacteria profile. "Although all of our probiotic-consuming volunteers showed probiotics in their stool, only some of them showed them in their gut, which is where they need to be," Eran Segal said in a statement. "If some people resist and only some people permit them, the benefits of the standard probiotics we all take can't be as universal as we once thought. These results highlight the role of the gut microbiome in driving very specific clinical differences between people."
"People have thrown a lot of support to probiotics, even though the literature underlying our understanding of them is very controversial; we wanted to determine whether probiotics such as the ones you buy in the supermarket do colonize the gastrointestinal tract like they're supposed to, and then whether these probiotics are having any impact on the human host," says senior author Eran Elinav, an immunologist at the Weizmann Institute of Science in Israel. "Surprisingly, we saw that many healthy volunteers were actually resistant in that the probiotics couldn't colonize their GI tracts. This suggests that probiotics should not be universally given as a 'one-size-fits-all' supplement. Instead, they could be tailored to the needs of each individual."

Immunity and colds/flu.There’s a close connection between the bacteria in your colon and the immune system. Several studies, including one in 2012 in the British Journal of Nutrition, have found that certain probiotic strains boost measures of immune response—but whether this translates into any clinical benefits is uncertain. Studies have been inconsistent, for example, as to whether probiotics will actually curb colds and other upper respiratory infections. In 2014 a review in the British Journal of Nutrition, which looked at 20 clinical trials, linked probiotics to shorter duration of colds, but not necessarily reduced incidence or severity. Similarly, a 2015 Cochrane review of 12 clinical trials concluded that certain probiotics may help prevent or shorten such infections, though the quality of the studies was poor.
Probiotics are “friendly” bacteria that inhabit your body. Sound strange? These microscopic roommates can be your best buds if you show them a little love. One surefire way to do that is with probiotic supplements. Probiotics support the right ratio of good to bad bacteria in your gut. For bonus points, call on digestive enzymes. These unique blends offer specific nutritional support to assist digestion and nutrient absorption. Your healthy body will quickly appreciate these lifelong friends.
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