While one 2009 study did show some evidence for reducing cold and flu symptoms in children ages three to five and a 2015 analysis showed probiotics to be better than placebo in preventing acute upper respiratory infections, neither were enough to convince the National Institutes of Health of the efficacy of probiotics for colds and flu. The NIH confirms, “the evidence is weak and the results have limitations.”
There are two main types of probiotics; the first is the live cultures I describe above, like the strains of Lactobacillus and Bifidobacterium. You might have heard some naysaying about this kind of probiotic—the typical argument against them is that the classic form of live cultures is destroyed by the acidic environment in the stomach. To get around this, quality probiotics are made with an acid-resistant capsule so that they don’t get immediately broken down. (Which means you don’t have to take the probiotics with food, although I normally do. I’ll sometimes break the capsule and mix it into a smoothie, or use the powder form. You might lose a bit of potency but it’s not significant.)
Walk into any grocery store, and you will likely find more than a few “probiotic” products brimming with so-called beneficial bacteria that are supposed to treat everything from constipation to obesity to depression. In addition to foods traditionally prepared with live bacterial cultures (such as yogurt and other fermented dairy products), consumers can now purchase probiotic capsules and pills, fruit juices, cereals, sausages, cookies, candy, granola bars and pet food. Indeed, the popularity of probiotics has grown so much in recent years that manufacturers have even added the microorganisms to cosmetics and mattresses.
Probiotics have direct and indirect effects on your immune system. They can help tip an imbalance in an immune response, such as in seasonal allergies, to a more balanced state. Probiotics benefits have direct and indirect effects on your nervous and endocrine systems, too, and are part of your enteric nervous system. They can influence every system in your body. The amount of probiotic pills and supplements shown to be beneficial in research for various conditions differs based on the population and condition studied, so no blanket recommendations can be made.
Uncontrolled changes in blood sugar levels or a decreased ability to regulate insulin can have serious effects on your overall health, and since far more men than women are at risk for these changes, these issues are well worth paying attention to.5 Research indicates that regularly taking probiotic supplements containing Lactobacillus and Bifidobacterium can help your body maintain blood sugar levels already within a normal range, whether you're simply at risk for insulin-related challenges or you're already experiencing them.
Better Health Review ranks Ultimate Flora as the most effective probiotic supplement. It contains 30 billion active bifidobacteria for colon health, and 20 billion lactobacilli and lactococcus cultures for the small intestine. According to Better Health Review, it contains all natural ingredients. It earns a perfect 5 score from Better Health Review, and the magazine “Vitamin Retailer” voted it best two years in a row.