Ever try to read a yogurt label out loud? With about a million cultures ending in “ophilus” and “erium,” it can sound like a Greek army ready to attack. But rest assured, there’s no need to take cover. These microorganisms are a completely friendly bunch, with a variety of potential health benefits to the immune system and digestive tract. The only challenge: separating the real deal probiotics from the duds.

The Strain Game: What It Is

While not all research has been conclusive, one study showed that employees given probiotics missed fewer days from work due to respiratory or gastrointestinal illness than those who didn’tIncreasing+work-place+healthiness+with+the+probiotic+Lactobacillus+reuteri:+A+randomised,+double-blind+placebo-controlled+study.+Tubelius,+P.,+Stan,+V.,+Zachrisson,+A.+Tetra+Pak+Occupational+Health+and+Safety+AB,+Ruben+Rausings+Gata,+Lund,+Sweden.+Environmental+Health+November+7+2005;+4:25. Not the worst way to save up some extra personal days.Available as supplements or in foods like yogurt, kefir, miso, tempeh, and a few new juices and soy drinks, probiotics are live microorganisms (usually bacteria), similar to the “good bacteria” found in the human gastrointestinal tract. They produce enzymes that break down food and nutrients and are essential in fighting harmful viruses and bacteria that can cause some pretty uncomfortable scenarios like irritable bowel syndrome, yeast infections, and urinary tract infections (oh my!). Probiotics are sometimes prescribed to offset the side effects of antibiotics, which tend to kill the good bacteria along with the bad, resulting in cramping, diarrhea, and other fun times.

Probiotic Primer: What It Means To You

Before popping any old probiotics, it’s important to read the fine print. Check the product label for “live and active cultures,” particularly lactobacillus, the most effective bacteria for breaking down food, absorbing nutrients, and fending off “unfriendly” organisms. Bifobacterium probiotics are also touted for similar effects.

Also, look out for products that list the full names of their probiotics, since companies are eager to spotlight the strains with research to back up their benefits. Stonyfield Farm’s yogurt, for example, lists “Lactobacillus rhamnosus HN001” on its label, signifying the genus: Lactobacillus, species: Rhamnosus, and strain: HN001. For more targeted benefits (i.e. fighting digestive problems vs. a common cold) a doctor can help recommend a specific strand that’s most effective. Just note: children, the elderly, and people with compromised immune systems should consult with a healthcare professional before taking probiotics, as some mild digestive side effects have been reported.

One final tip: keep ‘em cool. Research shows that the number of living bacteria in probiotic yogurt decreases in room temperature. Supplements should also be stashed in the fridge for optimal benefits.

Photo by Jordan Shakeshaft