Most of us don't have a lot of extra time to check every health claim listed on every product label in the grocery store. And even if we did, we probably wouldn't have access to, say, a bioinformatics lab to help us fact-check.
In general, all we can do is trust the label and hope no one's lying to us, right? Unfortunately, that's not always the case. Bad news for kefir drinkers—new research suggests that most brands of the drink seriously overstate the beverage's gut health benefits.
A study from researchers at the University of Illinois and The Ohio State University looked at probiotic health claims on the labels of kefir products from five major brands.
"The products sampled had 2 primary issues," the study's corresponding author, Kelly Swanson, PhD, The Kraft Heinz Company Endowed Professor in Human Nutrition at the University of Illinois at Urbana-Champaign, told Eat This, Not That! in an interview. "First, the bacterial counts measured were much lower than those listed on the label. Second, the bacterial species measured did not accurately match those listed on the label."
He added that, while some of the bacteria that kefir products claimed to include were not actually present in the beverages, other bacteria that the products didn't mention showed up in their analysis. In short, it's possible that some kefir brands you'd find at your local grocery are overstating the number of helpful bacteria they contain and instead, are misrepresenting the actual cultures that exist inside.
"It is unclear to us why this contradiction exists," Kelly added. "We think that companies manufacturing such products need to have a higher level of accuracy."
Still, Kelly noted that, given that the study only looked at five of the brands on the market, the results might not necessarily be applicable to all brands. Alternatively, if your faith is in kefir is shaken, you could shift your allegiance to another dairy product to get your fix of good bacteria.
"Traditional buttermilk and cottage cheese with live cultures can also be a good source of probiotics and help with gut health," says Vandana Sheth, RDN, CDCES, FAND.
For more on how labels could be misleading you, be sure to check out these 6 Popular Supplements That Don't Actually Work, According to Experts.