At an integrative pharmacy in the Upper Midwest, the Natural Foods Merchandiser Secret Shopper asked:

Are probiotic drinks a decent replacement for probiotic pills?

Store: That really depends on which drink and which pills you’re considering. I’m pretty sure some beverages have far fewer organisms than most pills, but you’d have to look at the labels and compare them.

NFM: Does the mode of delivery—drinking them in a liquid—affect the probiotics’ efficacy?

Store: I don’t think so, but I’m not entirely sure. But you do want to be careful not to buy a drink with lots of sugar.

NFM: Because sugar interferes with the probiotics or just because I should always avoid excess sugar?

Store: I don’t know that sugar interferes, per se, but if you’re drinking the beverage because you have a yeast infection, for instance, then extra sugar wouldn’t be good. And yes, you also want to be mindful of sugar intake overall.

How did this retailer do?

Our expert educator: Amy Burkhart, MD, an integrative physician and registered dietitian in Napa, California

This retailer did pretty well. Most probiotic beverages have a fairly low number of beneficial bacteria in comparison to probiotic pills, but it really varies by product. However, some beverages do not have any actual number of organisms listed on the label, so a comparison cannot be made. The number of viable beneficial bacteria in either a pill or beverage will also depend on the age of the product, transportation and storage methods. In truth, it is very difficult to know the actual number of “alive” bacteria in a product unless it has been tested by a third party such as ConsumerLab.com.

The mode of delivery does matter for probiotics, as some bacteria cannot survive passage through the stomach because of the acid that is present there. However, most Lactobacillus, Bifidobacterium and Streptococcus species are resilient and can survive. These are the most common type of bacteria added to probiotic beverages.

Finally, sugar does not interfere with probiotics, but I do agree that extra sugar is not beneficial for anyone.