Probiotics

++Iowa State University sponsors "Current Issues in Nutrition" webinars Here is my summary of the most recent one. The speakers were Mary Ellen Sanders and Suzanne Hendrich, two respected researchers on this topic.

Probiotics are microorganism that a person might get in food, which may be eaten help the digestive system work better. The scientific definition of a probiotic has 3 parts: 1)living cells, that 2)provide health benefits to an individual 3)when administered in a large-enough dose. There is no legal definition. Therefore, food companies can say what they want to about their artificial baby milk (formula), or yogurt (or kefir), or other products supposedly containing probiotics, even if they don’t match the scientific definition. This may be misleading, but it is not illegal.

Probiotics also have some other characteristics that are being studied by researchers. One is that their activity is species-specific, and usually strain-specific. In other words, one kind of lactobacillus does not function like another, much as some dogs were bred to be hunters and some as herders. Lactobacillus is as different from bifidus as a dog is from a cat or a horse. Another characteristic is that “host flora” affects how well the probiotics benefit the host. In other words, each person has millions of bacteria living inside him/her (mostly useful ones), but the exact kinds and amounts are as specific to each person as finger prints. These exact groupings affect how well the probiotics work to protect the person’s health, or even whether they live long enough to work. There is a lot of interest among researchers on how much help a person can get from probiotics, and on how big a dose a person needs to get any help.

A related topic is prebiotics. You can think of prebiotics as food for probiotics. Dr. Hendrich is doing research on fermentable, non-digestible carbohydrates (a category of dietary fiber) as prebiotics.

A lot of work still has to be done before we can make specific recommendations on what to eat, and how much, in order to get the health benefits of probiotics; but it is always a good idea to eat a varied, balanced diet – and foods like yogurt definitely can be a part of that.