Probiotics are good bacteria that are found in food or supplements. Probiotics are defined as
“Live microorganisms that, when administered in adequate amounts, confer a health benefit on the host.” (WHO/FAO, 2002)
For a probiotic to qualify as a true probiotic, any health benefits must be proven by clinical trials. In addition, a probiotic product must contain the same strain(s) and dose used in clinical trials.
It wasn’t so long ago that all bacteria were thought to be bad since the first bacteria we were able to identify were pathogens that caused illnesses and infections. Today, we know that most bacteria are either completely harmless or even vital to our health.
Bacteria are classified according to their genus, species and strains. There are different strains of bacteria with different genetic compositions, resulting in different characteristics. Biological strains are populations of bacteria that descend from a single individual or pure culture. Bacteria of the same strain have certain characteristics that differentiate them from bacteria of other strains.
Bacteria are classified into genus, species and strains. Different strains of bacteria have different genetic composition resulting in different characteristics.
In the past decade, research on bacteria and their significance to our health has boomed, becoming one of the hottest research areas. At BioGaia, we have been researching Lactobacillus reuteri for more than 30 years.
Different probiotic products contain different probiotic strains. As a result, a probiotic product containing Lactobacillus reuteri (for example, L. reuteri NCIMB 30242) is not equal to another probiotic product containing another strain of Lactobacillus reuteri (for example, L. reuteri DSM 17938).
It is for this reason that bacteria must be defined and tested at the strain level in clinical trials.
We need to clarify which strain we mean when we talk about lactic acid bacteria. The fact that a product contains “lactic acid bacteria” or “Lactobacillus reuteri” is not enough. Species and strain names are needed to know what probiotic we are talking about and the benefits we can expect from it, for example, Lactobacillus reuteri DSM 17938. Furthermore, clinical trials must be conducted at the strain level in order to define a probiotic bacteria.