So I run a probiotics site...and what that marketing claim means is that that precise strain of Lactobacillus Rhamnosus is the most researched.<p>There are many more studies on the species of probiotic Lactobacillus Rhamnosus as a whole...but for that exact &quot;cousin&quot; of the species, it is likely the most clinically researched probiotic.<p>There&#x27;s a bit more info on it here: <a href="http:&#x2F;&#x2F;probiotics.org&#x2F;lactobacillus-gg-benefits&#x2F;" rel="nofollow">http:&#x2F;&#x2F;probiotics.org&#x2F;lactobacillus-gg-benefits&#x2F;</a>