The clinically studied probiotic concept Probi Defendum® is a combination of the strains Lactobacillus plantarum HEAL9 and Lactobacillus paracasei 8700:2. The efficacy and safety of Probi Defendum® have been investigated in multiple state-of-the-art clinical studies, with more than 1700 healthy people in total. The effects on the immune system have been studied in both adult populations and in children. The focus of the studies has been on outcomes related to respiratory health. Dietary supplements containing probiotics are thought to help maintain a healthy microbiota as we age.