From aiding in digestion to bolstering the immune system, naturally occurring, so-called "friendly" bacteria which populate the body's intestines are critical for good health, says Sean Farmer. According to Sean, chief scientific officer of Ganeden Biotech, probiotics—dietary supplements containing friendly bacteria—may offer countless additional health benefits by replenishing the body's natural gut flora and maintaining a healthy balance of good bacteria. Dr. Oz talks with Sean about the history of probiotics and the role they play today in a healthy diet, as well as their many applications in industries such as farming and medicine.

Sean also talks about the risks and consequences of killing bacteria that are beneficial to the body's health through things like antimicrobial soaps and antibiotics, while permitting resilient, harmful bacteria strains to propagate. "We have to really take a look at, 'Is our cultural practice of killing bacteria really helping our health or are they really making tougher bugs to fight down the road?'" Sean says.