As a Duke University Hospital dietetic intern who also happens to be lactose intolerant, Lauren Littmann is in the unique position of really needing to know her stuff when it comes to lactose-free options. So when she recently tweeted at us, “My favorite source of probiotics. Fermented milk, y’all #happygut” alongside a pic of our blueberry kefir, we knew that we wanted to reach out to her and hear what else she had to say.