THE PROBIOTIC BRAND DOCTORS RECOMMEND MOST. Recommended by Gastroenterologists two times more than any other probiotic brand, Align is the #1 doctor and gastroenterologist recommended probiotic brand. When taken daily, Align Probiotic Gut Health + Immune Support capsules help support a healthy digestive system and help strengthen your immune system.* Align Probiotic Gut Health + Immune Support capsules are vegetarian, gluten-free, and do not require refrigeration.Among Doctors and Gastroenterologists who recommended a brand of probiotic in ProVoice 2023 survey.