Natural nutrition for a strong immune system, a healthy gastrointestinal tract, and more! Swanson Lactoferrin is a natural protein found in milk that has a wide range of nutritive benefits throughout the body. Best known as an iron-binding protein, lactoferrin plays an important role in the immune system and also promotes the growth of beneficial bacteria in the intestinal tract, which can enhance both immune and gastrointestinal system function. Our High Potency Lactoferrin capsules deliver a powerful 100 mg of all-natural, dairy-source lactoferrin to strengthen your body's defenses.