There is always candida in the gut. The question is whether it is under control, or if is overgrowing and crowding out healthy bacteria. Diet and the strength of the immune system are what is key. If also seems impossible to completely avoid all parasite exposure, however with a strong immune system they will not be able to cause infection. Eating a diet that contains herbs such as garlic, turmeric, cayenne pepper, black pepper, ginger, etc. will also help avoid parasite infection and candida overgrowth.