Yes, you have to dramatically change your diet to get rid of the yeast. It is not necessarily a life sentence, but you may need to limit certain foods once you get well, or your symptoms could manifest again. I know for me, I need to limit my sugar and grain intake, and absolutely no yeast. The only way to know for sure is to experiment with an antifungal diet. Tests may not be conclusive. They weren't for me, anyway, but on my own I finally figured it out. Candida is a culprit with many gut problems, but there are other types of fungus that can affect you, as well. Grains, including corn, and peanuts are commonly contaminated with aflatoxin B1, a carcinogenic Aspergillus fungal by-product. You may want to take natural antifungals if you decide to follow the diet, as well. Did your friend tell you that you may feel worse before feeling better once you begin? That is a good indication that you do have a yeast problem, because the toxins are dying off and leaving your body. You may feel miserable for a few days. Good luck with what you find out!