Indeed, at the beginning of the fast, the odor is worse, and as soon the inner cleaning of the body is done, the odor should improve, the tongue is cleaner, the breath is fresher, the skin lighter, but for some day during fasting, it's the opposite. The more you need the cleaning, the worse your odor is. There's very good bookq about how to clean the body, by Herbert Shelton , they are old books.