White sugar is refined sugar made from molasses squeezed from sugarcane and sugar beet. White sugar is white, clean and high in sweetness. Sugar is easily contaminated by pathogenic microorganisms in the process of production, packaging, transportation and storage. In particular, sugar that turns yellow after being stored for more than one year is often polluted by mites. According to the experiment, 1.5 million mites were detected from 500 grams of white sugar. If people eat white sugar contaminated by mites, mites will enter the digestive tract to parasitize, causing abdominal pain, diarrhea and other symptoms, and some even cause allergic reactions. If this contaminated raw sugar is directly added to the food of infants or the elderly, mites can enter the lungs due to coughing and cause asthma or hemoptysis, and it is easy to be complicated with tracheitis or pneumonia.