Low creatinine in children is mainly related to physiological reasons, malnutrition, anemia and so on. 1. Physiological reasons: because creatinine is mainly located in muscle tissue, children’s muscle content is small, and more fat tissue, so creatinine will appear physiological decrease, with the age of growth, and gradually return to normal. 2. Malnutrition: too little nutrient intake, children intake of fish, shrimp, eggs and other proteins is too little, the body utilization rate is reduced, the body wasting, resulting in low creatinine levels. You can increase high-quality protein diet, such as lean meat, beef, soy products. To improve the situation of low creatinine. 3. Anemia: Malnutrition in children due to picky eating or improper feeding can lead to iron deficiency anemia or megaloblastic anemia, thus causing low creatinine. Creatinine is a product of human muscle metabolism, if creatinine is persistently low, we should consult a doctor in time for symptomatic treatment. Under the guidance of the doctor to choose the appropriate treatment.