There are many causes of body edema, common causes include malnutrition edema, cardiogenic edema, nephrogenic edema, etc. It is recommended to confirm the diagnosis under the guidance of a doctor and actively accept the treatment. 1. Malnutritional edema: this kind of edema is mostly due to long-term nutritional deficiency or protein loss, which causes the decrease of plasma proteins leading to the decrease of limb osmotic pressure, and generalized edema will appear. 2. cardiogenic edema: general right heart failure will lead to cardiogenic edema, cardiac blood loss will lead to fluid retention, and then body edema, mostly manifested as lower extremity edema. 3. Nephrogenic edema: it is a common clinical cause of edema. Kidney disease leads to a decrease in water and sodium excretion from body fluids, which will lead to different degrees of edema in the lax part of the tissue. Malnutrition, heart failure, kidney disease can lead to edema, it is recommended to confirm the diagnosis under the guidance of a doctor and actively accept the treatment.