The red blood cell volume distribution width (RDW) is obtained by measurement with a hematocrit analyzer and is a parameter that reflects the heterogeneity of the peripheral blood red blood cell volume. What it expresses is the degree of homogeneity of red blood cell volume size. If the red blood cell volume size is homogeneous and consistent, the parameter is lower and within the reference range. If the erythrocyte volume size is inconsistent and varies widely, the parameter is higher than the reference value. The morphological characteristics of erythrocytes are different in anemia caused by different etiologies. RDW can be used for early diagnosis and efficacy observation of iron deficiency anemia; RDW/MCV combination is also used for morphological classification of anemia, etc. How to prevent high red blood cell distribution width? 1. Dietary regimen The diet should be reasonable, the food must be diversified and the recipes should be broad, and there should be no partial diet, otherwise it will cause anemia due to the lack of certain nutrients. It should be nutritious and easy to digest. Diet should be regular and controlled, and overeating is strictly prohibited. Eat more iron-rich foods, such as pig liver, pig blood, lean meat, dairy products, beans, rice, apples, green leafy vegetables, etc. Drinking more tea can supplement folic acid and vitamin B12, which is beneficial to the treatment of megaloblastic anemia. However, tea is not suitable for iron deficiency anemia because it is not conducive to the absorption of iron in the body. Appropriate supplementation of acidic food is beneficial to the absorption of iron. Avoid eating spicy, cold and indigestible food. Usually can be combined with nourishing dietary therapy to nourish the body. 2, the combination of work and rest to carry out appropriate physical activity.