First， leftovers of rice are ok， butvegetables leftovers are not suggested. Vegetables， more or less， will produce materials like the "nitrite" in the process of storage， which is harmful to our health. Second， prepare professional food preservation boxes to preserve leftovers. In comparison with bowls and plates， they can better preserve food and avoid food-contaminated substances. Third， the leftovers need to be heated thoroughly to avoid hidden dangers. It is recommended that you add some fresh vegetables， such as tomatoes， onions and lettucewhen you are heating the food. In addition， you can add some vinegar to the hot dishes to supplement the nutrition and to add flavor. Fourth， “cook within ones appetite” and eat the food right after cooking. We should avoid leftovers at home as far as possibleto avoid a lot of unnecessary troubles.

（Responder： Silu WANG， vice president of the Nutrition Health Promotion Association of Inner Mongolia，Director of the Capital Health Nutrition and Food Society）