Most of people, (including the author) are usually warm the food for two or three time although those are leftovers, especially our favorite foods. Some of food are safe for warm and some of food are dangerous to re warm. Below those (7) foods should not re warm.
People should not heat up the Spinach again and again because the spinach has Nitrates, those Nitrates is cause for the cancer when it was heat up again and again.
When we cook for the soup and vegetable fried, we usually Chinese celery for good smell. Its smell with great smell in especially in chicken soup and pork soup. In this Chinese celery belongs the Nitrates like the spinach, so people should drink the soup and avoid the heat up again and again.
In the carrot has also the Nitrates and if people heat up again and again, it make the dangerous and destroy for the body that why people should eat the carrot by juice or salad.
The potato has too many notorious for the people but if you did not eat within a day after cooking, you will lost this health benefit and if you heat up again on next day, it make the dangerous for the people and we suggest that you should boil or salad or Puri (Indian food)
The heat up again for the boiled eggs, fried eggs are very dangerous for the people because its smell and its taste changes and the compound are change from the benefits for people to the dangerous for the people.
The chicken has dangerous for the people after a day, it makes the problem for the digestive system. Some people, include the author, usually heat up the chicken curry after the next day. Because the chicken has wealth in protein and the structure of the protein usually change the next day. The chicken or the red meat has wealth in protein and it is be worried for the fact. You should eat the chicken curry or other chicken fired or something like that, you should eat while it was cool. If you need to warm up, you should warm with low temperature with long time.
The re warm mushroom has the high dangerous for the people. So, people should eat within these mushrooms in cooking day. Otherwise, you should eat with cool. The re warm mushroom make the digestive system and a chance for the heart problem.
Above those foods are should not re warm or heat up again and again after cooking day or cooking time.