Reheating foods can be really handy especially if you work in an office environment. However not all foods respond very well to reheating either because of how they react with bacteria while they are stored, or because of proteins that are broken down during cooking.
It is important to bear in mind that the following foods are accredited by the Food Standards Agency as to be avoided for reheating purposes.
-Rice- I'm probably the culprit when it comes to reheating Rice; you cannot be a true African if you do not reheat that bowl of Jollof rice that has been sitting pretty in the fridge/freezer for days. Believe it or not, if you have been reheating rice, STOP it right now. The bacteria which can grow readily on rice does not always die on re-heating. How cooked rice is stored is more important than the actual reheating itself, according to (The Food Standards Agency).
-Chicken- Chicken and Poultry in general have an amount of salmonella contamination. Reheating chicken in a microwave particularly becomes a problem as some parts of the food cook faster than others. It is very vital to turn the chicken frequently to ensure even heating inside and out.
-Leafy Veggies & Spinach- When Spinach is reheated, it can cause "Blue Baby Syndrome". Spinach & other leafy vegetables contain a very high concentration of nitrate which is harmless, however it can be converted to nitrites and then nitrosamines which are known to affect the bloodstream's ability to carry oxygen and in young children can cause "Baby Blue Syndrome"
So if you have been reheating any of the above, I suggest you stop now :-)