By Nutrition Expert – Trupti Gurav,Mumbai
Reheating food is one of the most common processes in our day to day life as most of us are used to working for long hours and usually we do not have time to cook. Although the reheated foods save time and energy which is the most valuable commodity these days but it raises a question as foods that we reheat, is it safe to eat anymore?
The State Sanitary Code now requires that the entire mass of all cooked and refrigerated potentially hazardous food which is to be reheated must be reheated to 165° F or above within two hours.
Foods may be prepared as close to the serving time as possible, and in quantities that will minimize leftovers, thus eliminating any need for reheating.
Whatever be the case, experts feel that one should avoid reheating food because the chemical change in food due to reheating often leads to food poisoning and food-borne diseases.
How Many Times Can You Reheat Food Safely?
Ideally, we should all eat food straight after it has been cooked. This is when it’s at its freshest and likely to taste the best.
In terms of food safety, however, so long as you reheat the food at the correct temperature and for the correct duration of time, it can in fact be safely reheated multiple times. However, the Food Standards Agency (FSA) recommends that food is only reheated once.
Be aware that when you do reheat food, each time the quality of it will decrease. This unfortunately means the consistency or even taste won’t be as good as the first serving. 
Why should you avoid reheating food? 
Reheating can turn healthy food to harmful food. Reheating food can destroy the nutrients in the food and cause food poisoning and food-borne diseases.
Leafy greens: Green leafy vegetables like spinach are rich in iron and nitrates and when reheated these nitrates can turn into nitrites and your food may thus develop carcinogenic elements and cause food poisoning. Reheating green leafy vegetables also destroy the nutrients.
Chicken: When chicken is cooked for the first time and refrigerated, its protein composition changes on heating for the second time. The negative reaction between proteins when reheated may lead to digestive disorders. If you reheat it, some safety measures should be kept in mind. It should not be left out of the fridge in a raw state.
Rice: Rice contains spores of a bacterium and they survive even after the rice is cooked. When left out at room temperature these spores grow into bacteria and when reheated they become toxic that may cause vomiting and diarrhoea. Rice should be served as soon as it has been cooked.
Milk and cream: Several changes take place in milk on cooking because of the action of heat on the milk proteins. Some acids are produced which are not good for health.
Mushroom: Mushrooms contain proteins that can be damaged by enzymes and bacteria if not stored properly, e.g. left at room temperature too long. Reheating and consuming mushrooms that have deteriorated in this way can give you a stomach ache.
Boiled or fried eggs: Reheating eggs can make them toxic causing digestive tract troubles. The protein in eggs gets destroyed when they’re repeatedly exposed to heat.
Potato: Store cooked potatoes in refrigerator as soon as they are cooked if not eaten immediately. Potatoes lose their nutritional value if they’re left to sit at room temperature for a long time. It is a storage issue more than reheating.
Oil: Cooking oil can turn into dangerous trans-fats if overheated. Also, walnut oil, avocado oil, grape seed and hazelnut oil have very low smoke points. They can become rancid on reheating. In addition to having strange flavours and odours, rancid oil may possibly contain carcinogenic free radicals.
It is suggested to cook food in limited quantity so that there is no leftover. In case, you are left with some extra food, either consume it without reheating or give it to the needy. Make sure that the leftover is kept in a closed container or in a refrigerator.