I learned that my indoor environment could be bad for me. My sister and mom's perfume is not healthy for me to breathe. I can get second hand smoke from my neighbors because when the window is open. My cats litter could also effect me because they kick dust in the air.
Cook the food safely and cleanly. You have to make sure everything that you cook is not toxic to you because it's old. If you warm up frozen food in the microwave it could make you sick. It's not healthy for the food to go from super cold to super hot. You shouldn't use the same cutting board for all your food.
You do all of this to not get sick or hurt and end in the hospital. I learned that if I am overweight that it will effect my breathing, my digestives system, maybe cause diabetes and other health problems. You need to eat a certain amount of calories per day in order to have energy. You need to get enough sleep so your body can work right.