Dont reuse cooking oil
This is a horrible practice. It might save money in the short run, but will cost a lot more in hospital bills later on in life.
When we heat oil, it oxidizes and produces free radicals. Reusing oil multiple times increases the number of free radicals and makes the oil more toxic.
Moreover, when we reuse cooking oil for deep frying, food particles left over from the prior use break down further with each subsequent use. This produces acrylamide, which is a carcinogenic compound.
On top of all that, reused oils also produces other harmful compounds like polar compounds and trans fats. Trans fats form when unsaturated fats are exposed to high heat during deep frying. more