The refined oil which you buy from market is very dangerous for your health because there are lots of chemical which are added in it. Best is to make it at home. Doctors and advertisements are also big cheaters who suggest you to eat refined oil because all are interested to earn the money. But we are very careful about your health. You can make refined oil from mustard oil. You first buy mustard from market. You can make its oil from your local market. Then you can convert it in refined oil by heating it from 10 to 15 minutes. Now, it will become testy refined oil. It will be useful for heart patient and for joint pain patients.