Cast-iron cookware to increase iron intake?

I've read that you should cure cast-iron cookware to take care of it properly. But I am buying a cast-iron pan specifically so I can heat tomato sauce in it to increase my iron intake. Since curing reduces the amount of iron that ends up in food, should I just wash my iron pan completely with soap, as I would with any other pan? This won't hurt the pan, will it? What is the point of curing iron pans anyway?