Since there is soy added to so many processed foods, I've decided not to add any additional soy to my diet. Check out the labels on the foods in your home, and you'll find that you are already consuming soy products almost daily.
If you research online, you will find many articles that say soy can eventually cause problems with a healthy thyroid, and many that say it doesn't. I think you have to read a lot and make your own decision.