I've eaten that, too! After eating a box, I felt weak during that time. I lost 5 pounds in the first two weeks, and then it didn't work. Now all fat, fatter than before eating! It will bounce back!
But I also have friends who eat effectively. It varies from person to person anyway!
I suggest you try it first. If you think everything is good, congratulations! If you don't feel good, stop at once. After all, there is only one body!