It deserves you right to gain weight.

请问老师 "It" 在这里作形式主语吗？那真正的主语是哪个？"to gain weight"?

To gain weight deserves you right? 总感觉不太对。不该是sb deserve sth吗？

"It deserves you right to gain weight." 和 "You deserve to gain weight. " 

有什么区别吗？谢谢！