Main Menu and Other GUI Help

I have system in my game that gives the player Hunger and Thirst, Seen Below

And I have a main menu, Seen Below

The problem here is that the Hunger and Thirst go down even when the player is in the menu. How would I make the GUI work only after they select PLAY?

You could have 2 bool values inside a player. One could be for when the player is in the menu, and one for when the player is playing. Tick the values according to where the player is. When doing the stats script, before updating the value of the stat, check if the value that shows that a player is not in a menu is true and only after that set the stats.