Yes. When creating a meal, under "guests" you can click a box labeled
"I would like to approve guests before they can join my meal."
If you click this box, you will be notified each time a guest wants to join your meal. You can decide whether to approve or decline each guest. Guests will not see your meal details (like address) until you approve them.
To approve/decline them, you go to your guest list and click either "accept" or "decline"
If you do not choose this option, guests can instantly join your meal with no need for your approval.