GUI.Lable slowdown problem

Hi guys, I'm trying to make an inventory menu where behind the object there is their respective names, this is the code I used in the OnGui() function:

 if(iMode)
     {
         //Mostra i nomi degli oggetti
         var div = gridPosition * 2;
         if(div < currentInventoryObjects.length)
         GUI.Label(Rect(startPos+100,startPos+25,iconSize+100,90), currentInventoryObjects[div].name + ".obj", customGUIStyle2);
         if(div +1 < currentInventoryObjects.length)
         GUI.Label(Rect(startPos+100,startPos+iconSize+60,iconSize+100,90), currentInventoryObjects[div+1].name + ".obj", customGUIStyle2);
         if(div +2< currentInventoryObjects.length)
         GUI.Label(Rect(startPos+iconSize+185,startPos+25,iconSize+100,90), currentInventoryObjects[div+2].name + ".obj", customGUIStyle2);
         if(div+3 < currentInventoryObjects.length)
         GUI.Label(Rect(startPos+iconSize+185,startPos+iconSize+60,iconSize+100,90), currentInventoryObjects[div+3].name + ".obj", customGUIStyle2);
         if(div+4 < currentInventoryObjects.length)
         GUI.Label(Rect(startPos+2*iconSize+255,startPos+25,iconSize+100,90), currentInventoryObjects[div+4].name + ".obj", customGUIStyle2);
         if(div+5 < currentInventoryObjects.length)
         GUI.Label(Rect(startPos+2*iconSize+255,startPos+iconSize+60,iconSize+100,90), currentInventoryObjects[div+5].name + ".obj", customGUIStyle2);
     }

What is wrong with this code is that it drastically slows down the frame rate for some reasons. I'm still learning and I don't really use GUI that much, is there any other way to do this?