Melody, 
Moderation really depends on the food you are referencing. Most foods that are listed as “in moderation,” mean that if you are not cautious, you will go over your macros. Nuts, for example, are great sources of fat, but contain higher amounts of carbs than other foods.Because a cup of sliced almonds contains 8g of carbs, if I am to eat almonds, I need to make sure that I measure them before hand, and don’t eat them freely. 
Basically, use “in moderation” to mean small portions and be cautious. Don’t free eat any food that you are told to have in moderation. Also, be sure to check the nutritional information to make sure that the calories and macros fit into your day, and are worth it!