Generally speaking, portions should include approximately one quarter to one third of a pound for the main entrée or protein, assuming a starch and vegetable are served as sides. The sides are portioned at approximately four ounces by weight or three-quarters of a cup by volume.
Portion sizes vary considerably based on the type of meal and who and what is to be served. However, in addition to general guidelines, there are a number of everyday objects that can be used as as visual guides for determining portion sizes. It is important to note that these portions are based on an adult's average daily consumption of approximately 2000 to 2200 calories. These portions will vary based on age, body mass index and physical activity levels.
A 4-ounce portion of protein is roughly the size of an average smartphone. Cheese or other fatty foods should be served in portions roughly the shape of an average person's thumb. The volume of a tennis ball roughly corresponds to a good portion size for cut or whole fruits. Cooked rice, vegetables or other starches should occupy about the same volume as a standard incandescent light bulb. Finally, chips or pretzels consumed as a snack should never exceed approximately one ounce, or about two handfuls.