Fish is a lean protein, so it belongs in the protein group. The Centers for Disease Control and Prevention recommends that each person eat at least 8 ounces of fish per week.
Other proteins in this group include nuts, beans and eggs, as well as other types of meat like beef, poultry and pork. An average woman needs 46 grams of protein per day, while an average man needs 56 grams per day. By contrast, 3 ounces of meat, which is about the size of a deck of cards, contains approximately 21 grams of protein. The other primary food groups are dairy, grains, fruits and vegetables.