have been identified in advisories as fish that pregnant women should not consume. In the Gulf of Mexico, the regional fishery management plans allocate 68 percent of the king mackerel harvest to recreational fishermen (GMFMC, 2006).
Table 2-6 shows that several popular species are overfished and supplies are declining. Among capture fisheries worldwide, 28 percent of fish stocks have been estimated to be depleted or overexploited (FAO, 2002). In the United States, over 18 percent of the 236 fish stocks or stock complexes with known overfishing status have a mortality rate that exceeds the overfishing threshold (i.e., subject to overfishing) (NMFS, 2005b). Supply predictions for shark (Baum et al., 2003), tilefish, king mackerel, and swordfish (identified in the joint FDA/US EPA methylmercury advisory) suggest that they will likely decrease. In addition, changes in the supply of other wild-caught seafood will also influence seafood selections for all segments of the population in the future.
Foods with similar nutrient profiles are often grouped together for the purpose of making dietary recommendations. Seafood is grouped with meats, poultry, eggs, nuts, legumes, and seeds as major contributors (supplying >50 percent) of protein, niacin, zinc, and vitamin B6 to the diet. These foods are also substantial contributors (supplying >10 percent) of vitamins E and B12, thiamin, riboflavin, phosphorus, magnesium, iron, copper, potassium, and linoleic acid. Among these foods, however, higher levels of selenium and the omega-3 fatty acids EPA and DHA and generally lower levels of saturated fats are unique to seafood. Although EPA and DHA are found in other protein-rich foods (i.e., poultry and eggs), fish that are high in EPA/DHA (e.g., salmon, lake trout, and white [albacore] tuna) have the highest concentration per serving among food sources. Table 2-7 provides a comparison of the availability of some macro- and micronutrients, including the omega-3 fatty acids EPA (20:5 n-3) and DHA (22:6 n-3) in three types of seafood, as well as chicken, beef, and eggs, and the alpha-linolenic acid (ALA; 18:3 n-3) in walnuts.
An important reason for choosing seafood over other protein food sources is that it is a primary source of the omega-3 fatty acids EPA and DHA. The benefits of these two fatty acids are described in detail in Chapter 3. The following discussion provides information about sources and consumption patterns of EPA/DHA.