The cod you buy may come from the Atlantic Ocean or the Pacific Ocean. Both types are similar enough that one can replace the other, but Pacific cod provide larger, thicker fillets. Cod is a good source of heart-healthy omega-3 fatty acids and is especially rich in lean protein and vitamin B-12. On the downside, some types of cod contain high amounts of sodium, and it’s a moderate source of mercury.
Fish Oil for Your Heart
The American Heart Association recommends eating fish twice a week for its omega-3 fatty acids. These essential fatty acids -- eicosapentaenoic acid, or EPA, and docosahexaenoic acid, or DHA -- are found in fish oil. EPA and DHA lower levels of cholesterol and triglycerides in your bloodstream, according to Colorado State University. Fatty fish such as salmon and tuna have significantly more omega-3, but cod still makes a good choice. A 3-ounce serving of Pacific cod has 0.14 grams of combined EPA and DHA, which is 13 percent of women’s and 9 percent of men’s recommended daily intake.
Rich Source of Lean Protein
Cod gives you a good option for lean protein. A 3-ounce serving of Pacific cod is low in total fat and only has 72 calories. This portion supplies 15.9 grams of quality protein, which gives women 35 percent of their recommended daily allowance. Men need more protein, so they get 28 percent of their RDA. If absolutely necessary, your body can convert protein into energy, but it prefers to use it to fill other life-sustaining jobs, such as building and maintaining muscles, skin, bones, enzymes and hormones.
Vitamin B-12 for Normal Nerves
Vitamin B-12 helps turn the macronutrients you eat into energy, and it’s vital for keeping nerves working properly. It may contribute to a healthy cardiovascular system because it lowers levels of homocysteine in your bloodstream. Homocysteine is an amino acid used to make other essential substances, but when the amount in your blood gets high, it can damage your arteries and increase the risk of blood clots, according to FamilyDoctor.org. You only need 2.4 micrograms of vitamin B-12 in your daily diet. Three ounces of Pacific cod contain 1.96 micrograms, or 82 percent of your RDA.
Variable Sodium Warning
Cod is sometimes treated with a salt solution. Any type of cod may be treated, but it’s often used when the fish is frozen because the salt solution prevents excessive moisture loss when it's thawed. Untreated Pacific cod has about 77 milligrams of sodium in a 3-ounce serving. When it’s treated, the same portion has 316 milligrams of sodium. The two amounts represent the difference between 5 percent and 21 percent of your recommended daily intake of sodium. Check the label on the cod you buy to be sure you don’t consume too much sodium.
Beware Moderate Mercury
The Natural Resources Defense Council rates cod as a moderate source of mercury. Because mercury interferes with neurological development, young children, women who are pregnant or may become pregnant and women who are nursing must be careful about the amount of mercury they consume. They should limit the amount of cod they eat to no more than six servings a month.