Cod is a very lean white fish, but nutrition tables can look contradictory because “cod” may mean fresh fish, dried salted fish, or cod that has already been soaked and cooked. Those forms cannot be compared per 100 g as if they contained the same amount of water.
Changes in water explain much of the apparent contradiction. Drying and salting pack more fish solids and salt into each 100 grams; soaking adds water back while allowing sodium to move out.
Fresh cod: high protein, very little fat
A USDA reference for raw Atlantic cod provides about 82 calories, 17.8 g protein and 0.7 g fat per 100 g. It also contains about 54 mg sodium and 413 mg potassium.
Cooking removes water, concentrating protein by weight. Depending on method and doneness, cooked cod commonly lands around 20–23 g protein and roughly 90–105 calories per 100 g, with less than 1 g fat if no oil is added. A cooked serving can therefore provide substantial protein without much energy from the fish itself.
Salt cod is a different product by weight
During curing, cod loses substantial water and gains a large amount of salt. A dried salted cod reference reaches roughly 290 calories, 62.8 g protein and 7,027 mg sodium per 100 g.
That does not mean a prepared serving delivers three times as much protein as fresh cod. Drying removes water, so 100 g of the cured product contains far more fish solids. During desalting, the fish absorbs water again and sodium diffuses out. Comparing dry salt cod with fresh fish gram for gram is therefore a comparison between very different hydration states.
Desalting can dramatically reduce sodium
One food-composition reference for desalted, cooked cod lists about 84 calories, 20.4 g protein, 0.25 g fat and 134 mg sodium per 100 g. That is dramatically lower sodium than the dried salted starting reference.
The final value depends on piece thickness, soak time, temperature, water changes, and starting salt concentration, so there is no single universal sodium number for “desalted cod.” A piece that still tastes very salty may retain considerably more sodium than one soaked longer with several water changes.
How long does salt cod need soaking?
Thick loins generally require more time than small flakes. Home cooks commonly soak it under refrigeration and replace the water several times. The purpose is to create a concentration gradient that lets sodium diffuse out of the fish over time.
Keep the soaking fish cold. Leaving it at room temperature for many hours to speed the process is not a food-safety improvement. Use enough water to surround the pieces well and keep them submerged.
Cod remains a lean fish
At roughly 0.7 g fat per 100 g raw, cod is far leaner than salmon, which commonly provides around 10–13 g fat per 100 g depending on species and origin. That difference changes both calories and fatty-acid profile.
Adding 15 g cooking oil contributes about 135 calories—far more energy than the cod’s own fat. Breaded, fried, confited, or cream-sauced cod can therefore become a much more energy-dense dish even though the fish itself is extremely lean.
Is cod a good protein source?
Yes. A 150 g cooked serving at about 21–22 g protein per 100 g provides roughly 31–33 g protein. That easily functions as the main protein source in a meal.
With cured cod, the main nutrition variable to watch is not protein but how much sodium remains after desalting. For someone limiting sodium, the product form and soaking process matter much more than the impressive protein number on a dried-food table.
Fresh and salted cod also cook differently
Fresh cod contains more water and has a delicate flaky texture. Salt curing changes the muscle structure; after soaking, salt cod retains a firmer texture and characteristic flavor that many traditional recipes depend on.
That means the two forms are not always interchangeable by weight. A recipe written for soaked salt cod may rely on its texture and residual seasoning, while fresh cod may need different salting and handling.
Bottom line
Fresh cod is lean and protein-rich; salt cod concentrates protein and especially sodium because water has been removed. Always check whether a nutrition value refers to fresh, dried salted, or desalted cod.
If sodium is the main concern, do not use the fresh-fish number to estimate a dish made with cured cod. Soaking can reduce sodium enormously, but the final amount depends on the actual desalting process.
Sources
- USDA FoodData Central — Atlantic cod, raw — Reference composition for raw Atlantic cod per 100 g.
- USDA FoodData Central — Cod, dried and salted — Reference illustrating the concentration of protein and sodium after drying and salting.
- TBCA — Cod, salted, desalted, cooked — Analytical example of desalted cooked cod with far lower sodium than the dried salted product.