Salmon Salmon is well known for having one of the highest concentrations of omega-3 fatty acids. However, it’s also an excellent source of B vitamins. A half fillet (178 grams) of cooked salmon can pack 208% of the DV for vitamin B12 . The same serving size may also provide 4,123 mg of omega-3 fatty acids . Alongside its high fat content, salmon offers a high amount of protein, with about 40 grams in a half fillet (178 grams).