Fresh tuna has significantly more potassium than either of its canned counterparts with 124 milligrams, while canned tuna in water and oil both have potassium in the 50-59 milligram range.

Find out what nutrients are in tuna and learn how it can help you lower your risk of heart disease, cancer, ... A 4-ounce serving of white tuna contains: Calories: 145; Protein: 26.77 grams; Fat ...

This high protein content plus its low number of calories - a five-ounce can of skipjack tuna contains only 80 calories - makes the fish "an ideal food for weight management," says Messer.

Calories in an egg: 65 calories. Calories in can of tuna (in springwater): 82 calories per small can. Check out our detailed protein calories chart for more. Ultimate calorie guide.