Manufacturers often pack tuna in either water or sunflower oil. While it may add more calories and fat to the tuna, sunflower oil contains healthy unsaturated fats and Omega-3 fatty acids, which may be worth the additional calories.

A 2.6 oz. serving of tuna packed in sunflower oil contains 160 calories, including 90 calories from fat, according to Fat Secret.

The same 2.6 oz. serving of tuna packed in sunflower oil also provides 10 g of fat, 1 g of saturated fat, 6 g of polyunsaturated fat, 2.5 g of monounsaturated fat, 35 mg of cholesterol, 290 mg of sodium, 200 mg of potassium, 1 g of carbohydrates, 0.5 g of dietary fiber and 18 g of protein, notes Fat Secret.

The unsaturated fats contained in tuna packed in sunflower oil may help lower cholesterol and reduce the risk of heart disease, according to the Mayo Clinic.