The intake of tuna is favourable for a balanced diet due to its high protein, iron and niacin content.3 As a general rule, the amount of calories is higher in tuna packaged with oils than those that have been packaged “natural” (100 grams of canned tuna contain 285 calories, while the same amount of fresh tuna contains 200 calories).3 In some countries such as Spain, it is common to see cans of canned tuna in pickled form. Some authors mention that despite the high omega-3 content of tuna, most of it is lost during processing and packaging.4 The most common ingredients are salt, monosodium glutamate, hydrolysed protein. Spices, garlic, herbs, etc. are sometimes added. Sometimes it is acidified with lemon juice.
Excessive consumption of canned tuna is not advisable due to its purine content (which the body converts into uric acid). This intake is not recommended for people suffering from hyperuricaemia or gout. The salt content has been of concern to certain sectors of the population with “high blood pressure”, which is why low-salt variants have been marketed since the beginning of the 21st century. The cholesterol content is not low (50 mg/100 g), but is not higher than in other products of animal origin. However, the presence of fatty acids reduces its incidence.