You’ve probably heard that tuna is rich in protein, omega-3 fatty acids, and other beneficial nutrients. It’s no wonder that it’s on the “healthy food” lists recommended by many nutritionists, sports trainers, and even some doctors. It practically has VIP status on supermarket shelves, as it’s extremely practical, long-lasting, and versatile – from salads to sandwiches to pasta. But like any good story, this one has a lesser-known side.
Although canned tuna is considered a healthy choice, not every can is equally innocent. Even “healthy food” can hide pitfalls, especially if we don’t read carefully what we are actually consuming. One key factor that often goes unnoticed is preservation methodWhile tuna in its own juice is generally a safe choice, tuna in oil—especially sunflower oil—can quickly turn from a cardiovascular ally to an enemy. And this is especially important for people who already have high cholesterol.
What's actually in canned tuna – and why does it matter which one you choose?
Tuna is an excellent source in terms of composition high-quality protein – 100 grams of tuna in its own juice contains about 25 grams of protein, which is more than enough for a single meal. It is also energy-moderate – the same amount contains only about 100 calories, making it an ideal food for those who want to lose weight or maintain a healthy body composition. However, the nutritional picture changes drastically when tuna is transferred from water to oil.
Tuna, canned in sunflower oil, contains significantly more fats, including those that increase LDL cholesterol levels – the so-called “bad” cholesterol. Sunflower oil is of plant origin, but it contains significant amounts of omega-6 fatty acids, which in excess can be pro-inflammatory and negatively affect the lipid profile. Although the oil can be drained, quite a lot of fat remains in the fish itself – and these are precisely the hidden calories that sneak into our diet under the guise of a “healthy choice”.
Therefore, experts recommend that people with dyslipidemia, high blood pressure, or cardiovascular disease decide for tuna in its own juice or brineThis type of tuna does not contain added fats, preservatives or other additives that could put an additional burden on the body. If you are going to use tuna in oil, it is better to use it olive oil, which has a positive effect on cardiovascular health due to its content of monounsaturated fatty acids - but moderation is also important here.
Not just protein: tuna as a source of micronutrients
High-quality canned tuna contains many important microelements. It is rich in iodine, which is essential for proper thyroid function and metabolism, and with potassium, which regulates blood pressure and supports muscle function. It also contains phosphorus, important for bone and tooth health, and iron, which participates in the formation of red blood cells and prevents fatigue. In addition, tuna contains B-complex vitamins, such as B3 (niacin), B6 and B12, which are essential for the normal functioning of the nervous system and energy conversion.
Another important feature is the presence omega-3 fatty acids (EPA and DHA), which have anti-inflammatory effects, protect the heart, promote cognitive function and have a positive effect on mood. Ironically, the wrong choice of oil can overshadow these otherwise excellent effects - which means that it is not enough for tuna to contain good fats; it is also important not to add bad ones to it.
How many times a week is it still safe?
Nutritionists unanimously recommend that a healthy adult can safely consume canned tuna. three to four times a week. However, there is an important caveat here: larger types of tuna can contain traces of mercury, so it is advisable for pregnant women, nursing mothers and young children to limit their consumption. Whenever possible, choose tuna from the following types: with lower heavy metal content (such as skipjack or yellowfin tuna), and check sustainable fishing certificates.
Even a “healthy sandwich” can be a diet trap
A quick tuna salad or sandwich often seems like a healthy lunch option, but adding mayonnaise, sugary dressings, or white bread can turn the entire meal into a calorie bomb. Pairing tuna with whole-grain bread, fresh vegetables, and a few drops of lemon juice or olive oil will make your meal balanced, nutritious, and easy on your body and your scale.
Conclusion: Tuna should stay, but the label should be your first concern
Canned tuna is – when chosen correctly – one of the most nutritious and convenient sources of protein you can incorporate into your modern lifestyle. However, choosing tuna in sunflower oil can have a negative impact on your health, especially if you have high cholesterol or other cardiovascular problems. The key is in the details – the fine print on the can.
The next time you reach for a can of tuna, your first thought shouldn't be, "What should I cook?" but, "What does it say on the label?" Because sometimes the difference between a healthy lunch and a nutritional blunder is just a few drops of the wrong oil.
