Good for the heart, bad for the nerves and kidneys: The truth about tuna

Whether in a salad or Sushi, the Germans are eating more and more tuna. He scores with a fine taste, low in calories and the highest amount of long-chain Omega-3 fatty acids. Minus points: mercury, moreover, is hardly sustainable fishing. The most important thing about the predator and how healthy he really is.

Tuna is in the Trend: 151.222 tons were consumed in Germany in the year 2017, nearly 40,000 tons more than in the previous year. Tendency for 2018: rising. The current Per capita consumption accounts for almost three kilograms of tuna, as the fish information centre FIZ in Hamburg reports. The majority of them (97 per cent) relates to canned fish and ends up on a salad, Sandwich, Pasta and Pizza. Only a fraction comes as a frozen or fresh goods to the table, prefer to be grilled or in the Form of Sushi.

Tuna fish for Foodies

The popularity is easy to explain: tuna fish, characterized by firm flesh, its taste is fine and almost with the veal meat to compare. Many Gourmets are convinced, prefer therefore, especially the White tuna. As a delicacy, the Red tuna (blue fin or Atlantic tuna), which is especially valued in Japan for Sashimi, and the meat is traded in the Asian market to large sums of money. In Germany, however, yellow comes mostly fin tuna on the table. The main countries of origin are Papua new Guinea, Ecuador, the Philippines and Vietnam.

It is often sold under the name “tuna fish”, however the Real Bonito. This is a closely with tuna and mackerel, related food fish, the tuna is confusingly similar and almost identical tastes.

Tuna fish provides more Omega-3 fatty acids than any other fish

In addition to the delicate taste of tuna convinced, however, primarily due to its ingredients. The most important group of which: Omega-3 fatty acids, the long chain fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA).

These health valuable, long-chain fatty acids EPA and DHA are found exclusively in fish. 100 grams of cooked tuna supply 4.923 milligrams (according to the Federal food key, Version 3.02), in order for tuna to the theme of this special Omega-3 fatty acids frontrunner, ahead of salmon and herring!

So much EPA and DHA per day are important

The total quantity of tuna consists of nearly 2,500 milligrams of docosahexaenoic acid (DHA) and 1620 mg of eicosapentaenoic acid (EPA). “EPA and DHA reduce Triglyceride levels in the blood, confirmed by many studies and reduce the risk for cardiovascular diseases,” reports Silke rest Meyer, diploma in nutritional science expert at the German society for nutrition (DGE).

The most valuable fatty acids improve the flow properties of the blood and prevent atherosclerosis, with its complications high blood pressure, heart attack and stroke. About 250 milligrams of EPA and DHA per day, the by coronary heart disease-related deaths to prevent, – stated in the DGE guideline “fat intake and prevention of selected diet-related diseases”

Because the body Omega-3 can store fatty acids well, it is not necessary a daily morsels of fish to eat, ranging from food scientists to be the recommended one to two servings of fish per week.

Other positive effects of EPA and DHA:

  • To have a favorable influence on inflammatory and immune response
  • Important for growth and development of the brain
  • Improved Muscle Function
  • Indispensable for the growth and function of the brain

In addition, tuna fish fat provides-soluble vitamins such as A, D and E and the B vitamins, also a lot of potassium and little sodium, what is high blood pressure useful. The trace elements Iodine and selenium round out the profile of the tuna.

As an important aspect of high-quality Protein which saturates well. 100 grams of tuna consists of almost a quarter from protein, however, it provides only 110 calories. Tuna fillet is therefore good for losing weight.

Tuna out of a can, or better as a frozen or fresh product?

The decision to choose canned or frozen or fresh goods, is particularly important for the calories a role:

  • 100 grams of canned tuna in Oil supply 190 calories,
  • Can of tuna in its own juice 160,
  • Fresh tuna steak, or frozen 110.

In total, goods, or TK, however, is fresh-tuna under the health aspect is hardly better than tuna out of the can. “The Omega-3 fatty acids, but also Iodine and fat-soluble vitamins will remain intact, also preserved in a box,” explains the nutritionist.

Basically, canned tuna is also in relation to two other aspects of the perhaps better Alternative to TK, or fresh tuna:

1. Canned tuna is much cheaper than fresh or frozen Steaks

2. In the case of sustainability and environmental impact can of tuna cuts much better. “During the long transport routes, TK and fresh goods energy consuming cooled, which leads to a high CO-emissions,” criticized Silke rest Meyer. The falls at tin fish away, he must not be cooled.

Poison in tuna fish – more and more mercury

But in addition to the many healthy properties, on the tuna fillets have: In the past, significant residues in the sought-after fish have been in part discovered, especially mercury. One study, for example, the Foundation shows, that none of the samples was free of pollutants. Has been tested can of tuna and frozen goods.

Organic mercury compounds like methyl mercury can kidney when there is a permanent strain, and nerve damage. Also, the connection is considered to be particularly dangerous because they can cross the blood-brain barrier and across the placenta to the fetus reached. How the mercury gets into the fish, is still largely unknown. It is established that the mercury content in the sea water triple since the industrial Revolution tripled, and the mercury contamination of edible fish such as the yellowfin tuna since the end of the 90s, a demonstrably on the rise.

The EU has therefore set a limit of one milligram per kilogram of tuna. The Test quantities were all far below the EU limit value.

So much tuna you may eat

What does this mean for the consumer – General all-clear for tuna and how often can I eat tuna, I was taking a risk? “Tuna fish, sword fish, pike, halibut and cod can be loaded with methyl mercury,” confirms Silke rest Meyer. Of total fish waiver, she does not consider, however: “In the case of a fish eating a week one to two servings of the health benefits outweigh the negative effects of a possible pollution with mercury and other pollutants. However, women in pregnancy and lactation should restrict consumption of these fish species.“

This Council is also the Federal Institute for risk assessment (BfR) and the European food safety authority (EFSA) in a recent review of methyl mercury in food.

In addition, it is assumed that tuna, like many other species of fish also, more and more micro-plastic. For example, a recent study has revealed that over 70 percent of the fish, which serve, among other things, the predatory species of tuna as a food, are contaminated with micro-plastics. Whether and the extent to which micro-plastics in the body is detrimental to the people, is not yet conclusively investigated – a soothing idea, it is not, however, the plastic with the food.

Tuna should be environmentally friendly

In addition to this criticism, only Greenpeace and the WWF, not to find fault, in addition, tuna consumption in General. Because longline and trawl fishing, the most commonly used types of Fishing for tuna, will lead to massive “bycatch”. Other fish such as dolphins, but also sea turtles and birds die in cruel. Many fishing areas are overfished in addition, the Red list of world conservation Union IUCN lists this species of Tuna:

  • Blue tuna
  • Yellow fin tuna
  • Bigeye tuna
  • White Tuna

With Mäst and breeding facilities have been trying, therefore, to multiply the precious fish. However, this is difficult, the fish are extremely sensitive to their eggs, only a tiny fraction survived. In addition, these predatory fish are aggressive, they would even eat each other in the cage systems. In Japan, biologists, therefore, try mackerel fishing with the tuna are closely related, to use as a Leiheltern and to increase the fish yield. But still the process is too time-consuming and expensive.

Tuna fish and seal with a clear Conscience, tuna enjoy

Nevertheless, it is possible to buy tuna without the environmental or animal welfare relevant concerns. Fish seal of approval to ensure that fishing or aquaculture to follow the principles of sustainability, Overfishing, to fishing methods and, if possible, no by-catch. “About the MSC – and ASC-seal,” says the nutrition expert. ASC is the Aquaculture Stewardship Council, MSC Marine Stewardship Council. In addition, the “SAFE guarantee”seal on fishing methods that endanger dolphins. In addition, some fish producers to make additional disclosures about the method of fishing.

Conclusion: Who when buying for a seal of approval and tuna species respects, behave ecologically correctly, and can the tuna fish without a guilty Conscience enjoy. No other fish offers such a large amount of valuable, special long-chain Omega-3 fatty acids such as DHA as well as EPA and even the life may extend.