Tuna is a saltwater fish consumed all over the world and has become one of the most important commercial fishes today. It is enjoyed in many forms whether it is fresh or canned. People enjoy eating it in many ways. Tuna has now become one of the essential food items in our daily lives. Tuna fish is considered a delicacy in most locations where it is exported and cooked. Sushi, Tuna salad, Tuna steak, Tekkadon, and many more cuisines like these are popular choices among fancy restaurants. It contains many essential nutrients with no carbohydrates and much less content of fat. In 2019, it was estimated that the total sales of tuna fish went up to a record-breaking 3.1 million$ US dollars and is still rising.

How long is canned tuna good for?

Canned tuna is most likely to stay good on the shelf for about 3-5 years. Whereas when canned tuna opened, it should be consumed within 1-2 days or else it starts to spoil. But the question arises that can we eat spoiled tuna?


No, we cannot eat spoiled tuna because it can cause many foodborne illnesses such as scombroid food poisoning. Tuna fish naturally have high levels of histidine. When the tuna fish is not properly stored, bacteria attack the fish and start converting histidine into histamine as a result there is a significant increase in the nitrogenous content. Spoiled fishes tend to have high levels of histamine that act against our immune system. After heating or freezing, histamine does not eliminate in the contaminated fish. It is better to throw away the spoiled tuna fish.

The most appropriate strategy to avoid deterioration is to refrigerate or freeze the fish as soon as possible after it has been caught. It will stop the bacteria from growing and hence preserving the fish for a long time.

Following precautions should be taken before the consumption of canned tuna. Always check the best before date written on the can and consume it within that particular date. Check the can for any leakages. If you have found a leaking point on the can, then never consume it because the bacteria may have grown in it and have already spoiled the fish inside.

How to check if Tuna is spoiled?

You can also check if the fish is spoilt or not by smelling the odor. If you experience a foul smell, it is due to the increased nitrogenous content that means the tuna is spoiled. The color of spoilt tuna fish may also get changed to brown, black, or green. The correct color for tuna fish is bright red or pink. After following all of these precautions, you take your first bite and yet still you experience something off, leave the rest and don’t consume it.

Other FAQs about Tuna which you may be interested in.

How much tuna can a cat eat?

Can cats eat tuna every day?

Can canned tuna go bad?

What to do if you eat spoiled Tuna?

If a person ate spoilt tuna, symptoms arise within 20- 40 minutes. These include nausea, headache, dizziness, facial flushing, and fast heartbeat and, may also develop cold-like symptoms. Patients with asthma are more vulnerable to respiratory disorders such as difficulty in breathing or wheezing etc. Some additional symptoms may include rashes on the body, swelling, diarrhea, or abdominal pain. These symptoms may last for 1-2 days. It is better to see a doctor if you are experiencing any of these symptoms. In severe cases, the individual may experience blurred vision or swelling of the tongue. In rare cases, this poisoning may even lead to death.

Treatment for Scombroid poisoning

Treatment for scombroid poisoning includes anti-histamines. Anti-histamines such as diphenhydramine and ranitidine are used together with intravenous fluids to treat mild cases of scombroid poisoning. In worst cases, doctors may also prescribe steroids and epinephrines together. Patients are advised to rest and keep their feet slightly elevated.

So, if you are a big fan of tuna and eat it very often then you should look after the precautions before eating it. Fresh tuna should be consumed within 1-2 hours after fishing. If you have not stored the tuna fish properly then its quality might deteriorate and get spoiled. Never eat a spoiled tuna as it can lead you to several foodborne illnesses which symptoms may include nausea, dizziness, facial flushing and, you might even get rashes, diarrhea, or abdominal cramps. In rare cases, you might even die. So it is better to see a doctor if you are experiencing any of these symptoms after eating tuna. He will then prescribe you some anti-histamines. In worst cases, he might even prescribe you epinephrines and steroids. Most patients usually recover from this poisoning within 3-4 days.

Nowadays, tuna are coming with higher than average mercury content which can also cause severe health effects. Due to increased air and water pollution, toxic contents are found most often in fishes also. It is recommended for pregnant women and children not to consume tuna at all.

So always be careful and keep in mind the proper procedures before eating tuna.