Canned tuna is a highly beneficial food for humans. It is shelf-stable, nutritionally valuable, and a great addition to many recipes. Since the average price of a can is from 50 cents to $3, it is also an affordable grocery.
However, you can often find articles questioning the safety of consuming this food because of mercury content. On the other hand, US dietary guidelines recommend eating tuna twice a week. Let’s see where the truth is and is canned tuna healthy for you and your family.
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Types and Sources of Tuna
Tuna canning began about 120 years ago, and almost immediately, this seafood product became one of the most popular in the US. Believe it or not, this country imports over 300 million pounds (136 million kilograms) of canned tuna each year from Indonesia, Thailand, Ecuador, the Philippines, and Vietnam. The most wanted commercial tuna species include:
Albacore tuna
- It is so-called white tuna meat caught primarily in the Pacific Ocean
- This type of tuna grows to 80 pounds (36 kg) and lives approximately 12 years in the open ocean
- In the US, you can find it as loins or fresh-packed canned tuna
Skipjack tuna
- This species is labeled as light tuna comes from the Pacific Ocean
- It grows up to 70 pounds (31.7 kg) and reaches a length of 4 feet (1.2 m)
- The US import fresh, frozen, and canned tuna from Mexico, Ecuador, and South Korea
Yellowfin tuna
- You can find fresh loins and steaks, as well as frozen tuna steaks all over the US
- It is rarely canned as light tuna meat
- This tuna, which comes from the Atlantic, Pacific, and Indian Oceans, can grow up to 400 pounds (181 kg) and lives about seven years
Bigeye tuna
- This tuna lives about eight years in the Atlantic Ocean and can grow to 6.5 feet (2 m) long
- You can find it as a part of sushi dishes or buy fresh or frozen loins and steaks
Bluefin tuna
- This tuna lives in the Atlantic Ocean up to 20 years and can reach 1,500 pounds (680 kg) in weight
- It can produce approximately 10 million eggs each year
- It is a part of sushi dishes exclusively
The canned tuna sold in the US supermarkets is often albacore, but you can find a mixture of yellowfin and skipjack tuna, as well. The most popular canned tuna in the US is inexpensive, so-called light tuna that contains skipjack with the addition of yellowfin.
Canned Tuna Nutrition Facts
Canned tuna contains the most necessary nutrients necessary for a healthy human diet. However, its nutritional value will vary depending on the brand used.
On average, each water-packed can of light tuna without salt that weighs 2 ounces (57 g) contains:
Water-packed tuna nutrition for a can of 2 ounces (57 g) |
|
|
Calories |
49 |
| Protein |
11 g |
|
Total fat |
0.5 g |
| Sodium |
140 mg |
|
Saturated fat |
0 g |
| Carbohydrates |
0 g |
|
Fiber |
0 g |
Keep in mind that oil-packed tuna can of the same weight contains twice as many calories per unit.
Oil-packed tuna nutrition for a can of 2 ounces (57 g) |
|
|
Calories |
112 |
| Protein |
17 g |
|
Total fat |
5 g |
| Saturated fat |
1 g |
|
Sodium |
236 mg |
| Iodine |
17 µg |
|
Carbohydrates |
0 g |
| Fiber |
0 g |
Regardless of the manufacturer, each can of tuna contains the following nutrients:
Protein
Each can of tuna contains 1.5 ounces (42 g) of high-quality protein, including all of the essential amino acids.
Fats
Tuna is low in overall fat, but it contains a high amount of healthy unsaturated omega-3 fatty acids. Each can of light tuna offers only 0.05 ounces (1.4 g) of fat, but varieties such as canned bluefin and white albacore tuna are more fatty options.
Omega-3 fatty acids are crucial for keeping your brain healthy and can help people suffering from depression. They reduce inflammation in the human body and decrease the level of cholesterol. Plus, they reduce the risk of heart disease, arthritis, and even cancer.
Vitamins and minerals
Canned tuna contains necessary minerals, including calcium, phosphorus, iron, zinc, potassium, sodium, magnesium, and selenium. Also, it is rich in vitamin A, B-vitamins, and choline.
- Vitamin B3 – A half of a canned light tuna contains 11.3 mg of niacin. Since a daily need for this vitamin in women is 14 mg and for men 16 mg, you can understand how beneficial this food can be for your health. Regular intake of this vitamin will keep your nerves, digestive system, and skin in excellent condition.
- Vitamin B12 – The average person needs to intake 2.4 µg of this vitamin a day. Since half of the canned light tuna contains 2.5 µg of vitamin B12, this meal will supply all your daily needs. It will be enough to support brain function and regular blood cell production.
Carbs and fiber
Canned tuna doesn’t contain either fiber or carbohydrates, so it is recommended to anyone who takes care of the weight or has a diabetes problem.
Health Benefits of Canned Tuna
Both fresh and canned tuna provide a lot of health benefits, including:
1. Prevent anemia
Since tuna contains iron, folate, and vitamin B12, it can prevent anemia in people whose diet is deficient in these micronutrients.
2. Promote heart health
Tuna is a rich source of two omega-3 essential fatty acids, including EPA and DHA. Thanks to that, it lowers triglycerides, keeps your heart healthy, and reduces the risk of cardiovascular disease.
3. Support the control of blood sugar
Since canned tuna doesn’t contain carbohydrates, it is an excellent solution for people who have diabetes. The American Diabetes Association included albacore tuna in the list with top-ten superfoods for people with this condition.
4. Support muscle mass retention
Tuna contains a high amount of polyunsaturated fat that increases lean body mass in seniors. Plus, essential amino acids allow better synthesis of muscle protein, which supports muscle mass retention during the aging process.
5. Decrease the risk of dementia
A balanced intake of omega-6 and omega-3 fatty acids from tuna will slow the progressive development of dementia in patients after a stroke or brain injuries. By regular intake of this seafood, you will boost your memory and cognitive function.
Adverse Effects of Canned Tuna
1. Allergies
Fish is a well-known allergen, which can cause anaphylaxis. The problem is that you can confuse the symptoms of an allergy with scombroid food poisoning. This condition occurs after consuming spoiled fish, including tuna, high in histamine.
You can expect the first symptoms of histamine poisoning after five minutes or a couple of hours after the ingestion. They include tongue swelling, wheezing, faintness, diarrhea, and nausea. An allergist can determine if the problem occurs as a result of an allergy or poisoning.
2. Mercury
The level of mercury in different tuna species can vary, determining their safety level. For example, the level of this mineral in albacore tuna is three times higher than in the skipjack one.
Level of mercury in different tuna species |
||
| Tuna species | Mercury per 3 ounces (85 g) | |
| Canned light tuna | 10.7 µg | 0.13 ppm |
| Canned albacore tuna | 29.7 µg | 0.35 ppm |
| Fresh or frozen albacore tuna | 30.4 µg | 0.36 ppm |
| Fresh or frozen skipjack tuna | 12.2 µg | 0.14 ppm |
| Fresh or frozen bigeye tuna | 58.6 µg | 0.69 ppm |
| Fresh or frozen yellowfin tuna | 30 µg | 0.35 ppm |
Mercury is a dangerous mineral, which accumulates in the human body, causes damage to the nervous system, and consequently result in impaired memory and fine motor skills. It is particularly dangerous for unborn babies and toddlers.
How Much Tuna is OK?
All canned white tuna you can buy in the US is albacore, while the most canned light products contain skipjack tuna. The mercury level in these fish is different, and you should be careful when consuming this type of food.
Max allowed mercury doses based on different body weights |
||
| Bodyweight | Dose per day | Dose per week |
| 100 pounds (45,3 kg) | 4.5 µg | 32 µg |
| 125 pounds (56.7 kg) | 6 µg | 40 µg |
| 150 pounds (68 kg) | 7 µg | 48 µg |
| 175 pounds (79.4 kg) | 8 µg | 56 µg |
| 200 pounds (9.7 kg) | 9 µg | 64 µg |
The recommended amount of albacore:
- Adults – They can eat this species up to three times a month. The recommended portion for women is a can of 6 ounces (170 g), while men can consume a portion of 8 ounces (227 g).
- Children from 6 to 12 – They can safely consume two portions of 4.5 ounces (127.5 g) a month.
- Children under six – Toddlers shouldn’t eat more than one portion of 3 ounces (85 g) a month.
The recommended amount of light tuna:
- Older children and adults – It is safe to consume this tuna once a week.
- Children under six – Recommended portions of 3 ounces (85 g) include not more than three meals per month.
- Pregnant or nursing women – These women should avoid bigeye tuna entirely, but they can eat other kinds of this fish in moderation.
Summary
Canned tuna is an excellent source of essential nutrients when consumed in moderation. However, avoid eating this food in excess to prevent damage to the nervous system and possible heart diseases.