Eating more than two tins of tuna a week can increase your intake of methylmercury, a neurotoxin that builds up in your body, potentially causing neurological issues like memory problems, tremors, vision/hearing loss, irritability, or numbness, especially with high, long-term consumption; while tuna offers nutrients, moderation is key, with health guidelines suggesting varying fish types and limiting higher-mercury options, particularly for sensitive groups like children, pregnant women, or those with existing conditions.
You would have to eat around 25 tins (at 95g a tin) of it a week before you hit the maximum tolerable intake of mercury. For pregnant people (or people trying to get pregnant), the limit would be around 12 tins (at 95g a tin) a week. It is unlikely many consumers will reach these limits.
However, according to the NHS, which states a healthy, balanced diet should include at least two portions of fish a week, there's nothing there to say you can't eat tuna every day, unless you're trying for a baby, or pregnant.
However, overconsumption of fish with high levels of organic mercury, such as tuna, can cause methylmercury poisoning and a variety of abnormal central nervous system-related symptoms such as paresthesia, ataxia, hearing impairment, and progressive constriction of the visual fields12-15).
First things first, canned tuna is packed with lean protein. Protein helps repair and build tissues, supports muscle growth, and keeps you feeling satisfied and full. So if you're aiming to build muscle, lose or maintain weight, or simply maintain a healthy body, canned or pouch tuna is a superb option.
Initial signs and symptoms, such as fever, chills, shortness of breath, metallic taste, and pleuritic chest pain, may be confused with metal-fume fever, which is caused by cadmium exposure. Other possible symptoms include stomatitis, lethargy, confusion, and vomiting.
The most common symptoms are rash, diarrhea, reddening or flushing of the face and sometimes the neck, arms, and upper part of the body, sweating, headache, and vomiting. Burning sensation or swelling of the mouth, difficulty swallowing, stomach pain, and heart palpitations may also occur.
Some tuna cans that say do not drain because they don't add oil, water, fillers, preservatives, and GMO soy broth. Cans that say do not drain contain only tuna or sometimes salmon. They only have natural occurring fish oils and juices and those are rich in omega threes.
It is safe for everyone (including pregnant women) to consume canned tuna as part of their fish intake. Canned tuna generally has lower levels of mercury than tuna fillets because smaller tuna species are used and the tuna are generally younger when caught.
Histamine Toxicity (Scombroid Fish Poisoning)
Scombroid fish poisoning, also known as histamine toxicity, occurs when bacteria in improperly stored tuna produce large amounts of histamines. Even people without a tuna allergy can experience symptoms similar to an allergic reaction if they eat contaminated fish.
To limit mercury intake from tuna, here are the guidelines: Best choice: Eat 2 to 3 servings per week of canned light skipjack tuna. Good choice: Eat 1 serving per week of yellowfin tuna or white albacore tuna. Choice to avoid: Don't eat bigeye tuna.
According to the FDA, canned light tuna, made primarily from skipjack, is recognized as a low-mercury fish and is designated a "best choice." The FDA recommends eating 2 to 3 servings a week, or about 8 to 12 ounces.
To get rid of food poisoning fastest, focus on hydration with water, broth, or oral rehydration solutions, get plenty of rest, and avoid dairy, caffeine, spicy, and fatty foods; most cases resolve in a couple of days, but if symptoms are severe or persist, see a doctor. The key is supportive care to prevent dehydration and let your body fight the infection, as antibiotics aren't usually needed.
Symptoms generally appear within minutes to an hour after eating affected fish. They typically last 3 hours, but can last several days.
Other mercury removal options include home remedies such as eating a nutrient- and vitamin-rich diet, increasing fibre intake, and drinking more water to flush out mercury from the body.
Symptoms of poisoning can include:
Subsequently, mercury ions accumulates in the brain and kidney and causes multiple organ damage in the renal, nervous, cardiovascular, and musculoskeletal systems. 6, 7, 8 Because of the strong affinity of mercury for the kidney tissue, the kidney is one of the most susceptible organs to mercury poisoning.
Tuna is low in calories and nutrient-dense, making it an excellent choice for maintaining a calorie deficit. Its protein and omega-3 content can help reduce cravings, support fat burning, and promote overall weight loss, though spot reduction of belly fat isn't possible.
Canned light tuna is considered low mercury and safe to eat 12oz a week, with albacore being the exception. Check the oz on the canned tuna. If it's 4-5 oz can, that's 3 cans a week. Other low mercury fish: salmon, shrimp, pollock, and catfish.
Tuna is a relatively low-calorie and low-fat source of protein, vitamins, and minerals. This makes it a good choice for overall health or for anyone with a goal of weight loss or weight management.
Buy skipjack and yellowfin tunas labeled pole-caught, pole-and-line, troll-caught, or FAD-free from the Atlantic or Pacific. Avoid all bluefin tuna, except if you confirm it's Pacific bluefin tuna from a yellow-rated source (scroll down for more information). Avoid tuna caught in the Indian Ocean.
Safe Catch Elite Tuna, simply the lowest mercury tuna of any brand.